@article{ngor_palmer-young_burciaga nevarez_russell_leger_giacomini_pinilla-gallego_irwin_mcfrederick_2020, title={Cross-infectivity of honey and bumble bee-associated parasites across three bee families}, volume={147}, ISSN={0031-1820 1469-8161}, url={http://dx.doi.org/10.1017/S0031182020001018}, DOI={10.1017/S0031182020001018}, abstractNote={Abstract Recent declines of wild pollinators and infections in honey, bumble and other bee species have raised concerns about pathogen spillover from managed honey and bumble bees to other pollinators. Parasites of honey and bumble bees include trypanosomatids and microsporidia that often exhibit low host specificity, suggesting potential for spillover to co-occurring bees via shared floral resources. However, experimental tests of trypanosomatid and microsporidial cross-infectivity outside of managed honey and bumble bees are scarce. To characterize potential cross-infectivity of honey and bumble bee-associated parasites, we inoculated three trypanosomatids and one microsporidian into five potential hosts – including four managed species – from the apid, halictid and megachilid bee families. We found evidence of cross-infection by the trypanosomatids Crithidia bombi and C. mellificae, with evidence for replication in 3/5 and 3/4 host species, respectively. These include the first reports of experimental C. bombi infection in Megachile rotundata and Osmia lignaria, and C. mellificae infection in O. lignaria and Halictus ligatus. Although inability to control amounts inoculated in O. lignaria and H. ligatus hindered estimates of parasite replication, our findings suggest a broad host range in these trypanosomatids, and underscore the need to quantify disease-mediated threats of managed social bees to sympatric pollinators.}, number={12}, journal={Parasitology}, publisher={Cambridge University Press (CUP)}, author={Ngor, Lyna and Palmer-Young, Evan C. and Burciaga Nevarez, Rodrigo and Russell, Kaleigh A. and Leger, Laura and Giacomini, Sara June and Pinilla-Gallego, Mario S. and Irwin, Rebecca E. and McFrederick, Quinn S.}, year={2020}, month={Jun}, pages={1290–1304} }
 @article{youngsteadt_irwin_fowler_bertone_giacomini_kunz_suiter_sorenson_2018, title={Venus Flytrap Rarely Traps Its Pollinators}, volume={191}, ISSN={0003-0147 1537-5323}, url={http://dx.doi.org/10.1086/696124}, DOI={10.1086/696124}, abstractNote={Because carnivorous plants rely on arthropods as pollinators and prey, they risk consuming would-be mutualists. We examined this potential conflict in the Venus flytrap (Dionaea muscipula), whose pollinators were previously unknown. Diverse arthropods from two classes and nine orders visited flowers; 56% of visitors carried D. muscipula pollen, often mixed with pollen of coflowering species. Within this diverse, generalized community, certain bee and beetle species appear to be the most important pollinators, on the basis of their abundance, pollen load size, and pollen fidelity. Dionaea muscipula prey spanned four invertebrate classes and 11 orders; spiders, beetles, and ants were most common. At the family and species levels, few taxa were shared between traps and flowers, yielding a near-zero value of niche overlap for these potentially competing structures. Spatial separation of traps and flowers may contribute to partitioning the invertebrate community between nutritional and reproductive functions in D. muscipula.}, number={4}, journal={The American Naturalist}, publisher={University of Chicago Press}, author={Youngsteadt, Elsa and Irwin, Rebecca E. and Fowler, Alison and Bertone, Matthew A. and Giacomini, Sara June and Kunz, Michael and Suiter, Dale and Sorenson, Clyde E.}, year={2018}, month={Apr}, pages={539–546} }
 @article{palmer-young_hogeboom_kaye_donnelly_andicoechea_connon_weston_skyrm_irwin_adler_2017, title={Context-dependent medicinal effects of anabasine and infection-dependent toxicity in bumble bees}, volume={12}, ISSN={1932-6203}, url={http://dx.doi.org/10.1371/journal.pone.0183729}, DOI={10.1371/journal.pone.0183729}, abstractNote={Background Floral phytochemicals are ubiquitous in nature, and can function both as antimicrobials and as insecticides. Although many phytochemicals act as toxins and deterrents to consumers, the same chemicals may counteract disease and be preferred by infected individuals. The roles of nectar and pollen phytochemicals in pollinator ecology and conservation are complex, with evidence for both toxicity and medicinal effects against parasites. However, it remains unclear how consistent the effects of phytochemicals are across different parasite lineages and environmental conditions, and whether pollinators actively self-medicate with these compounds when infected. Approach Here, we test effects of the nectar alkaloid anabasine, found in Nicotiana, on infection intensity, dietary preference, and survival and performance of bumble bees (Bombus impatiens). We examined variation in the effects of anabasine on infection with different lineages of the intestinal parasite Crithidia under pollen-fed and pollen-starved conditions. Results We found that anabasine did not reduce infection intensity in individual bees infected with any of four Crithidia lineages that were tested in parallel, nor did anabasine reduce infection intensity in microcolonies of queenless workers. In addition, neither anabasine nor its isomer, nicotine, was preferred by infected bees in choice experiments, and infected bees consumed less anabasine than did uninfected bees under no-choice conditions. Furthermore, anabasine exacerbated the negative effects of infection on bee survival and microcolony performance. Anabasine reduced infection in only one experiment, in which bees were deprived of pollen and post-pupal contact with nestmates. In this experiment, anabasine had antiparasitic effects in bees from only two of four colonies, and infected bees exhibited reduced—rather than increased—phytochemical consumption relative to uninfected bees. Conclusions Variation in the effect of anabasine on infection suggests potential modulation of tritrophic interactions by both host genotype and environmental variables. Overall, our results demonstrate that Bombus impatiens prefer diets without nicotine and anabasine, and suggest that the medicinal effects and toxicity of anabasine may be context dependent. Future research should identify the specific environmental and genotypic factors that determine whether nectar phytochemicals have medicinal or deleterious effects on pollinators.}, number={8}, journal={PLOS ONE}, publisher={Public Library of Science (PLoS)}, author={Palmer-Young, Evan C. and Hogeboom, Alison and Kaye, Alexander J. and Donnelly, Dash and Andicoechea, Jonathan and Connon, Sara June and Weston, Ian and Skyrm, Kimberly and Irwin, Rebecca E. and Adler, Lynn S.}, editor={Hull, J. JoeEditor}, year={2017}, month={Aug}, pages={e0183729} }