@article{tang_vargo_ahmad_jiang_varadinova_dovih_kim_bourguignon_booth_schal_et al._2024, title={Solving the 250-year- old mystery of the origin and global spread of the German cockroach, Blattella germanica}, volume={121}, ISSN={["1091-6490"]}, url={https://doi.org/10.1073/pnas.2401185121}, DOI={10.1073/pnas.2401185121}, abstractNote={The origin of the German cockroach,}, number={22}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Tang, Qian and Vargo, Edward L. and Ahmad, Intan and Jiang, Hong and Varadinova, Zuzana Kotykova and Dovih, Pilot and Kim, Dongmin and Bourguignon, Thomas and Booth, Warren and Schal, Coby and et al.}, year={2024}, month={May} }
 @article{travanty_vargo_schal_apperson_ponnusamy_2022, title={Bacterial Isolates Derived from Nest Soil Affect the Attraction and Digging Behavior of Workers of the Red Imported Fire Ant, Solenopsis invicta Buren}, volume={13}, ISSN={["2075-4450"]}, url={https://doi.org/10.3390/insects13050444}, DOI={10.3390/insects13050444}, abstractNote={Populations of monogyne and polygyne red imported fire ants (RIFA), Solenopsis invicta Buren, are distributed throughout the southern United States. This ant species is hazardous to farm animals and workers, damages infrastructure, and depletes native arthropod populations. Colony expansion is affected by several biotic factors, but the effects of soil microbes on ant behavior related to soil excavation within nest sites have not been investigated. Consequently, we cultured bacteria from RIFA nest soils. The effects of individual bacterial isolates and bacterial cell densities on the choice of digging site as well as digging activity of monogyne and polygyne RIFA worker ants were evaluated in two-choice bioassays. Based on phylogenetic analysis, 17 isolates were selected and tested initially at 5 × 108 cells/mL and 20 workers per assay. Firmicutes (Bacillus, Paenibacillus, Brevibacillus) repelled the ants, but Arthrobacter woluwensis strongly attracted ants. Subsequently, the six isolates having the greatest positive or negative effects on ant behavior were evaluated at a lower bacterial cell and worker ant densities. Ant responses to these bacteria generally decreased as cell densities declined to 5 × 106 cells/mL. Observations of ant behavior during a three-hour, two-choice bioassay revealed that ants generally visited both control and bacteria-treated sand prior to making a digging site choice. Our research results indicate that soil bacteria may mediate ant nest expansion or relocation and foraging tunnel construction. Identification of bacterial metabolites that affect RIFA digging behavior merits additional research because these compounds may provide a basis for novel management strategies that repel RIFA away from sensitive infrastructure or attract fire ants to insecticidal baits.}, number={5}, journal={INSECTS}, publisher={MDPI AG}, author={Travanty, Nicholas V and Vargo, Edward L. and Schal, Coby and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2022}, month={May} }
 @article{lewis_levine_schal_vargo_booth_2022, title={Decade long upsurge in mutations associated with pyrethroid resistance in bed bug populations in the USA}, volume={4}, ISSN={["1612-4766"]}, url={https://doi.org/10.1007/s10340-022-01505-4}, DOI={10.1007/s10340-022-01505-4}, journal={JOURNAL OF PEST SCIENCE}, author={Lewis, Cari D. and Levine, Brenna A. and Schal, Coby and Vargo, Edward L. and Booth, Warren}, year={2022}, month={Apr} }
 @article{travanty_vargo_apperson_ponnusamy_2021, title={Colonization by the Red Imported Fire Ant, Solenopsis invicta, Modifies Soil Bacterial Communities}, volume={8}, ISSN={["1432-184X"]}, url={https://doi.org/10.1007/s00248-021-01826-4}, DOI={10.1007/s00248-021-01826-4}, abstractNote={The long-standing association between insects and microorganisms has been especially crucial to the evolutionary and ecological success of social insect groups. Notably, research on the interaction of the two social forms (monogyne and polygyne) of the red imported fire ant (RIFA), Solenopsis invicta Buren, with microbes in its soil habitat is presently limited. In this study, we characterized bacterial microbiomes associated with RIFA nest soils and native (RIFA-negative) soils to better understand the effects of colonization of RIFA on soil microbial communities. Bacterial community fingerprints of 16S rRNA amplicons using denaturing gradient gel electrophoresis revealed significant differences in the structure of the bacterial communities between RIFA-positive and RIFA-negative soils at 0 and 10 cm depths. Illumina sequencing of 16S rRNA amplicons provided fine-scale analysis to test for effects of RIFA colonization, RIFA social form, and soil depth on the composition of the bacterial microbiomes of the soil and RIFA workers. Our results showed the bacterial community structure of RIFA-colonized soils to be significantly different from native soil communities and to evidence elevated abundances of several taxa, including Actinobacteria. Colony social form was not found to be a significant factor in nest or RIFA worker microbiome compositions. RIFA workers and nest soils were determined to have markedly different bacterial communities, with RIFA worker microbiomes being characterized by high abundances of a Bartonella-like endosymbiont and Entomoplasmataceae. Cloning and sequencing of the 16S rRNA gene revealed the Bartonella sp. to be a novel bacterium.}, journal={MICROBIAL ECOLOGY}, publisher={Springer Science and Business Media LLC}, author={Travanty, Nicholas V. and Vargo, Edward L. and Apperson, Charles S. and Ponnusamy, Loganathan}, year={2021}, month={Aug} }
 @article{funaro_schal_vargo_2019, title={Queen and king recognition in the subterranean termite, Reticulitermes flavipes: Evidence for royal recognition pheromones}, volume={14}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0209810}, DOI={10.1371/journal.pone.0209810}, abstractNote={Royal recognition is a central feature of insect societies, allowing them to maintain the reproductive division of labor and regulate colony demography. Queen recognition has been broadly demonstrated and queen recognition pheromones have been identified in social hymenopterans, and in one termite species. Here we describe behaviors that are elicited in workers and soldiers by neotenic queens and kings of the subterranean termite, Reticulitermes flavipes, and demonstrate the chemical basis for the behavior. Workers and soldiers readily perform a lateral or longitudinal shaking behavior upon antennal contact with queens and kings. When royal cuticular chemicals are transferred to live workers or inert glass dummies, they elicit antennation and shaking in a dose-dependent manner. The striking response to reproductives and their cuticular extracts suggests that royal-specific cuticular compounds act as recognition pheromones and that shaking behavior is a clear and measurable queen and king recognition response in this termite species.}, number={5}, journal={PLOS ONE}, publisher={Public Library of Science (PLoS)}, author={Funaro, Colin F. and Schal, Coby and Vargo, Edward L.}, editor={Nascimento, Fabio S.Editor}, year={2019}, month={May}, pages={e0209810} }
 @article{eyer_matsuura_vargo_kobayashi_yashiro_suehiro_himuro_yokoi_guenard_dunn_et al._2018, title={Inbreeding tolerance as a pre-adapted trait for invasion success in the invasive ant Brachyponera chinensis}, volume={27}, ISSN={["1365-294X"]}, DOI={10.1111/mec.14910}, abstractNote={AbstractIdentifying traits that facilitate species introductions and successful invasions of ecosystems represents a key issue in ecology. Following their establishment into new environments, many non‐native species exhibit phenotypic plasticity with post‐introduction changes in behaviour, morphology or life history traits that allow them to overcome the presumed loss of genetic diversity resulting in inbreeding and reduced adaptive potential. Here, we present a unique strategy in the invasive ant Brachyponera chinensis (Emery), in which inbreeding tolerance is a pre‐adapted trait for invasion success, allowing this ant to cope with genetic depletion following a genetic bottleneck. We report for the first time that inbreeding is not a consequence of the founder effect following introduction, but it is due to mating between sister queens and their brothers that pre‐exists in native populations which may have helped it circumvent the cost of invasion. We show that a genetic bottleneck does not affect the genetic diversity or the level of heterozygosity within colonies and suggest that generations of sib‐mating in native populations may have reduced inbreeding depression through purifying selection of deleterious alleles. This work highlights how a unique life history may pre‐adapt some species for biological invasions.}, number={23}, journal={MOLECULAR ECOLOGY}, author={Eyer, Pierre-Andre and Matsuura, Kenji and Vargo, Edward L. and Kobayashi, Kazuya and Yashiro, Toshihisa and Suehiro, Wataru and Himuro, Chihiro and Yokoi, Tomoyuki and Guenard, Benoit and Dunn, Robert R. and et al.}, year={2018}, month={Dec}, pages={4711–4724} }
 @article{jones_vargo_keefer_labadie_scherer_gallagher_gold_2017, title={Efficacy of Chlorantraniliprole in Controlling Structural Infestations of the Eastern Subterranean Termite in the USA}, volume={8}, ISSN={["2075-4450"]}, DOI={10.3390/insects8030092}, abstractNote={Subterranean termites are the most economically important structural pests in the USA, and the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Dictyoptera: Rhinotermitidae) is the most widely distributed species. Soil treatment with a liquid termiticide is a widely used method for controlling subterranean termites in structures. We assessed the efficacy of a nonrepellent termiticide, Altriset® (active ingredient: chlorantraniliprole), in controlling structural infestations of R. flavipes in Texas, North Carolina, and Ohio and determined the post-treatment fate of termite colonies in and around the structures. In all three states, microsatellite markers indicated that only one R. flavipes colony was infesting each structure. A single chlorantraniliprole treatment provided effective structural protection as there was no further evidence of termite activity in and on the majority of structures from approximately 1 month to 2 years post-treatment when the study concluded. Additionally, the treatment appeared to either severely reduce the infesting colony’s footprint at monitors in the landscape or eliminate colony members from these monitors. A supplemental spot-treatment was conducted at one house each in Texas and North Carolina at 5 and 6 months post-treatment, respectively; no termites were observed thereafter in these structures and associated landscaping. The number of colonies found exclusively in the landscape (not attacking the structure) varied among the states, with the largest number of colonies in Texas (0–4) and North Carolina (0–5) as compared to 0–1 in Ohio, the most northern state.}, number={3}, journal={INSECTS}, author={Jones, Susan C. and Vargo, Edward L. and Keefer, T. Chris and Labadie, Paul and Scherer, Clay W. and Gallagher, Nicola T. and Gold, Roger E.}, year={2017}, month={Sep} }
 @article{zhu_dhammi_kretschmar_vargo_apperson_roe_2018, title={Novel use of aliphatic n-methyl ketones as a fumigant and alternative to methyl bromide for insect control}, volume={74}, ISSN={["1526-4998"]}, DOI={10.1002/ps.4749}, abstractNote={AbstractBACKGROUNDFumigants like phosphine, methyl bromide and sulfuryl fluoride are highly effective for the control of structural, storage and agricultural arthropod pests. Unfortunately, many of these synthetic compounds are highly toxic to people, many pests have developed resistance to these compounds and methyl bromide, the ‘gold standard’ for fumigants, was de‐registered because of its contribution to depletion of the stratospheric ozone layer. Alternative fumigant chemistry is needed.RESULTSSeveral plant species produce n‐aliphatic methyl ketones to prevent plant herbivory. To examine the use of methyl ketones as a fumigant, structure–mortality studies were conducted using the red imported fire ant, Solenopsis invicta Buren, as a model. A new easy‐to‐use, inexpensive and disposable bioassay system was developed for this study. The LC50 values for heptanone, octanone, nonanone and undecanone were 4.27, 5.11, 5.26 and 8.21 µg/cm3 of ambient air, respectively. Although heptanone, octanone and nonanone were more effective than undecanone, subsequent research was conducted with 2‐undecanone because this compound already has US Environmental Protection Agency (EPA) registration as a biopesticide. In dose–response field studies, 12.4 mL of undecanone injected into mounds was the lowest application rate that produced no ant activity in the mound with no re‐establishment of ants. Reagent grade undecanone was more cost‐effective than methyl bromide for fire ants, adult German cockroaches and tobacco budworm eggs, but slightly more expensive for adult flour beetles.CONCLUSIONThe naturally occurring methyl ketone undecanone has the potential to be an alternative to current fumigants for a variety of pest applications. © 2017 Society of Chemical Industry}, number={3}, journal={PEST MANAGEMENT SCIENCE}, author={Zhu, Jiwei and Dhammi, Anirudh and Kretschmar, Jaap B. and Vargo, Edward L. and Apperson, Charles S. and Roe, R. Michael}, year={2018}, month={Mar}, pages={648–657} }
 @article{raab_moore_vargo_rose_raab_culbreth_burzumato_koyee_mccarthy_raffaele_et al._2016, title={New Introductions, Spread of Existing Matrilines, and High Rates of Pyrethroid Resistance Result in Chronic Infestations of Bed Bugs (Cimex lectularius L.) in Lower-Income Housing}, volume={11}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0117805}, DOI={10.1371/journal.pone.0117805}, abstractNote={Infestations of the common bed bug (Cimex lectularius L.) have increased substantially in the United States in the past 10–15 years. The housing authority in Harrisonburg, Virginia, conducts heat-treatments after bed bugs are detected in a lower-income housing complex, by treating each infested unit at 60°C for 4–6 hours. However, a high frequency of recurrent infestations called into question the efficacy of this strategy. Genetic analysis using Bayesian clustering of polymorphic microsatellite loci from 123 bed bugs collected from 23 units from May 2012 to April 2013 in one building indicated that (a) 16/21 (73%) infestations were genetically similar, suggesting ineffective heat-treatments or reintroductions from within the building or from a common external source, followed by local spread of existing populations; and (b) up to 5 of the infestations represented new genotypes, indicating that 5 new populations were introduced into this building in one year, assuming they were not missed in earlier screens. There was little to no gene flow among the 8 genetic clusters identified in the building. Bed bugs in the U.S. often possess one or both point mutations in the voltage-gated sodium channel, termed knockdown resistance (kdr), from valine to leucine (V419L) and leucine to isoleucine (L925I) that confer target-site resistance against pyrethroid insecticides. We found that 48/121 (40%) bed bugs were homozygous for both kdr mutations (L419/I925), and a further 59% possessed at least one of the kdr mutations. We conclude that ineffective heat treatments, new introductions, reintroductions and local spread, and an exceptionally high frequency of pyrethroid resistance are responsible for chronic infestations in lower-income housing. Because heat treatments fail to protect from reintroductions, and pesticide use has not decreased the frequency of infestations, preventing new introductions and early detection are the most effective strategies to avoid bed bug infestations in multistory apartment buildings.}, number={2}, journal={PLOS ONE}, publisher={Public Library of Science (PLoS)}, author={Raab, Ronald W. and Moore, Julia E. and Vargo, Edward L. and Rose, Lucy and Raab, Julie and Culbreth, Madeline and Burzumato, Gracie and Koyee, Aurvan and McCarthy, Brittany and Raffaele, Jennifer and et al.}, editor={Benoit, Joshua B.Editor}, year={2016}, month={Feb}, pages={e0117805} }
 @article{jacobson_nault_vargo_kennedy_2016, title={Restricted Gene Flow among Lineages of Thrips tabaci Supports Genetic Divergence Among Cryptic Species Groups}, volume={11}, ISSN={["1932-6203"]}, DOI={10.1371/journal.pone.0163882}, abstractNote={Knowledge of the relative influence of population- versus species-level genetic variation is important to understand patterns of phenotypic variation and ecological relationships that exist among and within morphologically indistinguishable cryptic species and subspecies. In the case of cryptic species groups that are pests, such knowledge is also essential for devising effective population management strategies. The globally important crop pest Thrips tabaci is a taxonomically difficult group of putatively cryptic species. This study examines population genetic structure of T. tabaci and reproductive isolation among lineages of this species complex using microsatellite markers and mitochondrial COI sequences. Overall, genetic structure supports T. tabaci as a cryptic species complex, although limited interbreeding occurs between different clonal groups from the same lineage as well as between individuals from different lineages. These results also provide evidence that thelytoky and arrhenotoky are not fixed phenotypes among members of different T. tabaci lineages that have been generally associated with either reproductive mode. Possible biological and ecological factors contributing to these observations are discussed.}, number={9}, journal={PLOS ONE}, author={Jacobson, Alana L. and Nault, Brian A. and Vargo, Edward L. and Kennedy, George G.}, year={2016}, month={Sep} }
