@article{levine_hillerislambers_petry_usinowicz_crowther_2024, title={Demographic but not competitive time lags can transiently amplify climate-induced changes in vegetation carbon storage}, volume={30}, ISSN={["1365-2486"]}, url={https://doi.org/10.1111/gcb.17432}, DOI={10.1111/gcb.17432}, abstractNote={Abstract How terrestrial ecosystems will accumulate carbon as the climate continues to change is a major source of uncertainty in projections of future climate. Under growth‐stimulating environmental change, time lags inherent in population and community dynamic processes have been posed to dampen, or alternatively amplify, short‐term carbon gain in terrestrial vegetation, but these outcomes can be difficult to predict. To theoretically frame this problem, we developed a simple model of vegetation dynamics that identifies the stage‐structured demographic and competitive processes that could govern the timescales of carbon storage and loss. We show that demographic lags associated with growth‐stimulating environmental change can allow a rapid increase in population‐level carbon storage that is lost back to the atmosphere in later years. However, this transient carbon storage only emerges when environmental change increases the transition of adult individuals into a larger size class that suffers markedly higher mortality. Otherwise, demographic lags simply slow carbon accumulation. Counterintuitively, an analogous tradeoff between maximum adult size and survivorship in two‐species models, coupled with environmental change‐driven replacement, does not generate the transient carbon gain seen in the single‐species models. Instead lags in competitive replacement slow the approach to the eventual carbon trajectory. Together, our results suggest that time lags inherent in demographic and compositional turnover tend to slow carbon accumulation in systems responding to growth‐stimulating environmental change. Only under specific conditions will lagged demographic processes in such systems drive transient carbon accumulation, conditions that investigators can examine in nature to help project future carbon trajectories.}, number={8}, journal={GLOBAL CHANGE BIOLOGY}, author={Levine, Jonathan M. and Hillerislambers, Janneke and Petry, William K. and Usinowicz, Jacob and Crowther, Thomas W.}, year={2024}, month={Aug} }
 @article{blonder_gauzere_iversen_ke_petry_ray_salguero-gomez_sharpless_violle_2023, title={Predicting and controlling ecological communities via trait and environment mediated parameterizations of dynamical models}, volume={3}, ISSN={["1600-0706"]}, DOI={10.1111/oik.09415}, abstractNote={Predicting or controlling the state of an ecological community is a core global change challenge. Dynamical models provide one toolkit, but parameterizing these models can be challenging, and interpretation can be difficult. We here propose rewriting dynamical model parameters in terms of more interpretable and measurable functional traits and environmental variables (trait and environment mediated parameterizations; TEMPs). For prediction, this approach could help make interpretable forecasts of equilibrium community dynamics (species coexistence), invasibility surfaces (dynamics due to biotic context), and responses to environmental change (dynamics due to abiotic context). For control, this approach could help identify policies that yield desired species and trait compositions through perturbations of the abundance of species with certain traits, or of the environment.}, journal={OIKOS}, author={Blonder, Benjamin Wong and Gauzere, Pierre and Iversen, Lars L. and Ke, Po-Ju and Petry, William K. and Ray, Courtenay A. and Salguero-Gomez, Roberto and Sharpless, William and Violle, Cyrille}, year={2023}, month={Mar} }