 @article{haifig_vargo_labadie_costa-leonardo_2016, title={Unrelated secondary reproductives in the neotropical termite Silvestritermes euamignathus (Isoptera: Termitidae)}, volume={103}, ISSN={["1432-1904"]}, DOI={10.1007/s00114-015-1325-0}, abstractNote={A termite colony is usually founded by a pair of alates, the primary reproductives, which produce all the nestmates. In some species, secondary reproductives appear to either replace the primaries or supplement colony reproduction. In termites, secondary reproductives are generally ergatoids derived from workers or nymphoids derived from nymphs. Silvestritermes euamignathus is a termite species that forms multiple nymphoid reproductives, and to date it was hypothesized that these secondary reproductives were the progeny of the primary founding reproductives. We developed markers for 12 microsatellite loci and used COI mitochondrial DNA (mtDNA) to genotype 59 nymphoid neotenics found in a colony of S. euamignathus to test this hypothesis. Our results showed that nymphoids of S. euamignathus are not all siblings. The microsatellite analysis suggests that the secondary reproductives derived from a minimum of four different pairs of reproductives belonging to at least two different matrilines. This is the first record of non-sibling secondary reproductives occupying the same nest in a higher termite. These unrelated reproductives might be the result of either pleometrotic colony foundation or colony fusion.}, number={1-2}, journal={SCIENCE OF NATURE}, author={Haifig, Ives and Vargo, Edward L. and Labadie, Paul and Costa-Leonardo, Ana Maria}, year={2016}, month={Feb} }
 @article{booth_balvín_vargo_vilímová_schal_2015, title={Host association drives genetic divergence in the bed bug, Cimex lectularius}, volume={24}, ISSN={0962-1083}, url={http://dx.doi.org/10.1111/mec.13086}, DOI={10.1111/mec.13086}, abstractNote={AbstractGenetic differentiation may exist among sympatric populations of a species due to long‐term associations with alternative hosts (i.e. host‐associated differentiation). While host‐associated differentiation has been documented in several phytophagus insects, there are far fewer cases known in animal parasites. The bed bug, Cimex lectularius, a wingless insect, represents a potential model organism for elucidating the processes involved in host‐associated differentiation in animal parasites with relatively limited mobility. In conjunction with the expansion of modern humans from Africa into Eurasia, it has been speculated that bed bugs extended their host range from bats to humans in their shared cave domiciles throughout Eurasia. C. lectularius that associate with humans have a cosmopolitan distribution, whereas those associated with bats occur across Europe, often in human‐built structures. We assessed genetic structure and gene flow within and among populations collected in association with each host using mtDNA, microsatellite loci and knock‐down resistance gene variants. Both nuclear and mitochondrial data support a lack of significant contemporary gene flow between host‐specific populations. Within locations human‐associated bed bug populations exhibit limited genetic diversity and elevated levels of inbreeding, likely due to human‐mediated movement, infrequent additional introduction events per infestation, and pest control. In contrast, populations within bat roosts exhibit higher genetic diversity and lower levels of relatedness, suggesting populations are stable with temporal fluctuations due to host dispersal and bug mortality. In concert with previously published evidence of morphological and behavioural differentiation, the genetic data presented here suggest C. lectularius is currently undergoing lineage divergence through host association.}, number={5}, journal={Molecular Ecology}, publisher={Wiley}, author={Booth, Warren and Balvín, Ondřej and Vargo, Edward L. and Vilímová, Jitka and Schal, Coby}, year={2015}, month={Feb}, pages={980–992} }
 @misc{perdereau_bagneres_vargo_baudouin_xu_labadie_dupont_dedeine_2015, title={Relationship between invasion success and colony breeding structure in a subterranean termite}, volume={24}, ISSN={["1365-294X"]}, DOI={10.1111/mec.13094}, abstractNote={AbstractFactors promoting the establishment and colonization success of introduced populations in new environments constitute an important issue in biological invasions. In this context, the respective role of pre‐adaptation and evolutionary changes during the invasion process is a key question that requires particular attention. This study compared the colony breeding structure (i.e. number and relatedness among reproductives within colonies) in native and introduced populations of the subterranean pest termite, Reticulitermes flavipes. We generated and analysed a data set of both microsatellite and mtDNA loci on termite samples collected in three introduced populations, one in France and two in Chile, and in the putative source population of French and Chilean infestations that has recently been identified in New Orleans, LA. We also provided a synthesis combining our results with those of previous studies to obtain a global picture of the variation in breeding structure in this species. Whereas most native US populations are mainly composed of colonies headed by monogamous pairs of primary reproductives, all introduced populations exhibit a particular colony breeding structure that is characterized by hundreds of inbreeding reproductives (neotenics) and by a propensity of colonies to fuse, a pattern shared uniquely with the population of New Orleans. These characteristics are comparable to those of many invasive ants and are discussed to play an important role during the invasion process. Our finding that the New Orleans population exhibits the same breeding structure as its related introduced populations suggests that this native population is pre‐adapted to invade new ranges.}, number={9}, journal={MOLECULAR ECOLOGY}, author={Perdereau, E. and Bagneres, A. -G. and Vargo, E. L. and Baudouin, G. and Xu, Y. and Labadie, P. and Dupont, S. and Dedeine, F.}, year={2015}, month={May}, pages={2125–2142} }
 @article{vargo_crissman_booth_santangelo_mukha_schal_2014, title={Hierarchical Genetic Analysis of German Cockroach (Blattella germanica) Populations from within Buildings to across Continents}, volume={9}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0102321}, DOI={10.1371/journal.pone.0102321}, abstractNote={Understanding the population structure of species that disperse primarily by human transport is essential to predicting and controlling human-mediated spread of invasive species. The German cockroach (Blattella germanica) is a widespread urban invader that can actively disperse within buildings but is spread solely by human-mediated dispersal over longer distances; however, its population structure is poorly understood. Using microsatellite markers we investigated population structure at several spatial scales, from populations within single apartment buildings to populations from several cities across the U.S. and Eurasia. Both traditional measures of genetic differentiation and Bayesian clustering methods revealed increasing levels of genetic differentiation at greater geographic scales. Our results are consistent with active dispersal of cockroaches largely limited to movement within a building. Their low levels of genetic differentiation, yet limited active spread between buildings, suggests a greater likelihood of human-mediated dispersal at more local scales (within a city) than at larger spatial scales (within and between continents). About half the populations from across the U.S. clustered together with other U.S. populations, and isolation by distance was evident across the U.S. Levels of genetic differentiation among Eurasian cities were greater than those in the U.S. and greater than those between the U.S. and Eurasia, but no clear pattern of structure at the continent level was detected. MtDNA sequence variation was low and failed to reveal any geographical structure. The weak genetic structure detected here is likely due to a combination of historical admixture among populations and periodic population bottlenecks and founder events, but more extensive studies are needed to determine whether signatures of global movement may be present in this species.}, number={7}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Vargo, Edward L. and Crissman, Jonathan R. and Booth, Warren and Santangelo, Richard G. and Mukha, Dmitry V. and Schal, Coby}, editor={Adelman, Zach N.Editor}, year={2014}, month={Jul}, pages={e102321} }
 @article{vargo_2014, title={Molecular ecology meets urban entomology: How molecular biology is changing urban pest management}, journal={Urban Insect Pests: Sustainable Management Strategies}, author={Vargo, E. L.}, year={2014}, pages={166–180} }
 @article{terrapon_li_robertson_ji_meng_booth_chen_childers_glastad_gokhale_et al._2014, title={Molecular traces of alternative social organization in a termite genome}, volume={5}, journal={Nature Communications}, author={Terrapon, N. and Li, C. and Robertson, H. M. and Ji, L. and Meng, X. H. and Booth, W. and Chen, Z. S. and Childers, C. P. and Glastad, K. M. and Gokhale, K. and et al.}, year={2014} }
 @article{husseneder_garner_huang_booth_vargo_2013, title={Characterization of Microsatellites for Population Genetic Analyses of the Fungus-Growing Termite (Isoptera: Termitidae)}, volume={42}, ISSN={["1938-2936"]}, DOI={10.1603/en13059}, abstractNote={ABSTRACT 
 The fungus-growing subterranean termite Odontotermes formosanus Shiraki (Isoptera: Termitidae) is a destructive pest in Southeast Asia. To facilitate studies on the biology, ecology, and control of O. formosanus, we isolated and characterized nine novel microsatellite loci from a mixed partial genomic library of O. formosanus and the sympatric Macrotermes barneyi Light enriched for di-, tri-, and tetranucleotide repeats. We screened these loci in three populations of O. formosanus from China. All loci were polymorphic. Three loci showed heterozygote deficit possibly because of the presence of null alleles. The remaining six loci with 4–15 alleles per locus and an average observed heterozygosity of 0.15–0.60 across populations were used for population genetic analysis. Populations from different provinces (Guangdong, Jiangxi, and Hubei) were genetically differentiated, but the genetic distance between populations was surprisingly small (FST: 0.03–0.08) and the gene flow was considerable (Nem: 3–8), despite the geographical distance being >300 km. Genetic diversity within populations was low (allelic richness: 5.1–6.3) compared with other subterranean dwelling termites, but consistent with the diversity in species of the family Termitidae. Microsatellite markers developed for O. formosanus will allow further studies to examine the phylogeography, population genetic and colony breeding structure, dispersal ranges, and size of foraging territories in this and closely related species, as well as aid in assessing treatment success.}, number={5}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Husseneder, Claudia and Garner, Susan P. and Huang, Qiuying and Booth, Warren and Vargo, Edward L.}, year={2013}, month={Oct}, pages={1092–1099} }
 @article{vargo_leniaud_swoboda_diamond_weiser_miller_bagneres_2013, title={Clinal variation in colony breeding structure and level of inbreeding in the subterranean termites Reticulitermes flavipes and R.grassei}, volume={22}, ISSN={["1365-294X"]}, DOI={10.1111/mec.12166}, abstractNote={AbstractSocial insects exhibit remarkable variation in their colony breeding structures, both within and among species. Ecological factors are believed to be important in shaping reproductive traits of social insect colonies, yet there is little information linking specific environmental variables with differences in breeding structure. Subterranean termites (Rhinotermitidae) show exceptional variation in colony breeding structure, differing in the number of reproductives and degree of inbreeding; colonies can be simple families headed by a single pair of monogamous reproductives (king and queen) or they can be extended families headed by multiple inbreeding neotenic reproductives (wingless individuals). Using microsatellite markers, we characterized colony breeding structure and levels of inbreeding in populations over large parts of the range of the subterranean termites Reticulitermes flavipes in the USA and R. grassei in Europe. Combining these new data with previous results on populations of both species, we found that latitude had a strong effect on the proportion of extended‐family colonies in R. flavipes and on levels of inbreeding in both species. We examined the effect of several environmental variables that vary latitudinally; while the degree of inbreeding was greatest in cool, moist habitats in both species, seasonality affected the species differently. Inbreeding in R. flavipes was most strongly associated with climatic variables (mean annual temperature and seasonality), whereas nonclimatic variables, including the availability of wood substrate and soil composition, were important predictors of inbreeding in R. grassei. These results are the first showing that termite breeding structure is shaped by local environmental factors and that species can vary in their responses to these factors.}, number={5}, journal={MOLECULAR ECOLOGY}, author={Vargo, Edward L. and Leniaud, Laurianne and Swoboda, Lois E. and Diamond, Sarah E. and Weiser, Michael D. and Miller, Dini M. and Bagneres, Anne-Genevieve}, year={2013}, month={Mar}, pages={1447–1462} }
 @article{kobayashi_hasegawa_yamamoto_kawatsu_vargo_yoshimura_matsuura_2013, title={Sex ratio biases in termites provide evidence for kin selection}, volume={4}, ISSN={["2041-1723"]}, DOI={10.1038/ncomms3048}, abstractNote={Inclusive fitness theory, also known as kin selection theory, is the most general expansion of Darwin's natural selection theory. It is supported by female-biased investment by workers in the social Hymenoptera where relatedness to sisters is higher than to brothers because of haplodiploidy. However, a strong test of the theory has proven difficult in diploid social insects because they lack such relatedness asymmetry. Here we show that kin selection can result in sex ratio bias in eusocial diploids. Our model predicts that allocation will be biased towards the sex that contributes more of its genes to the next generation when sex-asymmetric inbreeding occurs. The prediction matches well with the empirical sex allocation of Reticulitermes termites where the colony king can be replaced by a queen’s son. Our findings open broad new avenues to test inclusive fitness theory beyond the well-studied eusocial Hymenoptera. Kin selection predicts female-biased sex ratios in haplodiploid eusocial insects because sisters are more related to each other than to their brothers. Here the authors provide evidence that sex ratio bias also occurs in diploid eusocial insects, which do not show asymmetric relatedness.}, journal={NATURE COMMUNICATIONS}, author={Kobayashi, Kazuya and Hasegawa, Eisuke and Yamamoto, Yuuka and Kawatsu, Kazutaka and Vargo, Edward L. and Yoshimura, Jin and Matsuura, Kenji}, year={2013}, month={Jun} }
 @article{saenz_maggi_breitschwerdt_kim_vargo_schal_2013, title={Survey of Bartonella spp. in U.S. Bed Bugs Detects Burkholderia multivorans but Not Bartonella}, volume={8}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0073661}, DOI={10.1371/journal.pone.0073661}, abstractNote={Bed bugs (Cimex lectularius L.) have resurged in the United States and globally. Bed bugs are hematophagous ectoparasites of humans and other animals, including domestic pets, chickens, and bats, and their blood feeding habits contribute to their potential as disease vectors. Several species of Bartonella are re-emergent bacterial pathogens that also affect humans, domestic pets, bats and a number of other wildlife species. Because reports of both bed bugs and Bartonella have been increasing in the U.S., and because their host ranges can overlap, we investigated whether the resurgences of these medically important pathogens and their potential vector might be linked, by screening for Bartonella spp. in bed bugs collected from geographic areas where these pathogens are prevalent and from bed bugs that have been in culture in the laboratory for several years. We screened a total of 331 bed bugs: 316 bed bugs from 36 unique collections in 29 geographic locations in 13 states, 10 bed bugs from two colonies maintained in the laboratory for 3 yr, and 5 bed bugs from a colony that has been in culture since before the recent resurgence of bed bugs. Bartonella spp. DNA was screened using a polymerase chain reaction assay targeting the 16S–23S rRNA intergenic transcribed spacer region. Bartonella DNA was not amplified from any bed bug, but five bed bugs from four different apartments of an elderly housing building in North Carolina contained DNA sequences that corresponded to Burkholderia multivorans, an important pathogen in nosocomial infections that was not previously linked to an arthropod vector.}, number={9}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Saenz, Virna L. and Maggi, Ricardo G. and Breitschwerdt, Edward B. and Kim, Jung and Vargo, Edward L. and Schal, Coby}, editor={Palli, Subba ReddyEditor}, year={2013}, month={Sep}, pages={e73661} }
 @article{jacobson_booth_vargo_kennedy_2013, title={Thrips tabaci Population Genetic Structure and Polyploidy in Relation to Competency as a Vector of Tomato Spotted Wilt Virus}, volume={8}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0054484}, DOI={10.1371/journal.pone.0054484}, abstractNote={Knowledge of population-level genetic differences can help explain variation among populations of insect vectors in their role in the epidemiology of specific viruses. Variation in competency to transmit Tomato spotted wilt virus (TSWV) that exists among populations of Thrips tabaci has been associated with the presence of cryptic species that exhibit different modes of reproduction and host ranges. However, recent findings suggest that vector competency of T. tabaci at any given location depends on the thrips and virus populations that are present. This study characterizes the population genetic structure of T. tabaci collected from four locations in North Carolina and examines the relationship between population genetic structure and variation in TSWV transmission by T. tabaci. Mitochondrial COI sequence analysis revealed the presence of two genetically distinct groups with one characterized by thelytokous, parthenogenetic reproduction and the other by arrhenotokous, sexual reproduction. Using a set of 11 microsatellite markers that we developed to investigate T. tabaci population genetic structure, we identified 17 clonal groups and found significant genetic structuring among the four NC populations that corresponded to the geographic locations where the populations were collected. Application of microsatellite markers also led to the discovery of polyploidy in this species. All four populations contained tetraploid individuals, and three contained both diploid and tetraploid individuals. Analysis of variation in transmission ofTSWV among isofemale lines initiated with individuals used in this study revealed that ‘clone assignment,’ ‘virus isolate’ and their interaction significantly influenced vector competency. These results highlight the importance of interactions between specific T. tabaci clonal types and specific TSWV isolates underlying transmission of TSWV by T. tabaci.}, number={1}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Jacobson, Alana L. and Booth, Warren and Vargo, Edward L. and Kennedy, George G.}, editor={Belshaw, RobertEditor}, year={2013}, month={Jan}, pages={e54484} }