 @article{villellas_ehrlen_crone_csergo_garcia_laine_roach_salguero-gomez_wardle_childs_et al._2021, title={PHENOTYPIC PLASTICITY MASKS RANGE-WIDE GENETIC DIFFERENTIATION FOR VEGETATIVE BUT NOT REPRODUCTIVE TRAITS IN A SHORT-LIVED PLANT}, volume={8}, ISSN={["1461-0248"]}, DOI={10.1111/ele.13858}, abstractNote={AbstractGenetic differentiation and phenotypic plasticity jointly shape intraspecific trait variation, but their roles differ among traits. In short‐lived plants, reproductive traits may be more genetically determined due to their impact on fitness, whereas vegetative traits may show higher plasticity to buffer short‐term perturbations. Combining a multi‐treatment greenhouse experiment with observational field data throughout the range of a widespread short‐lived herb,Plantago lanceolata, we (1) disentangled genetic and plastic responses of functional traits to a set of environmental drivers and (2) assessed how genetic differentiation and plasticity shape observational trait–environment relationships. Reproductive traits showed distinct genetic differentiation that largely determined observational patterns, but only when correcting traits for differences in biomass. Vegetative traits showed higher plasticity and opposite genetic and plastic responses, masking the genetic component underlying field‐observed trait variation. Our study suggests that genetic differentiation may be inferred from observational data only for the traits most closely related to fitness.}, journal={ECOLOGY LETTERS}, author={Villellas, Jesus and Ehrlen, Johan and Crone, Elizabeth E. and Csergo, Anna Maria and Garcia, Maria B. and Laine, Anna-Liisa and Roach, Deborah A. and Salguero-Gomez, Roberto and Wardle, Glenda M. and Childs, Dylan Z. and et al.}, year={2021}, month={Aug} }
 @article{jones_barks_stott_james_levin_petry_capdevila_che-castaldo_jackson_römer_et al._2021, title={Rcompadre and Rage - two R packages to facilitate the use of the COMPADRE and COMADRE databases and calculation of life history traits from matrix population models}, url={https://doi.org/10.1101/2021.04.26.441330}, DOI={10.1101/2021.04.26.441330}, abstractNote={SummaryMatrix population models (MPMs) are an important tool for biologists seeking to understand the causes and consequences of variation in vital rates (e.g., survival, reproduction) across life cycles. Empirical MPMs describe the age- or stage-structured demography of organisms and usually represent the life history of a population during a particular time frame at a specific geographic location.The COMPADRE Plant Matrix Database and COMADRE Animal Matrix Database are the most extensive resources for MPM data, collectively containing >12,000 individual projection matrices for >1,100 species globally. Although these databases represent an unparalleled resource for researchers, land managers, and educators, the current computational tools available to answer questions with MPMs impose significant barriers to potential COM(P)ADRE database users by requiring advanced knowledge to handle diverse data structures and program custom analysis functions.To close this knowledge gap, we present two interrelated R packages designed to (i) facilitate the use of these databases by providing functions to acquire, quality control, and manage both the MPM data contained in COMPADRE and COMADRE, and a user’s own MPM data (Rcompadre), and (ii) present a range of functions to calculate life history traits from MPMs in support of ecological and evolutionary analyses (Rage). We provide examples to illustrate the use of both.Rcompadre and Rage will facilitate demographic analyses using MPM data and contribute to the improved replicability of studies using these data. We hope that this new functionality will allow researchers, land managers, and educators to unlock the potential behind the thousands of MPMs and ancillary metadata stored in the COMPADRE and COMADRE matrix databases, and in their own MPM data.}, author={Jones, Owen R. and Barks, Patrick and Stott, Iain and James, Tamora D. and Levin, Sam and Petry, William K. and Capdevila, Pol and Che-Castaldo, Judy and Jackson, John and Römer, Gesa and et al.}, year={2021}, month={Apr} }
 @article{jones_barks_stott_james_levin_petry_capdevila_che-castaldo_jackson_romer_et al._2022, title={Rcompadre and Rage-Two R packages to facilitate the use of the COMPADRE and COMADRE databases and calculation of life-history traits from matrix population models}, volume={1}, ISSN={["2041-2096"]}, DOI={10.1111/2041-210X.13792}, abstractNote={Abstract


Matrix population models (MPMs) are an important tool for biologists seeking to understand the causes and consequences of variation in vital rates (e.g. survival, reproduction) across life cycles. Empirical MPMs describe the age‐ or stage‐structured demography of organisms and usually represent the life history of a population during a particular time frame at a specific geographical location.

The COMPADRE Plant Matrix Database and COMADRE Animal Matrix Database are the most extensive resources for MPM data, collectively containing >12,000 individual projection matrices for >1,100 species globally. Although these databases represent an unparalleled resource for researchers, land managers and educators, the current computational tools available to answer questions with MPMs impose significant barriers to potential COM(P)ADRE database users by requiring advanced knowledge to handle diverse data structures and program custom analysis functions.

To close this knowledge gap, we present two interrelated R packages designed to (a) facilitate the use of these databases by providing functions to acquire, quality control and manage both the MPM data contained in COMPADRE and COMADRE, and a user's own MPM data (Rcompadre) and (b) present a range of functions to calculate life‐history traits from MPMs in support of ecological and evolutionary analyses (Rage). We provide examples to illustrate the use of both.

Rcompadre and Rage will facilitate demographic analyses using MPM data and contribute to the improved replicability of studies using these data. We hope that this new functionality will allow researchers, land managers and educators to unlock the potential behind the thousands of MPMs and ancillary metadata stored in the COMPADRE and COMADRE matrix databases, and in their own MPM data.

}, journal={METHODS IN ECOLOGY AND EVOLUTION}, author={Jones, Owen R. and Barks, Patrick and Stott, Iain and James, Tamora D. and Levin, Sam and Petry, William K. and Capdevila, Pol and Che-Castaldo, Judy and Jackson, John and Romer, Gesa and et al.}, year={2022}, month={Jan} }
 @article{jerome_petry_mooney_iler_2021, title={Snow melt timing acts independently and in conjunction with temperature accumulation to drive subalpine plant phenology}, volume={7}, ISSN={["1365-2486"]}, url={https://doi.org/10.1111/gcb.15803}, DOI={10.1111/gcb.15803}, abstractNote={AbstractOrganisms use environmental cues to align their phenology—the timing of life events—with sets of abiotic and biotic conditions that favor the successful completion of their life cycle. Climate change has altered the environmental cues organisms use to track climate, leading to shifts in phenology with the potential to affect a variety of ecological processes. Understanding the drivers of phenological shifts is critical to predicting future responses, but disentangling the effects of temperature from precipitation on phenology is often challenging because they tend to covary. We addressed this knowledge gap in a high‐elevation environment where phenological shifts are associated with both the timing of spring snow melt and temperature. We factorially crossed early snow melt and passive warming treatments to (1) disentangle the effects of snow melt timing and warming on the phenology of flowering and fruiting and reproductive success in three subalpine plant species (Delphinium nuttallianum, Valeriana edulis, and Potentilla pulcherrima); and (2) assess whether snow melt acts via temperature accumulation or some other aspect of the environment (e.g., soil moisture) to affect phenological events. Both the timing and duration of flowering and fruiting responded to the climate treatments, but the effect of snow melt timing and warming varied among species and phenological stages. The combined effects of the treatments on phenology were always additive, and the snow melt treatment often affected phenology even when the warming treatment did not. Despite marked responses of phenology to climate manipulations, the species showed little change in reproductive success, with only one species producing fewer seeds in response to warming (Delphinium, −56%). We also found that snow melt timing can act both through temperature accumulation and as a distinct cue for phenology, and these effects are not mutually exclusive. Our results show that one environmental cue, here snow melt timing, may act through multiple mechanisms to shift phenology.}, journal={GLOBAL CHANGE BIOLOGY}, publisher={Wiley}, author={Jerome, Diana K. and Petry, William K. and Mooney, Kailen A. and Iler, Amy M.}, year={2021}, month={Jul} }
 @article{smith_hodkinson_villellas_catford_csergő_blomberg_crone_ehrlén_garcia_laine_et al._2020, title={Global gene flow releases invasive plants from environmental constraints on genetic diversity}, volume={117}, url={http://dx.doi.org/10.1073/pnas.1915848117}, DOI={10.1073/pnas.1915848117}, abstractNote={
            When plants establish outside their native range, their ability to adapt to the new environment is influenced by both demography and dispersal. However, the relative importance of these two factors is poorly understood. To quantify the influence of demography and dispersal on patterns of genetic diversity underlying adaptation, we used data from a globally distributed demographic research network comprising 35 native and 18 nonnative populations of
            Plantago lanceolata
            . Species-specific simulation experiments showed that dispersal would dilute demographic influences on genetic diversity at local scales. Populations in the native European range had strong spatial genetic structure associated with geographic distance and precipitation seasonality. In contrast, nonnative populations had weaker spatial genetic structure that was not associated with environmental gradients but with higher within-population genetic diversity. Our findings show that dispersal caused by repeated, long-distance, human-mediated introductions has allowed invasive plant populations to overcome environmental constraints on genetic diversity, even without strong demographic changes. The impact of invasive plants may, therefore, increase with repeated introductions, highlighting the need to constrain future introductions of species even if they already exist in an area.
          }, number={8}, journal={Proceedings of the National Academy of Sciences}, publisher={Proceedings of the National Academy of Sciences}, author={Smith, Annabel L. and Hodkinson, Trevor R. and Villellas, Jesus and Catford, Jane A. and Csergő, Anna Mária and Blomberg, Simone P. and Crone, Elizabeth E. and Ehrlén, Johan and Garcia, Maria B. and Laine, Anna-Liisa and et al.}, year={2020}, month={Feb}, pages={4218–4227} }
 @article{petry_kandlikar_kraft_godoy_levine_2018, title={A competition–defence trade‐off both promotes and weakens coexistence in an annual plant community}, volume={106}, url={https://doi.org/10.1111/1365-2745.13028}, DOI={10.1111/1365-2745.13028}, abstractNote={Abstract