 @article{vargo_parman_2012, title={Effect of Fipronil on Subterranean Termite Colonies (Isoptera: Rhinotermitidae) in the Field}, volume={105}, ISSN={["0022-0493"]}, DOI={10.1603/ec11155}, abstractNote={ABSTRACT 
 To assess possible colony-level effects of fipronil, a commonly used nonrepellent termiticide, we conducted a field study of eight houses in the Raleigh, NC, area with infestations of the eastern subterranean termite Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae). We installed an extensive grid of in-ground monitoring stations on each property (mean = 68.6 monitors per property) and collected samples from these stations as well as from mud tubes in the structure and wood debris in the yard for ≈6 mo. We genotyped all samples by using microsatellite markers to identify the number and locations of colonies present on each property. Houses were treated with either a full treatment (n = 5) or exterior/localized interior treatment (n = 3). After treatment, the monitors were checked monthly for 3 mo and then quarterly for 3 yr to track the fate of colonies. Wood debris in natural areas was checked semiannually for 3 yr. All 11 of the treated colonies (those attacking structures) disappeared within 90 d of treatment and were not found again. These colonies were presumed to be eliminated. In contrast, 60% of untreated colonies (those located >6 m from the foundation wall at the time of treatment) continued to persist throughout the study, as did 25% of the likely treated colonies (those occupying monitors 0.5 m from the foundation wall where the treatment was applied). Our results provide strong evidence for potent colony wide effects of fipronil on subterranean termites leading to colony suppression and likely colony elimination under field conditions.}, number={2}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Vargo, Edward L. and Parman, Vincent}, year={2012}, month={Apr}, pages={523–532} }
 @article{eger_lees_neese_atkinson_thoms_messenger_demark_lee_vargo_tolley_2012, title={Elimination of Subterranean Termite (Isoptera: Rhinotermitidae) Colonies Using a Refined Cellulose Bait Matrix Containing Noviflumuron When Monitored and Replenished Quarterly}, volume={105}, ISSN={["0022-0493"]}, DOI={10.1603/ec11027}, abstractNote={ABSTRACT Using a quarterly (3-mo) monitoring and bait-replenishment interval, 122 subterranean termite colonies throughout the United States were baited with a refined cellulose bait matrix containing 0.5% noviflumuron. All colonies were eliminated in less than 1 yr after initiation of baiting as determined by long-term monitoring and genetic markers. Sixty-three percent of the colonies were eliminated during the first quarter after the initiation of baiting and 77% of colonies were eliminated after consuming two bait tubes or less. This suggests that a single baiting cycle and bait installed in response to a single active monitoring device were sufficient to eliminate the majority of colonies. Although termites temporarily abandoned stations after depleting bait, workers resumed feeding when baits were replenished. Colonies that consumed large amounts of bait before elimination foraged into multiple stations, thus allowing adequate amounts of bait to sustain feeding. The time to eliminate termite colonies with bait replenished quarterly was similar to that previously reported for laminated cellulose bait replenished monthly. Our data support the conclusion that extending the bait replenishment interval from monthly to quarterly for bait tubes with refined cellulose containing 0.5% noviflumuron did not adversely impact colony elimination.}, number={2}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Eger, J. E., Jr. and Lees, M. D. and Neese, P. A. and Atkinson, T. H. and Thoms, E. M. and Messenger, M. T. and Demark, J. J. and Lee, L. -C. and Vargo, E. L. and Tolley, M. P.}, year={2012}, month={Apr}, pages={533–539} }
 @article{vasquez_vargo_silverman_2012, title={Fusion Between Southeastern United States Argentine Ant Colonies and Its Effect on Colony Size and Productivity}, volume={105}, ISSN={["1938-2901"]}, DOI={10.1603/an11114}, abstractNote={Abstract
               The ecological success of invasive ants has been linked to their ability to form expansive supercolonies. In the Argentine ant, Linepithema humile (Mayr), increased productivity and competitive ability of introduced supercolonies in several places, e.g., California and southern Europe, has been linked to high population densities that could have been attained via fusion of nonaggressive and genetically similar nests. Recently, we have found that introduced L. humile colonies in the southeastern United States, which have higher levels of intraspecific aggression and genetic diversity than those in California and southern Europe, sometimes also fuse; yet it is unclear what the longer term consequences of such colony fusion might be. In this study, we examined whether fusion of these southeastern United States L. humile colonies results in larger colonies by recording colony size and productivity in pairs that fused and in pairs that did not fuse. After 6 mo, colonies that fused produced 47% more workers and had twice as many queens as colony pairs that did not fuse. Also, fused colonies had an overall per capita colony productivity (number of brood and workers produced per queen and per worker) comparable to that of nonfused pairs and unpaired controls. Furthermore, all queens contributed to worker pupae production in fused colonies. Thus, fusion of initially aggressive southeastern United States L. humile colonies results in colonies with higher worker number without decreasing per capita productivity. Moreover, offspring contribution by all queens in fused colonies may alter colony genotypic composition resulting in reduced intraspecific aggression that in turn promotes further fusion. This process may be relevant to the establishment of incipient colonies in areas where multiple introductions have occurred.}, number={2}, journal={ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA}, author={Vasquez, Gissella M. and Vargo, Edward L. and Silverman, Jules}, year={2012}, month={Mar}, pages={268–274} }
 @article{saenz_booth_schal_vargo_2012, title={Genetic Analysis of Bed Bug Populations Reveals Small Propagule Size Within Individual Infestations but High Genetic Diversity Across Infestations From the Eastern United States}, volume={49}, ISSN={0022-2585 1938-2928}, url={http://dx.doi.org/10.1603/ME11202}, DOI={10.1603/me11202}, abstractNote={ABSTRACT 
 Bed bugs (Cimex lectularius L.) are a resurgent pest worldwide and infestations within the United States are increasing at a rapid rate. Because of the physical and psychological discomfort inflicted by their blood feeding habits, and allergies and secondary infections associated with bites, bed bugs are recognized as a significant public health problem. Although bed bug infestations are spreading and becoming more prevalent, we have a poor understanding of their dispersal patterns and sources of infestation. To help fill this gap, we conducted a genetic study of 21 bed bug infestations from the eastern United States, nearly all of which came from single rooms within residences. We genotyped samples comprised of 8–10 individuals per infestation at nine polymorphic microsatellite loci. Despite high genetic diversity across all infestations, with 5–17 alleles per locus (mean = 10.3 alleles per locus), we found low genetic diversity (1–4 alleles per locus) within all but one of the infestations. These results suggest that nearly all the studied infestations were started by a small propagule possibly consisting of a singly mated female and/or her progeny, or a female mated with multiple males that were highly related to her. All infestations were strongly genetically differentiated from each other (mean pairwise F ST between populations = 0.68) and we did not find strong evidence of a geographic pattern of genetic structure, indicating infestations located in closer proximity to each other were nearly as genetically differentiated as those located hundreds of kilometers away. The high level of genetic diversity across infestations from the eastern United States together with the lack of geographically organized structure is consistent with multiple introductions into the United States from foreign sources.}, number={4}, journal={Journal of Medical Entomology}, publisher={Oxford University Press (OUP)}, author={Saenz, Virna L. and Booth, Warren and Schal, Coby and Vargo, Edward L.}, year={2012}, month={Jul}, pages={865–875} }
 @article{jacobson_johnston_rotenberg_whitfield_booth_vargo_kennedy_2012, title={Genome size and ploidy of Thysanoptera}, volume={22}, ISSN={0962-1075}, url={http://dx.doi.org/10.1111/j.1365-2583.2012.01165.x}, DOI={10.1111/j.1365-2583.2012.01165.x}, abstractNote={AbstractFlow cytometry was used to study the genome sizes and ploidy levels for four thrips species: Franklinothrips orizabensis Johansen (Thysanoptera: Aeolothripidae), Frankliniella occidentalis Pergande, Frankliniella fusca Hinds, and Thrips tabaci Lindeman (Thysanoptera: Thripidae). F. orizabensis males and females had 1C genome sizes of 426 Mb and 422 Mb, respectively. Male and female F. fusca had 1C genome sizes of 392 Mb and 409 Mb, whereas F. occidentalis males and females had smaller 1C genomes that were 345 Mb and 337 Mb, respectively. Male F. orizabensis, F. occidentalis and F. fusca were haploid and females diploid. Five isofemale lines of T. tabaci, initiated from parthenogenetic, thelytokous females and collected from different locations in North Carolina, were included in this study; no males were available. One isofemale line was diploid with a genome size of 1C = 310 Mb, and the other four had a mean genome size of 1C = 482 Mb, which is consistent with evidence from microsatellite data of diploidy and polyploidy, respectively, in these same five thelytokous lines. This is the first study to produce genome size estimates for thysanopteran species, and report polyploidy in T. tabaci populations.}, number={1}, journal={Insect Molecular Biology}, publisher={Wiley}, author={Jacobson, A. L. and Johnston, J. S. and Rotenberg, D. and Whitfield, A. E. and Booth, W. and Vargo, E. L. and Kennedy, G. G.}, year={2012}, month={Nov}, pages={12–17} }
 @article{perdereau_bagneres_bankhead-dronnet_dupont_zimmermann_vargo_dedeine_2013, title={Global genetic analysis reveals the putative native source of the invasive termite, Reticulitermes flavipes, in France}, volume={22}, ISSN={["1365-294X"]}, DOI={10.1111/mec.12140}, abstractNote={AbstractBiological invasions are recognized as a major threat to both natural and managed ecosystems. Phylogeographic and population genetic analyses can provide information about the geographical origins and patterns of introduction and explain the causes and mechanisms by which introduced species have become successful invaders. Reticulitermes flavipes is a North American subterranean termite that has been introduced into several areas, including France where introduced populations have become invasive. To identify likely source populations in the USA and to compare the genetic diversity of both native and introduced populations, an extensive molecular genetic study was undertaken using the COII region of mtDNA and 15 microsatellite loci. Our results showed that native northern US populations appeared well differentiated from those of the southern part of the US range. Phylogenetic analysis of both mitochondrial and nuclear markers showed that French populations probably originated from southeastern US populations, and more specifically from Louisiana. All of the mtDNA haplotypes shared between the United States and France were found in Louisiana. Compared to native populations in Louisiana, French populations show lower genetic diversity at both mtDNA and microsatellite markers. These findings are discussed along with the invasion routes of R. flavipes as well as the possible mechanisms by which French populations have evolved after their introduction.}, number={4}, journal={MOLECULAR ECOLOGY}, author={Perdereau, E. and Bagneres, A-G. and Bankhead-Dronnet, S. and Dupont, S. and Zimmermann, M. and Vargo, E. L. and Dedeine, F.}, year={2013}, month={Feb}, pages={1105–1119} }
 @article{booth_saenz_santangelo_wang_schal_vargo_2012, title={Molecular Markers Reveal Infestation Dynamics of the Bed Bug (Hemiptera: Cimicidae) Within Apartment Buildings}, volume={49}, ISSN={0022-2585 1938-2928}, url={http://dx.doi.org/10.1603/ME11256}, DOI={10.1603/me11256}, abstractNote={ABSTRACT 
 The bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), has experienced an extraordinary global resurgence in recent years, the reasons for which remain poorly understood. Once considered a pest of lower socioeconomic classes, bed bugs are now found extensively across all residential settings, with widespread infestations established in multiapartment buildings. Within such buildings, understanding the population genetic structure and patterns of dispersal may prove critical to the development of effective control strategies. Here, we describe the development of 24 high-resolution microsatellite markers through next generation 454 pyrosequencing and their application to elucidate infestation dynamics within three multistory apartment buildings in the United States. Results reveal contrasting characteristics potentially representative of geographic or locale differences. In Raleigh, NC, an infestation within an apartment building seemed to have started from a single introduction followed by extensive spread. In Jersey City, NJ, two or more introductions followed by spread are evident in two buildings. Populations within single apartments in all buildings were characterized by high levels of relatedness and low levels of diversity, indicative of foundation from small, genetically depauperate propagules. Regardless of the number of unique introductions, genetic data indicate that spread within buildings is extensive, supporting both active and human-mediated dispersal within and between adjacent rooms or apartments spanning multiple floors.}, number={3}, journal={Journal of Medical Entomology}, publisher={Oxford University Press (OUP)}, author={Booth, Warren and Saenz, Virna L. and Santangelo, Richard G. and Wang, Changlu and Schal, Coby and Vargo, Edward L.}, year={2012}, month={May}, pages={535–546} }
 @article{singham_vargo_booth_othman_lee_2012, title={Polymorphic Microsatellite Loci From an Indigenous Asian Fungus-Growing Termite, Macrotermes gilvus (Blattodea: Termitidae) and Cross Amplification in Related Taxa}, volume={41}, ISSN={["1938-2936"]}, DOI={10.1603/en11228}, abstractNote={ABSTRACT The fungus- growing termite, Macrotermes gilvus (Hagen), an indigenous species from Southeast Asia distributed from Myanmar to Indonesia and the Philippines, offers great potential as an ecological model system to elucidate the effects of geography on gene flow within this region. We used next generation sequencing (Roche 454 pyrosequencing) to identify microsatellite markers from the genomic DNA of M. gilvus. A modest sequencing volume generated 34,122 reads, with 1,212 (3.6%) reads contains microsatellites with di-, tri-, tetra-, penta-, and hexa-nucleotide repeat motifs. Thirtyseven loci were selected for primer development and tested for polymorphism across 22 colonies of M. gilvus. Eleven loci were found to be polymorphic with 2–4 alleles per locus. Observed and expected heterozygosities ranged between 0.091–0.727 and 0.090–0.540, respectively. Cross taxa amplification was successful across a panel of four related termite species and four multiplex groups were designed for future population genetic studies. These markers will open new avenues for the study of phylogeography and population genetics of this fungus-growing termite. This study also has effectively demonstrated the use of 454 pyrosequencing for the rapid development of informative microsatellite markers from a termite genome.}, number={2}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Singham, G. Veera and Vargo, Edward L. and Booth, Warren and Othman, Ahmad Sofiman and Lee, Chow-Yang}, year={2012}, month={Apr}, pages={426–431} }
 @article{vargo_labadie_matsuura_2012, title={Asexual queen succession in the subterranean termite Reticulitermes virginicus}, volume={279}, DOI={10.1098/rspb.2011.1030}, abstractNote={
            Termite colonies are founded by a pair of primary reproductives. In many species, including subterranean termites (family Rhinotermitidae), the primary king and queen can be succeeded by neotenic reproductives that are produced from workers or nymphs within the colony. It is generally believed that these neotenics inbreed within the colony, sometimes for many generations. Here, we show that primary queens of the North American subterranean termite,
            Reticulitermes virginicus
            , are replaced by numerous parthenogenetically produced female neotenics. We collected functional female neotenics from five colonies of
            R. virginicus
            in North Carolina and Texas, USA. Genetic analysis at eight microsatellite loci showed that 91–100% of the neotenics present within a colony were homozygous at all loci, indicating that they were produced through automictic parthenogenesis with terminal fusion. In contrast, workers, soldiers and alates were almost exclusively sexually produced by mating between the female neotenics and a single king. This is the second termite species shown to undergo asexual queen succession, a system first described in the Japanese species,
            Reticulitermes speratus
            . Thus, the conditional use of sexual and asexual reproduction to produce members of different castes may be widespread within
            Reticulitermes
            and possibly other subterranean termites.