Competition–defence trade‐offs have long been thought to promote plant coexistence and increase species diversity. However, insights from modern coexistence theory clarify that such trade‐offs alone cannot sustain coexistence. Coexistence also requires stabilising niche differences and the ability of competitor populations to persist under consumer pressure. Despite the breadth of potential consequences of competition–defence trade‐offs, we have little mechanistic understanding of how they affect diversity in natural communities.

We investigated the effects of seed harvesting by ants on coexistence in an annual plant community. We parameterised a model of plant competitive population dynamics with data from two field experiments: (a) plant demographic rates and competition coefficients determined by growing plants alone and against intra‐ and interspecific competitor density gradients; (b) plant fitness losses to ant consumers determined by measuring seed removal from experimental depots. We tested for a trade‐off between a plant species’ demographic potential and its susceptibility to consumption and then determined the bounds of ant effects on pairwise and multispecies coexistence by comparing model projections with and without seed consumption.

Ants harvested seeds of all plant species, but they strongly preferred the competitively superior large seeded species, inducing a competition–defence trade‐off. Unequal seed loss to ants changed competition‐based fitness hierarchies, affecting both the number and identities of plant species pairs that were predicted to coexist compared to a scenario without ants. The trade‐off most often prevented coexistence by severely disadvantaging the superior competitor or excluding species directly through overconsumption, and a simulated reduction in the overall consumption rate opened few additional opportunities for coexistence. Ant exacerbation of average fitness differences was particularly disruptive to multispecies coexistence, where niche differences were insufficient to stabilise the coexistence of plant triplets and quadruplets.

Synthesis. Our results show that the presence of a competition–defence trade‐off in a community with stabilising niche differences does not always increase diversity. Instead, the full range of diversity outcomes—positive and negative changes in species number and changes in the identity of the dominant—are possible. Taken together, our results support the emerging paradigm that consumers have wide‐ranging impacts on plant diversity and suggest that variation in consumer pressure may be an important driver of large‐scale diversity patterns.