          }, number={1729}, journal={Proceedings of the Royal Society of London. Series B}, author={Vargo, E. L. and Labadie, P. E. and Matsuura, K.}, year={2012}, pages={813–819} }
 @article{booth_million_reynolds_burghardt_vargo_schal_tzika_schuett_2011, title={Consecutive Virgin Births in the New World Boid Snake, the Colombian Rainbow Boa, Epicrates maurus}, volume={102}, ISSN={1465-7333 0022-1503}, url={http://dx.doi.org/10.1093/jhered/esr080}, DOI={10.1093/jhered/esr080}, abstractNote={Until recently, facultative automictic parthenogenesis within the squamate reptiles exhibiting ZZ:ZW genetic sex determination has resulted in single reproductive events producing male (ZZ) or female (ZW) offspring. With the recent discovery of viable parthenogenetically produced female (WW) Boa constrictors, the existence of further parthenogenetic events resulting in WW females was questioned. Here, we provide genetic evidence for consecutive virgin births by a female Colombian rainbow boa (Epicrates maurus), resulting in the production of WW females likely through terminal fusion automixis. Samples were screened at 22 microsatellite loci with 12 amplifying unambiguous products. Of these, maternal heterozygosity was observed in 4, with the offspring differentially homozygous at each locus. This study documents the first record of parthenogenesis within the genus Epicrates, a second within the serpent lineage Boidae, and the third genetically confirmed case of consecutive virgin births of viable offspring within any vertebrate lineage. Unlike the recent record in Boa constrictors, the female described here was isolated from conspecifics from birth, demonstrating that males are not required to stimulate parthenogenetic reproduction in this species and possibly other Boas.}, number={6}, journal={Journal of Heredity}, publisher={Oxford University Press (OUP)}, author={Booth, Warren and Million, Larry and Reynolds, R. Graham and Burghardt, Gordon M. and Vargo, Edward L. and Schal, Coby and Tzika, Athanasia C. and Schuett, Gordon W.}, year={2011}, month={Aug}, pages={759–763} }
 @article{husseneder_simms_delatte_wang_grace_vargo_2012, title={Genetic diversity and colony breeding structure in native and introduced ranges of the Formosan subterranean termite, Coptotermes formosanus}, volume={14}, ISSN={["1573-1464"]}, DOI={10.1007/s10530-011-0087-7}, abstractNote={The Formosan subterranean termite, Coptotermes formosanus is recognized as one of the most important invasive pest species. Originating from China, C. formosanus has spread to many tropical and subtropical regions around the globe in the last 400 years, including Japan, Hawaii and the continental USA. Although the current distribution is well documented, information about the patterns of invasion and effects of introduction on the population genetics of this species is largely lacking. We analyzed the genetic structure of populations from two native populations (Guangdong and Hunan provinces, China) and two introduced populations (Maui and Kauai, Hawaii) using microsatellite genotyping. We also reanalyzed published data of additional populations from China, Japan, Hawaii, and the continental USA. The population from Hunan, the earliest introduction outside of China (Japan) and the first introduction to the continental USA (South Carolina) showed little genetic similarity with any of the native or introduced populations investigated. However, populations from Oahu (HI), New Orleans (LA) and Rutherford County (NC) showed close similarity. In general, genetic patterns suggest multiple introductions to the USA, with, for example, two separate introductions to the island of Maui. Bottleneck effects were detected in almost all recent introductions (after 1940). All populations in the introduced range showed lower genetic diversity than those in the native range. However, this low genetic diversity did not result in the formation of polygynous supercolonies as has been described for other invasive termite and ant species.}, number={2}, journal={BIOLOGICAL INVASIONS}, author={Husseneder, Claudia and Simms, Dawn M. and Delatte, Jennifer R. and Wang, Changlu and Grace, J. Kenneth and Vargo, Edward L.}, year={2012}, month={Feb}, pages={419–437} }
 @misc{abbot_abe_alcock_alizon_alpedrinha_andersson_andre_baalen_balloux_balshine_et al._2011, title={Inclusive fitness theory and eusociality}, volume={471}, number={7339}, journal={Nature}, author={Abbot, P. and Abe, J. and Alcock, J. and Alizon, S. and Alpedrinha, J. A. C. and Andersson, M. and Andre, J. B. and Baalen, M. and Balloux, F. and Balshine, S. and et al.}, year={2011}, pages={E1–4} }
 @article{booth_brent_calleri_rosengaus_traniello_vargo_2012, title={Population genetic structure and colony breeding system in dampwood termites (Zootermopsis angusticollis and Z. nevadensis nuttingi)}, volume={59}, ISSN={["1420-9098"]}, DOI={10.1007/s00040-011-0198-2}, number={1}, journal={INSECTES SOCIAUX}, author={Booth, W. and Brent, C. S. and Calleri, D. V. and Rosengaus, R. B. and Traniello, J. F. A. and Vargo, E. L.}, year={2012}, month={Feb}, pages={127–137} }
 @article{parman_vargo_2010, title={Colony-Level Effects of Imidacloprid in Subterranean Termites (Isoptera: Rhinotermitidae)}, volume={103}, ISSN={["1938-291X"]}, DOI={10.1603/ec09386}, abstractNote={ABSTRACT We determined the impact of imidacloprid (Premise) on colonies of Reticulitermes spp. (Isoptera: Rhinotermitidae) through soil applications in the field. We selected 11 houses in the Raleigh, NC, area with active termite infestations. In-ground monitoring stations (mean = 75.9 stations) were installed around each house, and samples of termites visiting the monitors, in mud tubes, as well as samples from wood debris in the yard, were collected monthly for up to 14 mo to determine the numbers and locations of colonies present before treatment. We used microsatellite genetic markers to identify individual colonies present on each property. All houses were treated with Premise 75 WSP by using an exterior perimeter/interior spot treatment. After treatment, termite samples were collected monthly for 3 mo and then quarterly for 2 yr to track the fate of colonies. Of the 12 treated colonies (those attacking structures), 75% disappeared within 90 d and were not detected again. In contrast, only 25% of 48 untreated colonies (located 2 m or further from the treatment zone) and 40% of the six likely treated colonies (located within 0.5 m of the treatment zone but not known to be attacking the structure) were not detected again during the study. Our findings are consistent with strong colony-level effects of soil treatments with imidacloprid, resulting in the suppression or elimination of Reticulitermes spp. colonies in many cases.}, number={3}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Parman, Vincent and Vargo, Edward L.}, year={2010}, month={Jun}, pages={791–798} }
 @article{booth_johnson_moore_schal_vargo_2010, title={Evidence for viable, non-clonal but fatherless Boa constrictors}, volume={7}, ISSN={1744-9561 1744-957X}, url={http://dx.doi.org/10.1098/rsbl.2010.0793}, DOI={10.1098/rsbl.2010.0793}, abstractNote={
            Parthenogenesis in vertebrates is considered an evolutionary novelty. In snakes, all of which exhibit genetic sex determination with ZZ : ZW sex chromosomes, this rare form of asexual reproduction has failed to yield viable female WW offspring. Only through complex experimental manipulations have WW females been produced, and only in fish and amphibians. Through microsatellite DNA fingerprinting, we provide the first evidence of facultative parthenogenesis in a
            Boa constrictor
            , identifying multiple, viable, non-experimentally induced females for the first time in any vertebrate lineage. Although the elevated homozygosity of the offspring in relation to the mother suggests that the mechanism responsible may be terminal fusion automixis, no males were produced, potentially indicating maternal sex chromosome hemizygosity (WO). These findings provide the first evidence of parthenogenesis in the family Boidae (Boas), and suggest that WW females may be more common within basal reptilian lineages than previously assumed.
          }, number={2}, journal={Biology Letters}, publisher={The Royal Society}, author={Booth, Warren and Johnson, Daniel H. and Moore, Sharon and Schal, Coby and Vargo, Edward L.}, year={2010}, month={Nov}, pages={253–256} }
 @article{matsuura_himuro_yokoi_yamamoto_vargo_keller_2010, title={Identification of a pheromone regulating caste differentiation in termites}, volume={107}, ISSN={["0027-8424"]}, DOI={10.1073/pnas.1004675107}, abstractNote={The hallmark of social insects is their caste system: reproduction is primarily monopolized by queens, whereas workers specialize in the other tasks required for colony growth and survival. Pheromones produced by reining queens have long been believed to be the prime factor inhibiting the differentiation of new reproductive individuals. However, there has been very little progress in the chemical identification of such inhibitory pheromones. Here we report the identification of a volatile inhibitory pheromone produced by female neotenics (secondary queens) that acts directly on target individuals to suppress the differentiation of new female neotenics and identify n-butyl-n-butyrate and 2-methyl-1-butanol as the active components of the inhibitory pheromone. An artificial pheromone blend consisting of these two compounds had a strong inhibitory effect similar to live neotenics. Surprisingly, the same two volatiles are also emitted by eggs, playing a role both as an attractant to workers and an inhibitor of reproductive differentiation. This dual production of an inhibitory pheromone by female reproductives and eggs probably reflects the recruitment of an attractant pheromone as an inhibitory pheromone and may provide a mechanism ensuring honest signaling of reproductive status with a tight coupling between fertility and inhibitory power. Identification of a volatile pheromone regulating caste differentiation in a termite provides insights into the functioning of social insect colonies and opens important avenues for elucidating the developmental pathways leading to reproductive and nonreproductive castes.}, number={29}, journal={PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA}, author={Matsuura, Kenji and Himuro, Chihiro and Yokoi, Tomoyuki and Yamamoto, Yuuka and Vargo, Edward L. and Keller, Laurent}, year={2010}, month={Jul}, pages={12963–12968} }
 @article{menke_booth_dunn_schal_vargo_silverman_2010, title={Is It Easy to Be Urban? Convergent Success in Urban Habitats among Lineages of a Widespread Native Ant}, volume={5}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0009194}, DOI={10.1371/journal.pone.0009194}, abstractNote={The most rapidly expanding habitat globally is the urban habitat, yet the origin and life histories of the populations of native species that inhabit this habitat remain poorly understood. We use DNA barcoding of the COI gene in the widespread native pest ant Tapinoma sessile to test two hypotheses regarding the origin of urban populations and traits associated with their success. First, we determine if urban samples of T. sessile have a single origin from natural populations by looking at patterns of haplotype clustering from across their range. Second, we examine whether polygynous colony structure – a trait associated with invasion success – is correlated with urban environments, by studying the lineage dependence of colony structure. Our phylogenetic analysis of 49 samples identified four well supported geographic clades. Within clades, Kimura-2 parameter pairwise genetic distances revealed <2.3% variation; however, between clade genetic distances were 7.5–10.0%, suggesting the possibility of the presence of cryptic species. Our results indicate that T. sessile has successfully colonized urban environments multiple times. Additionally, polygynous colony structure is a highly plastic trait across habitat, clade, and haplotype. In short, T. sessile has colonized urban habitats repeatedly and appears to do so using life history strategies already present in more natural populations. Whether similar results hold for other species found in urban habitats has scarcely begun to be considered.}, number={2}, journal={PLoS ONE}, publisher={Public Library of Science (PLoS)}, author={Menke, Sean B. and Booth, Warren and Dunn, Robert R. and Schal, Coby and Vargo, Edward L. and Silverman, Jules}, editor={Moreau, Corrie S.Editor}, year={2010}, month={Feb}, pages={e9194} }
 @article{tomalski_leimkuehler_schal_vargo_2010, title={Metabolism of Imidacloprid in Workers of <I>Reticulitermes flavipes</I> (Isoptera: Rhinotermitidae)}, volume={103}, ISSN={0013-8746 0013-8746}, url={http://dx.doi.org/10.1603/008.103.0111}, DOI={10.1603/008.103.0111}, abstractNote={Abstract
               The chloro-nicotinyl insecticide imidacloprid is used extensively as a soil treatment against subterranean termites. We conducted the first study of the metabolic fate of imidacloprid in termites, by exposing workers of the eastern subterranean termite, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae) to radiolabeled imidacloprid through topical application and ingestion. Several days after topical application, we detected up to 11 radiolabeled compounds. The parent compound, IMI, and the following six metabolites were identified by liquid chromatography/mass spectrometry: olefin-imidacloprid (major metabolite), 4/5-OH imidacloprid, 4,5-di-OH imidacloprid, des-nitro olefin imidacloprid, des-nitro imidacloprid, and a glucuronide conjugate of des-nitro imidacloprid (des-nitro IMI-glu). Over time, detoxification of imidacloprid proceeded from less polar to more polar compounds, with des-nitro IMI-glu seeming to be the ultimate, major end product in surviving termites. Degradation of imidacloprid was limited to internal tissues of the termite. Workers fed wood treated with imidacloprid or provided with a treated substrate (sand) had metabolitic profiles similar to topically treated termites. Termites fed imidacloprid or exposed to it in soil excreted detectable amounts of all of the identified metabolites. Finally, we determined that imidacloprid metabolites were less toxic to termites than imidacloprid itself. Only the olefin-imidacloprid and 5-OH imidacloprid caused morbidity in termites exposed to sand treated with these compounds, but at concentrations ≈10–20-fold higher than the parent imidacloprid. Our results shed light on the metabolic pathway used by termites to detoxify imidacloprid and show how metabolism plays a key role in determining the availability of the active ingredient and its various metabolites for transfer among workers within the colony.}, number={1}, journal={Annals of the Entomological Society of America}, publisher={Oxford University Press (OUP)}, author={Tomalski, Michael and Leimkuehler, William and Schal, Coby and Vargo, Edward L.}, year={2010}, month={Jan}, pages={84–95} }
 @article{booth_santangelo_vargo_mukha_schal_2011, title={Population Genetic Structure in German Cockroaches (Blattella Germanica): Differentiated Islands in an Agricultural Landscape}, volume={102}, ISSN={0022-1503 1465-7333}, url={http://dx.doi.org/10.1093/jhered/esq108}, DOI={10.1093/jhered/esq108}, abstractNote={Although a number of species live syanthropically with humans, few rely entirely on humans for their survival and distribution. Unlike other cosmopolitan human commensals, the German cockroach (Blattella germanica), an insect of both public and livestock health concern, is considered incapable of dispersal outside human dwellings. Patterns of genetic association are therefore constrained and may not be associated with distance. Analogies with other human-commensal species are therefore impossible to draw with any degree of accuracy. In the past 2 decades, B. germanica has become a prominent pest within the US swine production system. Swine production is mainly carried out through contracted producers, each associated with a management company. It has been hypothesized that cockroach populations will be genetically structured based on association to a specific management company. Here, we tested this hypothesis using microsatellite genotypes (8 polymorphic loci) from 626 individual cockroaches collected from 22 farms in southeastern North Carolina representing 3 management companies. Significant genetic differentiation was detected (F(ST) = 0.171), most of which was partitioned among the 22 farms rather than the 3 management groups. All pair-wise population comparisons yielded F(ST) values significantly greater than zero. Our results reveal that structure does not correspond to management company of origin, but instead it may be regional and influenced strongly by the unintentional movement of cockroaches by farm workers.}, number={2}, journal={Journal of Heredity}, publisher={Oxford University Press (OUP)}, author={Booth, W. and Santangelo, R. G. and Vargo, E. L. and Mukha, D. V. and Schal, C.}, year={2011}, month={Mar}, pages={175–183} }
 @article{crissman_booth_santangelo_mukha_vargo_schal_2010, title={Population genetic structure of the German cockroach (Blattodea: Blattellidae) in apartment buildings}, volume={47}, DOI={10.1603/me09036}, abstractNote={The German cockroach, Blattella germanica (L.) (Blattodea: Blattellidae), is a major residential pest with the potential to vector various pathogens and produce and disseminate household allergens. Understanding population genetic structure and differentiation of this important pest is critical to efforts to eradicate infestations, yet little is known in this regard. Using highly polymorphic microsatellite markers, we investigated patterns of genetic diversity and differentiation within and among 18 apartments from six apartment complexes located in Raleigh, NC. No departure from panmixia was found between rooms within apartments, indicating that active dispersal resulting in gene flow may occur among rooms within apartment units. Alternatively, aggregations within apartments may exist in relative isolation under a metapopulation framework, derived from a recent, common source. Thus, in the event of population control practices leading to incomplete cockroach eradication within an apartment, recolonization of shelters and rooms is likely to occur from a genetically similar aggregation. A pattern of isolation-by-distance across the six apartment complexes indicated that dispersal was more common within complexes than among them, and F statistics suggested greater genetic similarity between apartments in a single building than between separate buildings of an apartment complex. Similarly, neighbor-joining tree and Bayesian clustering analyses were able to cluster only those apartments that were within a single building, indicating higher dispersal with associated gene flow within buildings than between them. The lack of any broader connectivity, as indicated by significant FST and G-tests suggests that human-mediated dispersal of B. germanica between buildings of an apartment complex or between complexes occurs infrequently enough to have negligible effects on gene flow.}, number={4}, journal={Journal of Medical Entomology}, author={Crissman, J. R. and Booth, W. and Santangelo, R. G. and Mukha, D. V. and Vargo, E. L. and Schal, Coby}, year={2010}, pages={553–564} }
 @article{haverty_tabuchi_vargo_cox_nelson_lewis_2010, title={Response of Reticulitermes hesperus (Isoptera: Rhinotermitidae) Colonies to Baiting With Lufenuron in Northern California}, volume={103}, ISSN={["1938-291X"]}, DOI={10.1603/ec09088}, abstractNote={ABSTRACT The objective of this study was to evaluate lufenuron termite bait (1,500 ppm) for the elimination of colonies of Reticulitermes hesperus Banks (Isoptera: Rhinotermitidae). Dispersion of colonies in six baited and six unbaited sites near Placerville, CA, was determined by genetic (microsatellite) analyses. Twenty-one colonies of R. hesperus inhabited the six baited sites and eight colonies of R. hesperus occurred in the six unbaited sites. Five criteria provided a cause-and-effect link between the deployment of lufenuron termite bait and elimination of baited colonies: 1) association of foragers, as members of the same colony, in the independent monitoring stations and bait stations; 2) quantity of bait consumed; 3) abnormal physical appearance of foragers in bait stations; 4) disappearance of foragers from, and cessation of feeding in, independent monitoring stations visited by baited colonies; and 5) presence of foragers from, and continuation of feeding in, independent monitors visited by unbaited colonies. Baited colonies were devoid of foraging termites within a mean of 70.6 d (range, 37–93 d) of bait deployment. Colonies consumed a mean of 8.0 g of bait (range, 2.2–16.0 g). Wood consumption by baited and unbaited colonies was not significantly different during the 2 mo before baiting, 281.4 versus 590.5 mg/d per colony, respectively, nor during the 3 mo immediately after baiting, 112.5 versus 436.8 mg/d per colony, respectively. However, from 10 to 16 mo after baiting, wood consumption by baited colonies essentially ceased and was significantly less than the unbaited colonies, 7.9 versus 470.1 mg/d per colony, respectively.}, number={3}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Haverty, Michael I. and Tabuchi, Robin L. and Vargo, Edward L. and Cox, David L. and Nelson, Lori J. and Lewis, Vernard R.}, year={2010}, month={Jun}, pages={770–780} }
 @article{matsuura_vargo_kawatsu_labadie_nakano_yashiro_tsuji_2009, title={Queen Succession Through Asexual Reproduction in Termites}, volume={323}, ISSN={["0036-8075"]}, DOI={10.1126/science.1169702}, abstractNote={The evolution and maintenance of sexual reproduction may involve important tradeoffs because asexual reproduction can double an individual's contribution to the gene pool but reduces diversity. Moreover, in social insects the maintenance of genetic diversity among workers may be important for colony growth and survival. We identified a previously unknown termite breeding system in which both parthenogenesis and sexual reproduction are conditionally used. Queens produce their replacements asexually but use normal sexual reproduction to produce other colony members. These findings show how eusociality can lead to extraordinary reproductive systems and provide important insights into the advantages and disadvantages of sex.}, number={5922}, journal={SCIENCE}, author={Matsuura, Kenji and Vargo, Edward L. and Kawatsu, Kazutaka and Labadie, Paul E. and Nakano, Hiroko and Yashiro, Toshihisa and Tsuji, Kazuki}, year={2009}, month={Mar}, pages={1687–1687} }
 @article{brent_traniello_varco_2008, title={Benefits and costs of secondary polygyny in the dampwood termite Zootermopsis angusticollis}, volume={37}, ISSN={["1938-2936"]}, DOI={10.1603/0046-225X(2008)37[883:BACOSP]2.0.CO;2}, abstractNote={Abstract Newly molted female neotenic reproductives of the dampwood termite Zootermopsis angusticollis Hagen were allowed to mature in the presence of a neotenic male, a fixed number of larval helpers, and varying numbers of sibling neotenic queens to assess the impact of secondary polygyny to the individual and colony. Under monogyne conditions, neotenics developed more ovarioles per ovary and had higher individual fecundities after 60 d compared with females under polygyne conditions. Queens in groups of three females were able to gain more body mass than those in groups of five. Although the division of resources provided by helpers reduced individual female development and fecundity under polygyne conditions, it resulted in an overall increase in colony fecundity. In addition, neotenic females in polygynous colonies did not differ significantly in reproductive competence. There was no evidence that neotenics were attacked or injured by other reproductives or larval helpers, suggesting little if any reproductive competition among sibling queens. The physiological responses of neotenics to the increasing queen/worker ratio may have the benefit of enhancing the colony growth at the cost of the fecundity of individual queens.}, number={4}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Brent, Colin S. and Traniello, James F. A. and Varco, Edward I.}, year={2008}, month={Aug}, pages={883–888} }
 @article{vargo_husseneder_2009, title={Biology of Subterranean Termites: Insights from Molecular Studies of Reticulitermes and Coptotermes}, volume={54}, ISSN={["1545-4487"]}, DOI={10.1146/annurev.ento.54.110807.090443}, abstractNote={Molecular genetic techniques have made contributions to studies on subterranean termites at all levels of biological organization. Most of this work has focused on Reticulitermes and Coptotermes, two ecologically and economically important genera. DNA sequence data have significantly improved our understanding of the systematics and taxonomy of these genera. Techniques of molecular biology have provided important new insights into the process of caste differentiation. Population genetic markers, primarily microsatellites, have furthered our understanding of the life history, population biology, community ecology, and invasion biology of subterranean termites. Recent results on the behavioral ecology of subterranean termites reveal a picture different from long-held views, especially those concerning colony breeding structures and foraging ranges. As additional molecular tools and genomic resources become available, and as more subterranean termite researchers incorporate molecular techniques into their approaches, we can expect accelerating advances in all aspects of the biology of this group.}, journal={ANNUAL REVIEW OF ENTOMOLOGY}, author={Vargo, Edward L. and Husseneder, Claudia}, year={2009}, pages={379–403} }
 @article{pfannenstiel_booth_vargo_schal_2008, title={Blattella asahinai (Dictyoptera : Blattellidae): A new predator of lepidopteran eggs in South Texas soybean}, volume={101}, ISSN={["0013-8746"]}, DOI={10.1603/0013-8746(2008)101[763:BADBAN]2.0.CO;2}, abstractNote={Abstract Large numbers of a cockroach that resembled the German cockroach, Blattella germanica (L.), were observed during winter 2005–2006 in home turf settings in Weslaco, TX, 11 km from the U.S. border with northeastern Mexico. In June and July 2006, this cockroach was observed at night on the foliage of soybean, Glycine max (L.) Merr., in numbers often exceeding 50 per m row. Because of its similarity to B. germanica, but with the characteristic of flying frequently, we suspected that our observations might be of the Asian cockroach, Blattella asahinai Mizukubo. Using a combination of morphological characters, cuticular hydrocarbons, and sequences of the mitochondrial cytochrome oxidase II gene, we definitively identified this cockroach as B. asahinai. B. asahinai was frequently observed feeding on sentinel eggs of Helicoverpa zea (Boddie) and Spodoptera exigua (Hübner). This cockroach was the dominant egg predator in soybean during 2006, making up 36.4% of all predators observed feeding on eggs. B. asahinai was only observed occupying the soybean canopy nocturnally, and it made up 53.7% of predators observed feeding at night. We speculate that B. asahinai may serve as an important beneficial insect in soybean and other crops.}, number={4}, journal={ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA}, author={Pfannenstiel, Robert S. and Booth, Warren and Vargo, Edward L. and Schal, Coby}, year={2008}, month={Jul}, pages={763–768} }
 @article{booth_youngsteadt_schal_vargo_2009, title={Characterization of 8 polymorphic microsatellite loci in the neotropical ant-garden ant, Camponotus femoratus (Fabricius)}, volume={10}, ISSN={["1572-9737"]}, DOI={10.1007/s10592-008-9705-z}, number={5}, journal={CONSERVATION GENETICS}, author={Booth, Warren and Youngsteadt, Elsa and Schal, Coby and Vargo, Edward L.}, year={2009}, month={Oct}, pages={1401–1403} }
 @article{booth_lewis_taylor_schal_vargo_2008, title={Identification and characterization of 15 polymorphic microsatellite loci in the western drywood termite, Incisitermes minor (Hagen)}, volume={8}, ISSN={["1755-098X"]}, DOI={10.1111/j.1755-0998.2008.02169.x}, abstractNote={AbstractDespite recognition of the western drywood termite, Incisitermes minor (Hagen), as one of the most economically important and destructive termite species in the USA, both its population and colony breeding structure genetically remain unclear. Here, we present primer sequences and initial characterization for 15 polymorphic microsatellite loci. In a sample of 30 individuals, representing six geographically distinct locations collected in California, USA, three to 15 alleles were detected segregating per locus. Within a single population observed heterozygosity ranged from 0.050 to 0.866.}, number={5}, journal={MOLECULAR ECOLOGY RESOURCES}, author={Booth, W. and Lewis, V. R. and Taylor, R. L. and Schal, C. and Vargo, E. L.}, year={2008}, month={Sep}, pages={1102–1104} }
 @article{booth_youngsteadt_schal_vargo_2009, title={Polymorphic microsatellite loci for the ant-garden ant, Crematogaster levior (Forel)}, volume={10}, ISSN={["1572-9737"]}, DOI={10.1007/s10592-008-9597-y}, abstractNote={Throughout Amazonia, the ant Crematogaster levior is known for its participation in a complex ant-garden mutualism with the ant Camponotus femoratus and several species of epiphytic plants for which it plays an important role in seed viability. We isolated nine polymorphic microsatellite loci for C. levior from a genomic library enriched for di-, tri-, and tetra-nucleotide repeats. Two to 14 alleles were detected per locus, with levels of observed heterozygosity ranging from 0.103 to 0.785.}, number={3}, journal={CONSERVATION GENETICS}, author={Booth, Warren and Youngsteadt, Elsa and Schal, Coby and Vargo, Edward L.}, year={2009}, month={Jun}, pages={639–641} }
 @article{parman_vargo_2008, title={Population density, species abundance, and breeding structure of subterranean termite colonies in and around infested houses in central North Carolina}, volume={101}, ISSN={["0022-0493"]}, DOI={10.1603/0022-0493(2008)101[1349:PDSAAB]2.0.CO;2}, abstractNote={Abstract Pressure from subterranean termites is known to vary geographically across the United States, but there are few quantitative studies concerning the threat of structural infestation for any geographic region. We assessed the number and locations of termite colonies present on 20 infested residential properties in central North Carolina, where subterranean termite pressure is considered to be heavy. This was achieved by using microsatellite markers to determine colony identity of termites collected over 6–14 mo from mud tubes in structures, below-ground monitors, and wood debris in the yard. In total, we identified 188 distinct colonies and determined their breeding structures. Reticulitermes flavipes (Kollar) was by far the most common species, accounting for nearly 90% of all colonies; the remaining colonies belonged to Reticulitermes hageni Banks and Reticulitermes virginicus (Banks). In four cases, there were two colonies infesting a structure simultaneously; in all other cases only a single colony was detected in the structure. Colony densities were high, averaging 62 colonies per ha (25 per acre) with a maximum of 185 colonies per ha (75 colonies per acre). Foraging ranges of R. flavipes and R. hageni colonies were generally small (<30 linear m), and most colonies were headed by a single pair of monogamous reproductives with nearly all the remaining colonies headed by relatively few inbreeding descendants of the original monogamous pair. These results provide the most detailed picture to date of the number, distribution, and colony characteristics of subterranean termite colonies located in and around residential structures.}, number={4}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Parman, Vincent and Vargo, Edward L.}, year={2008}, month={Aug}, pages={1349–1359} }
 @article{deheer_vargo_2008, title={Strong mitochondrial DNA similarity but low relatedness at microsatellite loci among families within fused colonies of the termite Reticulitermes flavipes}, volume={55}, ISSN={["1420-9098"]}, DOI={10.1007/s00040-008-0999-0}, number={2}, journal={INSECTES SOCIAUX}, author={DeHeer, C. J. and Vargo, E. L.}, year={2008}, month={May}, pages={190–199} }
 @article{husseneder_powell_grace_vargo_matsuura_2008, title={Worker size in the Formosan subterranean termite in relation to colony breeding structure as inferred from molecular markers}, volume={37}, ISSN={["1938-2936"]}, DOI={10.1603/0046-225X(2008)37[400:WSITFS]2.0.CO;2}, abstractNote={Abstract The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an invasive species that originated in China and has been introduced to Hawaii and the U.S. mainland. Colonies are headed either by a pair of reproductives (simple families) or by varying numbers of inbreeding reproductives (extended families), and therefore have variable degrees of inbreeding. Worker size also varies among colonies of Formosan termites. We tested whether variation in worker size can be explained by the breeding system. Workers were collected from colonies from three geographically separated populations (China, Hawaii, and Louisiana), and body weight and head size were measured. Microsatellite genotyping was used to establish whether colonies were simple or extended families and to determine the heterozygosity of workers and their degree of inbreeding relative to their colony (FIC, sensitive to the number of reproductives). All Chinese colonies contained multiple inbreeding neotenics. In Hawaii, 37% of the colonies were simple families and 63% were extended families, both having considerable degrees of inbreeding. In Louisiana, 57% of the colonies were simple families, which were mostly headed by unrelated pairs, and 43% were extended families. In simple families, size and body weight of workers were not associated with FIC or heterozygosity. In extended families of two populations, both size parameters were negatively correlated with FIC; however, heterozygosity was not associated with worker size in any of the populations. This suggests that the number of reproductives within colonies has a stronger influence on worker size than the individuals’ genetic diversity in Formosan subterranean termite colonies.}, number={2}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Husseneder, Claudia and Powell, Janine E. and Grace, J. Kenneth and Vargo, Edward L. and Matsuura, Kenji}, year={2008}, month={Apr}, pages={400–408} }
 @article{mukha_kagramanova_lazebnaya_lazebnyi_vargo_schal_2007, title={Intraspecific variation and population structure of the German cockroach, Blattella germanica, revealed with RFLP analysis of the non-transcribed spacer region of ribosomal DNA}, volume={21}, ISSN={["1365-2915"]}, DOI={10.1111/j.1365-2915.2007.00670.x}, abstractNote={AbstractLittle information is available on genetic variation within and between populations of pest cockroaches. In this study, intraspecificHindIII polymorphism was investigated in the German cockroach,Blattella germanica(Linnaeus) (Dictyoptera, Blattaria: Blattellidae), using restriction fragment length polymorphisms (RFLP) of the non‐transcribed spacer (NTS) region of ribosomal DNA (rDNA). Individual male insects were collected from infestations at three different pig farms. Each population was characterized byHindIII restriction fragment frequencies and haplotype (a particular X‐chromosome pattern) frequencies. The inheritance of the X‐chromosomeHindIII rDNA patterns over 12 generations (3 years) follows Mendelian patterns, and the stability of this polymorphic marker indicates infrequent genetic recombination of variable sites. Although pairwise genetic distance measures were uncorrelated with geographical distance, the pattern of genetic differentiation of the three cockroach populations suggests that human‐mediated transport of cockroaches is an important force in shaping the population genetic structure of cockroach infestations, at least at the regional scale of 10–100 km. Sequence variation in the ribosomal NTS is a useful marker, and RFLP of rDNA is a simple, robust and reproducible technique for differentiating recently diverged cockroach populations.}, number={2}, journal={MEDICAL AND VETERINARY ENTOMOLOGY}, author={Mukha, D. V. and Kagramanova, A. S. and Lazebnaya, I. V. and Lazebnyi, O. E. and Vargo, E. L. and Schal, C.}, year={2007}, month={Jun}, pages={132–140} }
 @article{vargo_carlson_2006, title={Comparative study of breeding systems of sympatric subterranean termites (Reticulitermes flavipes and R-hageni) in Central North Carolina using two classes of molecular genetic markers}, volume={35}, ISSN={["0046-225X"]}, DOI={10.1603/0046-225X-35.1.173}, abstractNote={Abstract We used microsatellite and mtDNA markers to compare colony and population genetics of two sympatric species of subterranean termites, Reticulitermes flavipes (Kollar) (n = 25 colonies) and R. hageni Banks (n = 16 colonies), in two sites located 27 km apart in the Piedmont of central North Carolina. Colony breeding structure was inferred by examination of microsatellite genotypes of workers within colonies and by estimates of nestmate relatedness and hierarchical F-statistics. Similar to previous results on this species, nearly one-half of the R. flavipes colonies were simple families mainly headed by outbred primary (alate-derived) reproductives, about one-half were comprised of extended (inbred) families inferred to be headed by low numbers of neotenics (non alate-derived secondary reproductives) descended from the original primary pair, and two colonies contained the offspring of multiple reproductives. About two-thirds of the R. hageni colonies were comprised of simple families largely headed by related reproductives, and about one-third consisted of extended families headed by low numbers of neotenics. R. hageni differed from R. flavipes in having significant isolation by distance at one site as well as significant differentiation between sites at both the microsatellite and mtDNA markers. We conclude that dispersal in R. hageni is more limited resulting in higher levels of inbreeding within colonies and greater degrees of population genetic structure at small and large spatial scales than in sympatric populations of R. flavipes. These results indicate that closely related species of subterranean termites occurring in the same habitat can differ in their breeding systems with important consequences for higher level genetic structure.}, number={1}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Vargo, EL and Carlson, JR}, year={2006}, month={Feb}, pages={173–187} }
 @article{brent_schal_vargo_2007, title={Endocrine effects of social stimuli on maturing queens of the dampwood termite Zootermopsis angusticollis}, volume={32}, ISSN={["1365-3032"]}, DOI={10.1111/j.1365-3032.2006.00536.x}, abstractNote={AbstractThe reproductive physiology of social insects is often highly responsive to social stimuli from nestmates, but the mechanisms underlying this sensitivity are usually poorly understood. The effect of varied social conditions on the endocrinology and ovarian maturation in maturing female primary reproductives of the dampwood termiteZootermopsis angusticollisHagen is studied to better understand their developmental responses to conspecifics. Newly dealate queens are paired with a reproductive male, with another maturing female, or are allowed to mature in isolation. Developmental responses are tracked by monitoring rates of juvenile hormone (JH) production by corpora allatain vitro, haemolymph ecdysteroids titres and ovarian development after 5, 10, 15 and 30 days of maturation. Significant declines in rates of JH production rates are observed by days 5, 10 and 30, respectively, for females paired with males, left to mature in isolation or paired with a female. Ecdysteroid titres increase by day 5 and stay elevated in females nesting with males. By contrast, for CA from females that are isolated or paired with another female, the titres decline and stay low until at least day 15, but increase significantly by day 30. These hormonal differences correspond to differential rates of physiological maturation, with more rapid ovarian development occurring in females paired with a male, than in those nesting alone or with another female. The results suggest that JH and ecdysteroids modulate the ovarian response of alates to stimuli from nestmates during this period of maturation, and that JH and ecdysteroid titres may be regulated independently during this period of development.}, number={1}, journal={PHYSIOLOGICAL ENTOMOLOGY}, author={Brent, Colin S. and Schal, Coby and Vargo, Edward L.}, year={2007}, month={Mar}, pages={26–33} }
 @article{vargo_husseneder_woodson_waldvogel_grace_2006, title={Genetic analysis of colony and population structure of three introduced populations of the Formosan subterranean termite (Isoptera : Rhinotermitidae) in the Continental United States}, volume={35}, ISSN={["0046-225X"]}, DOI={10.1603/0046-225X-35.1.151}, abstractNote={Abstract The Formosan subterranean termite, Coptotermes formosanus Shiraki, is a major invasive pest species in many parts of the world. We compared the colony breeding system and population genetic structure in three introduced populations in the continental United States: Charleston, SC; City Park, New Orleans, LA; and Rutherford County, NC. Based on worker genotypes at 12 microsatellite loci, we found that colonies were mainly genetically distinct entities consisting of either simple families headed by monogamous pairs of reproductives or extended families containing multiple neotenic (replacement) reproductives descended from simple families. Populations varied from 48% simple families in Charleston to 82% simple families in City Park. Extended family colonies in all three populations were likely headed by <10 neotenic reproductives. There was no significant isolation by distance in any of the populations, suggesting that colonies reproduce by relatively long-range mating flights and/or human-mediated dispersal within each population. The Charleston population showed evidence of a recent genetic bottleneck and most likely was founded by very few colonies. Cluster analysis indicated that the Charleston and City Park populations are quite genetically distant from each other and most likely originated from different source populations. The more recently introduced Rutherford County population was genetically most similar to City Park. These findings, together with results from other infested sites, indicate considerable variation in the genetic structure and breeding system of introduced populations of this species, making it unlikely that there is a simple genetic or behavioral explanation for the success of C. formosanus as an invasive species.}, number={1}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Vargo, EL and Husseneder, C and Woodson, D and Waldvogel, MG and Grace, JK}, year={2006}, month={Feb}, pages={151–166} }
 @article{brent_peeters_dietemann_crewe_vargo_2006, title={Hormonal correlates of reproductive status in the queenless ponerine ant, Streblognathus peetersi (vol 193, pg 315, 2006)}, volume={192}, ISSN={["0340-7594"]}, DOI={10.1007/s00359-006-0107-8}, number={3}, journal={JOURNAL OF COMPARATIVE PHYSIOLOGY A-NEUROETHOLOGY SENSORY NEURAL AND BEHAVIORAL PHYSIOLOGY}, author={Brent, C and Peeters, C and Dietemann, V and Crewe, R and Vargo, E}, year={2006}, month={Mar}, pages={339–339} }
 @article{booth_bogdanowicz_prodohl_harrison_schal_vargo_2007, title={Identification and characterization of 10 polymorphic microsatellite loci in the German cockroach, Blattella germanica}, volume={7}, ISSN={["1471-8278"]}, DOI={10.1111/j.1471-8286.2006.01663.x}, abstractNote={AbstractPrimer sequences and initial characterization are presented for 10 microsatellite loci isolated from the German cockroach, Blattella germanica. In a sample of 30 individuals from a single population sample, all loci were polymorphic with two to 12 alleles segregating per locus and levels of observed heterozygosity ranging from 0.27 to 0.92. One locus showed a deficit of heterozygotes. Experimental conditions are described for polymerase chain reaction multiplexing, which enables the genotyping of eight loci in three electrophoretic runs consisting of one set of three and two sets of two markers. Seven primer sets cross‐amplify in the related Blattella asahinai.}, number={4}, journal={MOLECULAR ECOLOGY NOTES}, author={Booth, W. and Bogdanowicz, S. M. and Prodohl, P. A. and Harrison, R. G. and Schal, C. and Vargo, E. L.}, year={2007}, month={Jul}, pages={648–650} }
 @article{calleri_reid_rosengaus_vargo_traniello_2006, title={Inbreeding and disease resistance in a social insect: effects of heterozygosity on immnnocompetence in the termite Zootermopsis angusticollis}, volume={273}, ISSN={["1471-2954"]}, DOI={10.1098/rspb.2006.3622}, abstractNote={
            Recent research has shown that low genetic variation in individuals can increase susceptibility to infection and group living may exacerbate pathogen transmission. In the eusocial diploid termites, cycles of outbreeding and inbreeding characterizing basal species can reduce genetic variation within nestmates during the life of a colony, but the relationship of genetic heterogeneity to disease resistance is poorly understood. Here we show that, one generation of inbreeding differentially affects the survivorship of isolated and grouped termites (
            Zootermopsis angusticollis)
            depending on the nature of immune challenge and treatment. Inbred and outbred isolated and grouped termites inoculated with a bacterial pathogen, exposed to a low dose of fungal pathogen or challenged with an implanted nylon monofilament had similar levels of immune defence. However, inbred grouped termites exposed to a relatively high concentration of fungal conidia had significantly greater mortality than outbred grouped termites. Inbred termites also had significantly higher cuticular microbial loads, presumably due to less effective grooming by nestmates. Genetic analyses showed that inbreeding significantly reduced heterozygosity and allelic diversity. Decreased heterozygosity thus appeared to increase disease susceptibility by affecting social behaviour or some other group-level process influencing infection control rather than affecting individual immune physiology.
          }, number={1601}, journal={PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES}, author={Calleri, Daniel V., II and Reid, Ellen McGrail and Rosengaus, Rebeca B. and Vargo, Edward L. and Traniello, James F. A.}, year={2006}, month={Oct}, pages={2633–2640} }
 @article{vargo_juba_deheer_2006, title={Relative abundance and comparative breeding structure of subterranean termite colonies (Reticulitermes flavipes, Reticulitermes hageni, Reticulitermes virginicus, and Coptotermes formosanus) in a South Carolina lowcountry site as revealed by molecular markers}, volume={99}, ISSN={["0013-8746"]}, DOI={10.1603/0013-8746(2006)99[1101:RAACBS]2.0.CO;2}, abstractNote={Abstract There are several species of subterranean termites in the United States, some of which occur sympatrically over broad geographic regions. However, there is little information on the relative abundance of the different species or the extent to which they differ with respect to colony social and spatial organization. We used microsatellite markers to investigate the relative numbers of colonies, to infer colony breeding structures, and to delineate colony foraging areas in four species of subterranean termites occurring in a state park in Charleston, SC. The two most abundant species, Reticulitermes hageni Banks and Reticulitermes flavipes (Kollar), which together accounted for 80% of the 49 colonies sampled, had fairly localized foraging ranges of <30 m across. In contrast, Reticulitermes virginicus (Banks) and the Formosan subterranean termite, Coptotermes formosanus Shiraki, had far fewer colonies, but these colonies were more expansive, spanning distances >100 linear m. Colonies of all species were primarily simple families each headed by a single monogamous pair of reproductives. Generally, the remaining colonies of each species were consistent with being extended families, i.e., headed by multiple neotenic reproductives descended from simple families. Only in R. flavipes was a mixed family colony detected, with workers from two distinct families occurring together. These results from molecular markers reveal how the various species in a relatively diverse subterranean termite community can vary in abundance, size of colony foraging area and breeding structure, thereby setting the stage for subsequent studies to identify the factors shaping these communities.}, number={6}, journal={ANNALS OF THE ENTOMOLOGICAL SOCIETY OF AMERICA}, author={Vargo, Edward L. and Juba, Thomas R. and Deheer, Christopher J.}, year={2006}, month={Nov}, pages={1101–1109} }
 @article{deheer_vargo_2006, title={An indirect test of inbreeding depression in the termites Reticulitermes flavipes and Reticulitermes virginicus}, volume={59}, ISSN={["1432-0762"]}, DOI={10.1007/s00265-005-0105-9}, number={6}, journal={BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY}, author={DeHeer, CJ and Vargo, EL}, year={2006}, month={Apr}, pages={753–761} }
 @article{husseneder_messenger_su_grace_vargo_2005, title={Colony social organization and population genetic structure of an introduced population of Formosan subterranean termite from New Orleans, Louisiana}, volume={98}, ISSN={["1938-291X"]}, DOI={10.1603/0022-0493-98.5.1421}, abstractNote={Abstract The Formosan subterranean termite, Coptotermes formosanus Shiraki, is an invasive species in many parts of the world, including the U.S. mainland. The reasons for its invasive success may have to do with the flexible social and spatial organization of colonies. We investigated the population and breeding structure of 14 C. formosanus colonies in Louis Armstrong Park, New Orleans, LA. This population has been the focus of extensive study for many years, providing the opportunity to relate aspects of colony breeding structure to previous findings on colony characteristics such as body weight and number of workers, wood consumption, and intercolony aggression. Eight colonies were headed by a single pair of outbred reproductives (simple families), whereas six colonies were headed by low numbers of multiple kings and/or queens that were likely the neotenic descendants of the original colony (extended families). Within the foraging area of one large extended family colony, we found genetic differentiation among different collection sites, suggesting the presence of separate reproductive centers. No significant difference between simple family colonies and extended family colonies was found in worker body weight, soldier body weight, foraging area, population size, or wood consumption. However, level of inbreeding within colonies was negatively correlated with worker body weight and positively correlated with wood consumption. Also, genetic distance between colonies was positively correlated with aggression levels, suggesting a genetic basis to nestmate discrimination cues in this termite population. No obvious trait associated with colony reproductive structure was found that could account for the invasion success of this species.}, number={5}, journal={JOURNAL OF ECONOMIC ENTOMOLOGY}, author={Husseneder, C and Messenger, MT and Su, NY and Grace, JK and Vargo, EL}, year={2005}, month={Oct}, pages={1421–1434} }
 @article{menten_fournier_brent_passera_vargo_aron_2005, title={Dual mechanism of queen influence over sex ratio in the ant Pheidole pallidula}, volume={58}, ISSN={["1432-0762"]}, DOI={10.1007/s00265-005-0964-0}, abstractNote={Social Hymenoptera are general models for the study of parent-offspring conflict over sex ratio, because queens and workers frequently have different reproductive optima. The ant Pheidole pallidula shows a split distribution of sex ratios with most of the colonies producing reproductives of a single sex. Sex ratio specialization is tightly associated with the breeding system, with single-queen (monogynous) colonies producing male-biased brood and multiple-queen (polygynous) colonies female-biased brood. Here, we show that this sex specialization is primarily determined by the queen's influence over colony sex ratio. Queens from monogynous colonies produce a significantly more male-biased primary sex ratio than queens from polygynous colonies. Moreover, queens from monogynous colonies produce a significantly lower proportion of diploid eggs that develop into queens and this is associated with lower rate of juvenile hormone (JH) production compared to queens from polygynous colonies. These results indicate that queens regulate colony sex ratio in two complementary ways: by determining the proportion of female eggs laid and by hormonally biasing the development of female eggs into either a worker or reproductive form. This is the first time that such a dual system of queen influence over colony sex ratio is identified in an ant.}, number={6}, journal={BEHAVIORAL ECOLOGY AND SOCIOBIOLOGY}, author={Menten, L and Fournier, D and Brent, C and Passera, L and Vargo, EL and Aron, S}, year={2005}, month={Oct}, pages={527–533} }
 @article{brent_schal_vargo_2005, title={Endocrine changes in maturing primary queens of Zootermopsis angusticollis}, volume={51}, ISSN={["0022-1910"]}, DOI={10.1016/j.jinsphys.2005.06.009}, abstractNote={Termite queens are highly specialized for reproduction, but little is known about the endocrine mechanisms regulating this ability. We studied changes in the endocrinology and ovarian maturation in primary reproductive females of the dampwood termite Zootermopsis angusticollis following their release from inhibitory stimuli produced by mature queens. Winged alates were removed from their natal nest, manually dewinged, then paired in an isolated nest with a reproductive male. Development was tracked by monitoring ovarian development, in vitro rates of juvenile hormone (JH) production by corpora allata, and hemolymph titers of JH and ecdysteroids. The production rate and titer of JH were positively correlated with each other but negatively correlated with ecdysteroid titer. Four days after disinhibition, JH release and titer decreased while ecdysteroid titer increased. The new levels persisted until day 30, after which JH increased and ecdysteroids decreased. Fully mature queens had the highest rates of JH production, the lowest ecdysteroid titers, and the greatest number of functional ovarioles. The results support the hypothesis that JH plays a dual role in termite queens depending on their stage of development; an elevated JH titer in immature alates may maintain reproductive inhibition, but an elevated JH titer in mature queens may stimulate ovarian activity. The decline in JH production and the elevation in ecdysteroid titer correspond to a period of physiological reorganization and activation. The specific function of ecdysteroids is unknown but they may help to modulate the activity of the corpora allata.}, number={11}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Brent, CS and Schal, C and Vargo, EL}, year={2005}, month={Nov}, pages={1200–1209} }
 @article{dronnet_chapuisat_vargo_lohou_bagneres_2005, title={Genetic analysis of the breeding system of an invasive subterranean termite, Reticulitermes santonensis, in urban and natural habitats}, volume={14}, DOI={10.1111/j.1365-294X.2005.02508.x}, abstractNote={Abstract Reticulitermes santonensis is a subterranean termite that invades urban areas in France and elsewhere where it causes damage to human‐built structures. We investigated the breeding system, colony and population genetic structure, and mode of dispersal of two French populations of R. santonensis. Termite workers were sampled from 43 and 31 collection points, respectively, from a natural population in west–central France (in and around the island of Oléron) and an urban population (Paris). Ten to 20 workers per collection point were genotyped at nine variable microsatellite loci to determine colony identity and to infer colony breeding structure. There was a total of 26 colonies, some of which were spatially expansive, extending up to 320 linear metres. Altogether, the analysis of genotype distribution, F‐statistics and relatedness coefficients suggested that all colonies were extended families headed by numerous neotenics (nonwinged precocious reproductives) probably descended from pairs of primary (winged) reproductives. Isolation by distance among collection points within two large colonies from both populations suggested spatially separated reproductive centres with restricted movement of workers and neotenics. There was a moderate level of genetic differentiation (FST = 0.10) between the Oléron and Paris populations, and the number of alleles was significantly higher in Oléron than in Paris, as expected if the Paris population went through bottlenecks when it was introduced from western France. We hypothesize that the diverse and flexible breeding systems found in subterranean termites pre‐adapt them to invade new or marginal habitats. Considering that R. santonensis may be an introduced population of the North American species R. flavipes, a breeding system consisting primarily of extended family colonies containing many neotenic reproductives may facilitate human‐mediated spread and establishment of R. santonensis in urban areas with harsh climates.}, number={5}, journal={Molecular Ecology}, author={Dronnet, S. and Chapuisat, M. and Vargo, E. L. and Lohou, C. and Bagneres, A. G.}, year={2005}, pages={1311–1320} }
 @article{brent_peeters_dietmann_crewe_vargo_2006, title={Hormonal correlates of reproductive status in the queenless ponerine ant, Streblognathus peetersi}, volume={192}, ISSN={["1432-1351"]}, DOI={10.1007/s00359-005-0065-6}, abstractNote={In colonies of the queenless ant Streblognathus peetersi, dominance interactions produce a reproductive hierarchy in which one individual, the alpha, is capable of producing offspring while her subordinates remain infertile. Based on differences between behaviour and cuticular hydrocarbon profiles, the subordinates can be further divided into high and low ranking workers. Although it had been shown previously that alphas treated with a juvenile hormone analog lose their reproductive status, little was known of the endocrinological basis of dominance in this species. To elucidate the underlying endocrinology of these three ranks, we measured the individual in vitro rate of juvenile hormone (JH) production of excised corpora allata, and the ecdysteroid titer of pooled hemolymph samples. Production of JH was highest in low-ranking workers, intermediate in high rankers, and almost undetectable in alphas. Ecdysteroid titers were low for low rankers, but were more than twice as high for both high rankers and alphas. The results support the hypothesis that JH suppresses ovarian function in these queenless ants, and suggest that ecdysteroids may be responsible for stimulating vitellogenin production. The possible role of these hormones as behavioural modulators is also discussed.}, number={3}, journal={JOURNAL OF COMPARATIVE PHYSIOLOGY A-NEUROETHOLOGY SENSORY NEURAL AND BEHAVIORAL PHYSIOLOGY}, author={Brent, C and Peeters, C and Dietmann, V and Crewe, R and Vargo, E}, year={2006}, month={Mar}, pages={315–320} }
 @article{copren_nelson_vargo_haverty_2005, title={Phylogenetic analyses of mtDNA sequences corroborate taxonomic designations based on cuticular hydrocarbons in subterranean termites}, volume={35}, ISSN={["1095-9513"]}, DOI={10.1016/j.ympev.2005.03.002}, abstractNote={Cuticular hydrocarbons (CHCs) are valuable characters for the analysis of cryptic insect species with few discernible morphological characters. Yet, their use in insect systematics, specifically in subterranean termites in the genus Reticulitermes (Isoptera: Rhinotermitidae), remains controversial. In this paper, we show that taxonomic designations in Reticulitermes from California (USA) suggested in light of differences among CHC phenotypes are corroborated by phylogenetic analyses using mtDNA sequences. Analyses based on CHC phenotypes and supported, in part, by behavioral and ecological differences have suggested the presence of more species than the two currently recognized: R. hesperus Banks and R. tibialis Banks. We analyze a 680 base pair fragment of the mitochondrial DNA cytochrome oxidase (COII) gene from 45 new (21 collection localities) and two previously recorded samples of Reticulitermes from California using parsimony and maximum likelihood methods. Both methods result in trees with highly similar topologies. Bootstrapping indicates support for six clades of Reticulitermes, and corroborates groupings based on cuticular hydrocarbons. One of the clades, R. hesperus, is already recognized in California, while four clades appear to be previously undescribed taxa. Although identification of the final clade is inconclusive, it includes a sample putatively identified as R. tibialis. Therefore, using phylogenetic analyses we corroborate chemical characters used to identify taxa, associate a chemical phenotype with a previously described species, and provide additional support for undescribed taxa of Reticulitermes.}, number={3}, journal={MOLECULAR PHYLOGENETICS AND EVOLUTION}, author={Copren, KA and Nelson, LJ and Vargo, EL and Haverty, MI}, year={2005}, month={Jun}, pages={689–700} }
 @article{deheer_kutnik_vargo_bagneres_2005, title={The breeding system and population structure of the termite Reticulitermes grassei in Southwestern France}, volume={95}, ISSN={["0018-067X"]}, DOI={10.1038/sj.hdy.6800744}, abstractNote={We assessed colony and population structure in three French populations of the termite Reticulitermes grassei using eight polymorphic microsatellite loci. Although most colonies contained the offspring of multiple, highly related replacement reproductives (complex families), some contained the offspring of a single pair of reproductives (simple families), and the proportion of such colonies varied across populations. Populations also showed variability in the numbers of reproductives within complex families; the F-statistics of these families in one population were consistent with having upwards of 100 replacement reproductives, while in another population these colonies contained fewer than 10 pairs of reproductives. Colony boundaries in all populations were well defined, in spite of reports of a widespread breakdown in nestmate recognition and unicolonial populations of R. grassei from these regions in France. A second unexpected finding was a lack of significant isolation by distance among colonies within populations, indicating that colony reproduction by budding was rare or absent. The lack of this form of colony reproduction even within populations where it is expected to be common suggested that the propensity for colony budding may not be as common as suggested by the literature.}, number={5}, journal={HEREDITY}, author={DeHeer, CJ and Kutnik, M and Vargo, EL and Bagneres, AG}, year={2005}, month={Nov}, pages={408–415} }
 @article{fisher_gold_vargo_cognato_2004, title={Behavioral and genetic analysis of colony fusion in Reticulitermes flavipes (Isoptera: Rhinotermitidae)}, volume={44}, number={3}, journal={Sociobiology}, author={Fisher, M. L. and Gold, R. E. and Vargo, E. L. and Cognato, A. I.}, year={2004}, pages={565–576} }
 @article{tomalski_vargo_2004, title={Chain reaction}, volume={72}, ISBN={0031-6121}, number={5}, journal={Pest Control}, author={Tomalski, M. and Vargo, E.}, year={2004}, pages={51} }
 @article{fan_schal_vargo_bagneres_2004, title={Characterization of termite lipophorin and its involvement in hydrocarbon transport}, volume={50}, DOI={10.1016/j.jinphys.2004.04.007}, number={7}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={FAN, YL and Schal, Coby and VARGO, EL and BAGNERES, AG}, year={2004}, pages={609–620} }
 @article{deheer_vargo_2004, title={Colony genetic organization and colony fusion in the termite Reticulitermes flavipes as revealed by foraging patterns over time and space}, volume={13}, DOI={10.1046/j.1365-294X.2003.02065.x}, number={2}, journal={Molecular Ecology}, author={Deheer, C. J. and Vargo, E. L.}, year={2004}, pages={431–441} }
 @article{deheer_vargo_2004, title={Colony genetic organization and colony fusion in the termite Reticulitermes flavipes as revealed by foraging patterns over time and space}, volume={13}, ISSN={["1365-294X"]}, DOI={10.1046/j.1365-294x.2003.2065.x}, abstractNote={AbstractTemporal and spatial analyses are seldom utilized in the study of colony genetic structure, but they are potentially powerful methods which can yield novel insights into the mechanisms underlying variation in breeding systems. Here we present the results of a study which incorporated both of these dimensions in an examination of genetic structure of subterranean termites in the genusReticulitermes (primarilyR. flavipes). Most colonies of this species (70%) were simple families apparently headed by outbred primary reproductives, while most of the remaining (27% of the total) colonies contained low effective numbers of moderately inbred reproductives. Mapping the spatial distribution of colony foraging sites over time revealed that despite the high colony density, the absolute foraging boundaries of mostR. flavipescolonies were persistent and exclusive of other conspecific colonies, which suggests that this species is more territorial than has been implied by laboratory studies of intraspecific aggression. Nevertheless, we found a single colony (3% of all colonies) which contained the offspring of more than two unrelated reproductives. Although other studies have also described subterranean termite colonies with a similarly complex genetic composition, we demonstrate here that such colonies can form under natural conditions via the fusion of whole colonies. This study underscores how repeated sampling from individual colonies over time and space can yield information about colony spatial and genetic structure that cannot be obtained from conventional analyses or sampling methods.}, number={2}, journal={MOLECULAR ECOLOGY}, author={Deheer, CJ and Vargo, EL}, year={2004}, month={Feb}, pages={431–441} }
 @article{dronnet_bagneres_juba_vargo_2004, title={Polymorphic microsatellite loci in the European subterranean termite, Reticulitermes santonensis Feytaud}, volume={4}, ISSN={["1471-8278"]}, DOI={10.1111/j.1471-8286.2004.00600.x}, abstractNote={AbstractWe report on the identification and characterization of two dinucleotide, two trinucleotide and eight tetranucleotide microsatellite DNA loci isolated from the European subterranean termite Reticulitermes santonensis. We tested the loci on 51–92 individuals from 46 colonies from different regions of France. Eleven loci were polymorphic with 2–8 alleles per locus and low observed heterozygosities (0.10–0.48). We also tested the loci on 17–20 individuals from 10 colonies in the closely related North American species R. flavipes and found significantly more alleles (2–9 alleles per locus) and higher observed heterozygosities (0.15–0.80) than in R. santonensis. The lower observed heterozygosities in R. santonensis are consistent with higher levels of inbreeding in these colonies due to the presence of numerous inbred replacement reproductives.}, number={1}, journal={MOLECULAR ECOLOGY NOTES}, author={Dronnet, S and Bagneres, AG and Juba, TR and Vargo, EL}, year={2004}, month={Mar}, pages={127–129} }
 @article{buczkowski_vargo_silverman_2004, title={The diminutive supercolony: the Argentine ants of the southeastern United States}, volume={13}, ISSN={["1365-294X"]}, DOI={10.1111/j.1365-294X.2004.02261.x}, abstractNote={AbstractNative to Argentina and Brazil, the Argentine ant (Linepithema humile) is an invasive species that has become established on six continents and many oceanic islands. In several parts of its introduced range, including the western United States, southern Europe and Chile, the Argentine ant is unicolonial, forming extensive supercolonies. We examined population genetic structure and intercolony aggression in two regions of the introduced range of this species in the United States: California and the southeastern United States. Our results show that the southeastern L. humile population has high genotypic variability and strong intercolony aggression relative to the California population. In the California population, intercolony aggression was absent and 23 alleles were found across seven polymorphic microsatellite loci. However, in the Southeast, aggression between colonies was high and 47 alleles were present across the same seven loci in an equal number of colonies. We suggest that distinctly different colonization patterns for California and the Southeast may be responsible for the striking disparity in the genetic diversity of introduced populations. Southeastern colonies may have descended from multiple, independent introductions from the native range, undergoing a bottleneck at each introduction. In contrast, the California supercolony may have originated from one or more colonies inhabiting the southeastern United States, thus experiencing a double bottleneck. The differences in present‐day distribution patterns between California and the Southeast may be due to the combined effect of two factors: lower winter temperatures in the Southeast and/or competition with another successful and widely distributed ant invader, the fire ant Solenopsis invicta.}, number={8}, journal={MOLECULAR ECOLOGY}, author={Buczkowski, G and Vargo, EL and Silverman, J}, year={2004}, month={Aug}, pages={2235–2242} }
 @article{brent_vargo_2003, title={Changes in juvenile hormone biosynthetic rate and whole body content in maturing virgin queens of Solenopsis invicta}, volume={49}, ISSN={["1879-1611"]}, DOI={10.1016/S0022-1910(03)00166-5}, abstractNote={Studies were conducted on the physiological and hormonal changes following the release of alates from developmentally suppressive pheromones produced by mature queens of the fire ant Solenopsis invicta Buren. Winged virgin queens were removed from the pheromonal signal and placed in colony fragments. The time for dealation, degree of ovarian development, and biosynthesis rate and whole body content of juvenile hormone (JH) were measured. The production rate and content of JH were highly correlated. Dealation and the initiation of oviposition corresponded to peak production of JH. JH production rose sharply following separation from the natal nest, peaking after 3 days. After 8 days of isolation, JH production gradually subsided to levels similar to that found in pre-release queens, but began to increase again after 12 days. Mature queens had highly elevated levels of JH relative to recently dealate females, probably reflecting the increased reproductive capability of these older females. The results support the hypothesis that the pheromone released by functional queens inhibits reproduction in virgin alates by suppressing corpora allata activity and the production of JH.}, number={10}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Brent, CS and Vargo, EL}, year={2003}, month={Oct}, pages={967–974} }
 @article{vargo_husseneder_grace_henderson_ring_2003, title={Colony and population genetic structure of Formosan subterranean termites from Hawaii and Louisiana}, volume={41}, number={1A}, journal={Sociobiology}, author={Vargo, E. L. and Husseneder, C. and Grace, J. K. and Henderson, G. and Ring, D.}, year={2003}, pages={67–69} }
 @article{vargo_husseneder_grace_2003, title={Colony and population genetic structure of the Formosan subterranean termite, Coptotermes formosanus, in Japan}, volume={12}, ISSN={["0962-1083"]}, DOI={10.1046/j.1365-294X.2003.01938.x}, abstractNote={AbstractSubterranean termites have unusual plasticity in their breeding systems. As a result of their cryptic foraging and nesting habits, detailed information on the numbers and types of reproductive individuals in colonies has been difficult to obtain. In this study, we used microsatellite markers to infer the major features of the breeding system of the Formosan subterranean termite, Coptotermes formosanus, in southern Japan, where it is believed to have been introduced from China. A total of 30 colonies was sampled from two islands (Kyushu and Fukue) located 100 km apart. Twenty workers from each colony were genotyped at six microsatellite loci. Analysis of worker genotypes within colonies indicated that 27 colonies (90%) were simple (Mendelian) families. The remaining three colonies, all from Kyushu, were consistent with being extended families having begun as simple families but being currently headed by multiple neotenic (secondary) reproductives descended from the original king and queen. Workers from simple families in both populations were significantly inbred (FIT = 0.10 for Kyushu and 0.46 for Fukue) and highly related to their nestmates (coefficient of relatedness, r = 0.59 for Kyushu and 0.77 for Fukue), suggesting that many simple‐family colonies were headed by closely related reproductives, especially in the Fukue population. This conclusion is supported by the high coefficient of relatedness between nestmate reproductives in simple‐family colonies (r = 0.23 for Kyushu and 0.61 for Fukue) based on genotypes inferred from their worker offspring. There was moderate genetic differentiation (FST = 0.12) between the two populations, suggesting rather restricted gene flow between them. There was no significant isolation by distance among colonies, as might be expected given the limited dispersal of reproductives, presumably because of the frequent movement of colonies by humans. Finally, there was no evidence of a recent bottleneck, a finding possibly consistent with the more than 300‐year history of this species in Japan.}, number={10}, journal={MOLECULAR ECOLOGY}, author={Vargo, EL and Husseneder, C and Grace, JK}, year={2003}, month={Oct}, pages={2599–2608} }
 @article{husseneder_grace_messenger_vargo_su_2003, title={Describing the spatial and social organization of Formosan subterranean termite colonies in Armstrong Park, New Orleans}, volume={41}, number={1A}, journal={Sociobiology}, author={Husseneder, C. and Grace, J. K. and Messenger, M. T. and Vargo, E. L. and Su, N. Y.}, year={2003}, pages={61–65} }
 @article{vargo_2003, title={Genetic structure of Reticulitermes flavipes and R-virginicus (Isoptera : Rhinotermitidae) colonies in an urban habitat and tracking of colonies following treatment with hexaflumuron bait}, volume={32}, ISSN={["0046-225X"]}, DOI={10.1603/0046-225X-32.5.1271}, abstractNote={Abstract Colony and population genetic structure was determined for Reticulitermes flavipes (Kollar) and Reticulitermes virginicus (Banks) collected from Sentricon Termite Colony Elimination System monitoring stations at an apartment complex in Raleigh, NC. Once in each of 2000, 2001, and 2002, samples of termites were collected from monitoring stations just before the installation of bait tubes containing 0.5% hexaflumuron. Twenty workers from each sample were genotyped at five microsatellite loci. Comparison of worker genotypes among samples provided unambiguous colony associations. Analysis of worker genotypes within colonies coupled with estimates of F-statistics and nestmate relatedness showed that three fourths (30) of the 41 R. flavipes colonies and all three of the R. virginicus colonies were simple families headed by pairs of outbred monogamous reproductives. The remaining R. flavipes colonies were extended families, apparently headed by a few neotenic reproductives. Most colonies appeared to be localized, occupying only a single monitoring station. Termite pressure was initially heavy, with up to five colonies present around a single building simultaneously, but it progressively decreased over time. Of 35 R. flavipes colonies and 1 R. virginicus colony baited in 2000 or 2001, only a single R. flavipes colony was found again 1 yr later, but this colony was not detected the following year. These results suggest that although treatment with hexaflumuron bait successfully suppresses or eliminates Reticulitermes spp. colonies, new colonies can quickly move into areas vacated by treated colonies, but over time continuous baiting can reduce termite pressure and effectively protect structures.}, number={5}, journal={ENVIRONMENTAL ENTOMOLOGY}, author={Vargo, EL}, year={2003}, month={Oct}, pages={1271–1282} }
 @article{vargo_2003, title={Hierarchical analysis of colony and population genetic structure of the eastern subterranean termite, Reticulitermes flavipes, using two classes of molecular markers.}, volume={57}, DOI={10.1554/03-336}, abstractNote={Termites (Isoptera) comprise a large and important group of eusocial insects, yet, in contrast to the eusocial Hymenoptera (ants, bees, wasps), the breeding systems of termites remain poorly understood. In this study, I inferred the breeding system of the subterranean termite Reticulitermes flavipes based on colony and population genetic structure as determined from microsatellite and mitochondrial DNA markers. Termites were sampled from natural wood debris from three undisturbed, forested sites in central North Carolina. In each site, two transects separated by 1 km were sampled at approximately 15-m intervals. A total of 1272 workers collected from 57 collection points were genotyped at six microsatellite loci, and mitochondrial DNA haplotype was determined for a subset of these individuals using either restriction fragment length polymorphism or sequence variation in the AT-rich region. Colonies appeared to be localized: workers from the 57 collection points represented 56 genetically distinct colonies with only a single colony occupying two collection points located 15 m apart. Genetic analysis of family structure and comparisons of estimates of F-statistics (FIT, FIC, FCT) and coefficients of relatedness (r) among nestmate workers with results of computer simulations of potential breeding systems suggested that 77% of all colonies were simple families headed by outbred monogamous pairs, whereas the remaining colonies were extended (inbred) families headed by low numbers of neotenics (about two females and one male) who were the direct offspring of the colony founders. There was no detectable isolation by distance among colonies along transects, suggesting that colony reproduction by budding is not common and that dispersal of reproductives during mating flights is not limited over this distance. Higher-level analysis of the microsatellite loci indicated weak but significant differentiation among sites (FST = 0.06), a distance of 16–38 km, and between transects within sites (FST = 0.06), a distance of 1 km. No significant differentiation at either the transect or site level was detected in the mitochondrial DNA sequence data. These results indicate that the study populations of R. flavipes have a breeding system characterized by monogamous pairs of outbred reproductives and relatively low levels of inbreeding because most colonies do not live long enough to produce neotenics, and those colonies that do generate neotenics contain an effectively small number of them.}, number={12}, journal={Evolution}, author={Vargo, E. L.}, year={2003}, pages={2805–2818} }
 @inbook{husseneder_vargo_grace_2003, title={Molecular genetic methods: New approaches to termite biology}, volume={845}, DOI={10.1021/bk-2003-0845.ch021}, abstractNote={Termites (Isoptera) are of global economic and ecological importance as decomposers of lignocellulose matter. Yet little is known about their biology due to their cryptic feeding and nesting habits. The advent of a variety of molecular genetic techniques provides a powerful method to elucidate many aspects of termite ecology and social organization. We present an overview of currently applied molecular genetic methods, including analyses of proteins, mitochondrial and genomic DNA, in a variety of termite species. These methods complement each other in the description of termite population structure, the identification of colonies and their breeding systems. The increasing application of these and other methods will yield a much improved understanding of termite ecology and social evolution as well as more effective means of controlling pest species.}, booktitle={Wood deterioration and preservation: Advances in our changing world}, publisher={Washington, D.C.: American Chemical Society}, author={Husseneder, C. and Vargo, E. L. and Grace, I. K.}, editor={B. Goodell, D. D. Nicholas and Schultz, T. P.Editors}, year={2003}, pages={358–370} }
 @article{husseneder_vargo_grace_2002, title={Multilocus DNA fingerprinting and microsatellite genotyping: Complementary molecular approaches to investigating colony and population genetic structure in subterranean termites}, volume={40}, number={1}, journal={Sociobiology}, author={Husseneder, C. and Vargo, E. L. and Grace, J. K.}, year={2002}, pages={217–226} }
 @article{passera_aron_vargo_keller_2001, title={Queen control of sex ratio in fire ants}, volume={293}, ISSN={["1095-9203"]}, DOI={10.1126/science.1062076}, abstractNote={
            The haplodiploid sex-determination system of ants gives rise to conflict between queens and workers over colony sex ratios, and the female-biased allocation ratios seen in many species suggest that workers often prevail in this conflict. We exchanged queens between male- and female-specialist colonies of the fire ant
            Solenopsis invicta
            . These exchanges quickly reversed the sex-ratio biases of adopting colonies. The sex ratio of queen-laid eggs differed strongly between male- and female-specialist colonies. These findings suggest that queens can force workers to raise male sexuals by limiting the number of female brood and help to explain why sex investment ratios lie between the queen and worker equilibria in this and many other ant species.
          }, number={5533}, journal={SCIENCE}, author={Passera, L and Aron, S and Vargo, EL and Keller, L}, year={2001}, month={Aug}, pages={1308–1310} }
 @article{vargo_henderson_2000, title={Identification of polymorphic microsatellite loci in the Formosan subterranean termite Coptotermes formosanus Shiraki}, volume={9}, ISSN={["0962-1083"]}, DOI={10.1046/j.1365-294x.2000.0090111935.x}, abstractNote={Molecular EcologyVolume 9, Issue 11 p. 1935-1938 Identification of polymorphic microsatellite loci in the Formosan subterranean termite Coptotermes formosanus Shiraki E. L. Vargo, Corresponding Author E. L. Vargo Department of Entomology, Box 7613, North Carolina State University, Raleigh, NC 27695-7613, USA, Edward L. Vargo. Fax: +1 919 515 7746; E-mail: [email protected]Search for more papers by this authorG. Henderson, G. Henderson Department of Entomology, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USASearch for more papers by this author E. L. Vargo, Corresponding Author E. L. Vargo Department of Entomology, Box 7613, North Carolina State University, Raleigh, NC 27695-7613, USA, Edward L. Vargo. Fax: +1 919 515 7746; E-mail: [email protected]Search for more papers by this authorG. Henderson, G. Henderson Department of Entomology, Louisiana Agricultural Experiment Station, Louisiana State University Agricultural Center, Baton Rouge, LA 70803, USASearch for more papers by this author First published: 25 December 2001 https://doi.org/10.1046/j.1365-294x.2000.0090111935.xCitations: 22Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL References Glenn T (1996) Microsatellite Manual, MsatManV6, ftp://onyx.si.edu/protocols/ Korman AK & Pashley DP (1991) Genetic comparisons among U.S. populations of Formosan subterranean termites. Sociobiology, 19, 41 50. Oetting WS, Lee HK, Flanders DJ, Wiesner GL, Sellers TA, King RA (1995) Linkage analysis with multiplexed short tandem repeat polymorphisms using infrared fluorescence and M13 tailed primers. Genomics, 30, 450 458. Raymond M & Rousset F (1995) GENEPOP (Version 1.2): population genetics software for exact tests and ecumenicism. Journal of Heredity, 86, 248 249. Strong KL & Grace JK (1993) Low allozyme variation in Formosan subterranean termite (Isoptera: Rhinotermitidae) colonies in Hawaii. Pan-Pacific Entomologist, 69, 51 56. Su N-Y & Tamashiro M (1987) An overview of the Formosan subterranean termite (Isoptera: Rhinotermitidae) in the world. In: Biology and Control of the Formosan Subterranean Termite (eds M Tamashiro, N-Y Su), pp. 3 15. College of Agriculture and Human Resources, University of Hawaii, Honolulu. Thorne BL, Traniello JFA, Adams ES, Bulmer M (1999) Reproductive dynamics and colony structure of subterranean termites of the genus Reticulitermes (Isoptera: Rhinotermitidae): a review of the evidence from behavioral, ecological, and genetic studies. Etholology, Ecology and Evolution, 11, 149 169. Vargo EL (2000) Polymorphism at trinucleotide microsatellite loci in the subterranean termite Reticulitermes flavipes. Molecular Ecology, 9, 817 829. Wang J & Grace JK (1999) Current status of Coptotermes Wasmann (Isoptera. Rhinotermitidae) in China, Japan, Australia and the American Pacific. Sociobiology, 33, 295 305. Citing Literature Volume9, Issue11November 2000Pages 1935-1938 ReferencesRelatedInformation}, number={11}, journal={MOLECULAR ECOLOGY}, author={Vargo, EL and Henderson, G}, year={2000}, month={Nov}, pages={1935–1938} }
 @article{vargo_hulsey_2000, title={Multiple glandular origins of queen pheromones in the fire ant Solenopsis invicta}, volume={46}, ISSN={["1879-1611"]}, DOI={10.1016/S0022-1910(99)00226-7}, abstractNote={The poison sac of the fire ant Solenopsis invicta is the only identified glandular source of pheromones produced by a functional ant queen. This structure, which contains the poison gland, has previously been shown to be the source of a releaser pheromone that mediates queen recognition and tending by workers. The poison sac has also been demonstrated to be the source of a primer pheromone that inhibits winged, virgin queens from shedding their wings (dealating) and developing their ovaries. To determine if the poison sac was the only source of these pheromones, we excised the poison sac from queens and observed whether operated queens retained their pheromonal effects. In a first experiment, the poison sac was removed from functional (egg-laying) queens which were then paired with unoperated nestmate queens in small colonies. Counts of the workers surrounding each queen two weeks after the operation showed that queens without poison sac were as effective as their unoperated nestmates in attracting worker retinues. In a second experiment, we removed the poison sacs of virgin queens which had not yet begun laying eggs and thus had not begun producing queen pheromone. After allowing them to develop their ovaries, these individuals produced amounts of queen recognition pheromone comparable to those secreted by unoperated or sham operated virgin queens as determined by bioassay. Testing the head, thorax and abdomens of functional queens separately revealed that the head was the most attractive region in relation to its relative surface area. Bioassays of extracts of two cephalic glands-the mandibular gland and postpharyngeal gland-showed that the postpharyngeal gland is a second source of the queen recognition pheromone. Finally, we found that virgin queens whose poison sacs were removed before they began producing queen pheromone initiated production of a primer pheromone that inhibits winged virgin queens from dealating, indicating that this pheromonal effect also has an additional but as yet undetermined source. These results parallel those on the honey bee in which several of the pheromonal effects of functional queens appear to have multiple glandular sources.}, number={8}, journal={JOURNAL OF INSECT PHYSIOLOGY}, author={Vargo, EL and Hulsey, CD}, year={2000}, month={Aug}, pages={1151–1159} }
 @article{vargo_2000, title={Polymorphism at trinucleotide microsatellite loci in the subterranean termite Reticulitermes flavipes}, volume={9}, ISSN={["1365-294X"]}, DOI={10.1046/j.1365-294x.2000.00915.x}, abstractNote={The subterranean termite Reticulitermes flavipes (Rhinotermitidae) is widespread throughout the eastern U.S.A., where it is important both as a decomposer of wood and as an economic pest. The social organization and modes of colony foundation in Reticulitermes spp. are highly flexible (reviewed by Thorne 1998). However, the cryptic nesting and foraging habits of these subterranean species has made it difficult to conduct extensive studies of their social and spatial organization. Consequently, we have little information on the relative frequencies of the alternate forms of colony organization and modes of reproduction, or how these vary in response to ecological conditions. Genetic markers have great potential for elucidating colony organization and population structure, but there have only been a few studies on Reticulitermes spp. using either allozymes To provide a sensitive tool for investigating colony and population structure, I developed microsatellite markers for R. flavipes. Termites were collected from infested logs of pine and hardwood trees at various locations in North Carolina, USA. Heads of five workers from each of five colonies were used to construct the genomic library. DNA from pooled tissue was extracted using the Wizard Genomic DNA Purification Kit (Promega) after grinding in liquid nitrogen. Library construction and screening was performed largely following the protocol of Glenn (1996). The genomic DNA was digested with Sau 3AI, and fragments 300 –700 bp were selected for cloning into pZErO-2 plasmids (Invitrogen). I transformed TOP10 F ′ cells to obtain a 20 000-clone library. Plated colonies were lifted onto nylon membranes which were probed with synthetic oligonucleotides consisting of 8–10 repeats of a trinucleotide motif rich in AT (AAT, AAC, ATC, AAG and ACT). Thirty-six positive clones were sequenced. Southern blots of plasmid DNA confirmed 36 positives, for which I obtained 23 sequences containing five or more repeats. From these sequences, 20 primer pairs were designed. Microsatellite analysis was performed largely according to the methods of Oetting et al. (1995) in which the first 19 bp of the M13 forward sequencing primer (CACGACGTTGTAAAA-CGAC) is added to the 5 ′ end of one of the specific primers in each pair. The tail was attached to the left primer in each pair, except in the case of Rf 5 –10, in which it was added to the right primer. A fluorescent labelled M13 (M13F-29/IRD 800, Li-Cor) primer was included in the polymerase chain reaction (PCR), yielding labelled product which was detected in a Li-Cor …}, number={6}, journal={MOLECULAR ECOLOGY}, author={Vargo, EL}, year={2000}, month={Jun}, pages={817–820} }
 @article{shoemaker_ross_keller_vargo_werren_2000, title={Wolbachia infections in native and introduced populations of fire ants (Solenopsis spp.)}, volume={9}, ISSN={["1365-2583"]}, DOI={10.1046/j.1365-2583.2000.00233.x}, abstractNote={AbstractWolbachiaare cytoplasmically inherited bacteria that induce a variety of effects with fitness consequences on host arthropods, including cytoplasmic incompatibility, parthenogenesis, male‐killing and feminization. We report here the presence ofWolbachiain native South American populations of the fire antSolenopsisinvicta, but the apparent absence of the bacteria in introduced populations of this pest species in the USA. TheWolbachiastrains in nativeS. invictaare of two divergent types (A and B), and the frequency of infection varies dramatically between geographical regions and social forms of this host. Survey data reveal thatWolbachiaalso are found in other native fire ant species within theSolenopsis saevissimaspecies complex from South America, includingS. richteri. This latter species also has been introduced in the USA, where it lacksWolbachia. Sequence data reveal complete phylogenetic concordance between mtDNA haplotype inS.invictaandWolbachiainfection type (A or B). In addition, the mtDNA and associated group AWolbachiastrain inS.invictaare more closely related to the mtDNA andWolbachiastrain found inS. richterithan they are to the mtDNA and associated group BWolbachiainS. invicta. These data are consistent with historical introgression ofS. richtericytoplasmic elements intoS.invictapopulations, resulting in enhanced infection and mtDNA polymorphisms inS. invicta.Wolbachiamay have significant fitness effects on these hosts (either directly or by cytoplasmic incompatibility) and therefore these microbes potentially could be used in biological control programmes to suppress introduced fire ant populations.}, number={6}, journal={INSECT MOLECULAR BIOLOGY}, author={Shoemaker, DD and Ross, KG and Keller, L and Vargo, EL and Werren, JH}, year={2000}, month={Dec}, pages={661–673} }
 @article{vargo_1999, title={Reproductive development and ontogeny of queen pheromone production in the fire ant Solenopsis invicta}, volume={24}, ISSN={["0307-6962"]}, DOI={10.1046/j.1365-3032.1999.00153.x}, abstractNote={AbstractQueens of the fire ant, Solenopsis invicta Buren, produce several releaser and primer pheromones. Using bioassays, the ontogeny of three of these pheromones related to reproductive development was investigated. Virgin queens, in which the process of wing‐shedding (dealation) serves as an indicator of the initiation of reproductive development, were studied. First, the production of two queen pheromones produced in the poison gland was examined. The pheromone responsible for initiation and maintenance of retinue formation, a releaser effect, was found to be produced in detectable quantities 2 days after dealation, at which time queens showed significant ovary development and many (30%) had started laying eggs. A primer pheromone that inhibits alate virgin queens from dealating was detected in queens 3 days following wing‐shedding, when 80% of the queens were ovipositing. Second, I examined the onset of a pheromone of unknown glandular origin produced by reproductively active virgin queens which leads to their destruction in queenright colonies by stimulating workers to attack and kill them. This pheromone is secreted in quantities detectable by bioassay 2 days after dealation. Thus, in S. invicta, the ontogeny of three distinct queen pheromones is tightly linked with ovary development and initiation of egg laying. These results demonstrate reproductive and communicative functions are closely associated during the transition from potential to functional queen.}, number={4}, journal={PHYSIOLOGICAL ENTOMOLOGY}, author={Vargo, EL}, year={1999}, pages={370–376} }