}, number={5}, journal={Journal of Ecology}, publisher={Wiley}, author={Petry, William K. and Kandlikar, Gaurav S. and Kraft, Nathan J. B. and Godoy, Oscar and Levine, Jonathan M.}, editor={Bartomeus, IgnasiEditor}, year={2018}, month={Sep}, pages={1806–1818} }
 @article{romero_gonçalves-souza_kratina_marino_petry_sobral-souza_roslin_2018, title={Global predation pressure redistribution under future climate change}, volume={8}, url={https://doi.org/10.1038/s41558-018-0347-y}, DOI={10.1038/s41558-018-0347-y}, abstractNote={How climate affects biotic interactions is a question of urgent concern1–3. Theory predicts that biotic interactions are stronger at lower latitudes4–6. However, the role of climate in governing these patterns is typically assumed, rather than explicitly tested. Here, we dissected the influence of climatic descriptors on predation pressure using data from a global experiment with model caterpillars. We then used projections of future climate change to predict shifts in predation pressure. Climate, particularly components of temperature, explained latitudinal and elevational patterns of predation better than latitude or elevation by themselves. Projected predation pressure was greater under higher temperatures and more stable climates. Increased climatic instability projected for the near future predicts a general decrease in predation pressure over time. By identifying the current climatic drivers of global patterns in a key biotic interaction, we show how shifts in these drivers could alter the functioning of terrestrial ecosystems and their associated services. A global experiment using model caterpillars shows that climate explains patterns of predation better than latitude or elevation alone. Predation pressure is found to be greater under higher temperatures and more stable climatic conditions.}, number={12}, journal={Nature Climate Change}, publisher={Springer Science and Business Media LLC}, author={Romero, Gustavo Q. and Gonçalves-Souza, Thiago and Kratina, Pavel and Marino, Nicholas A. C. and Petry, William K. and Sobral-Souza, Thadeu and Roslin, Tomas}, year={2018}, month={Dec}, pages={1087–1091} }
 @article{inducibility of chemical defences in young oak trees is stronger in species with high elevational ranges_2019, volume={39}, url={http://dx.doi.org/10.1093/treephys/tpy139}, DOI={10.1093/treephys/tpy139}, abstractNote={Elevational gradients have been highly useful for understanding the underlying forces driving variation in plant traits and plant-insect herbivore interactions. A widely held view from these studies has been that greater herbivory under warmer and less variable climatic conditions found at low elevations has resulted in stronger herbivore selection on plant defences. However, this prediction has been called into question by conflicting empirical evidence, which could be explained by a number of causes such as an incomplete assessment of defensive strategies (ignoring other axes of defence such as defence inducibility) or unaccounted variation in abiotic factors along elevational clines. We conducted a greenhouse experiment testing for inter-specific variation in constitutive leaf chemical defences (phenolic compounds) and their inducibility in response to feeding by gypsy moth larvae (Lymantria dispar L., Lepidoptera) using saplings of 18 oak (Quercus, Fagaceae) species. These species vary in their elevational distribution and together span >2400 m in elevation, therefore allowing us to test for among-species elevational clines in defences based on the elevational range of each species. In addition, we further tested for elevational gradients in the correlated expression of constitutive defences and their inducibility and for associations between defences and climatic factors potentially underlying elevational gradients in defences. Our results showed that oak species with high elevational ranges exhibited a greater inducibility of phenolic compounds (hydrolysable tannins), but this gradient was not accounted for by climatic predictors. In contrast, constitutive defences and the correlated expression of constitutive phenolics and their inducibility did not exhibit elevational clines. Overall, this study builds towards a more robust and integrative understanding of how multivariate plant defensive phenotypes vary along ecological gradients and their underlying abiotic drivers.}, number={4}, journal={Tree Physiology}, publisher={Oxford University Press (OUP)}, year={2019}, month={Apr}, pages={606–614} }
 @article{interspecific variation in leaf functional and defensive traits in oak species and its underlying climatic drivers_2018, volume={13}, DOI={10.1371/journal.pone.0202548}, abstractNote={Plants exhibit a diverse set of functional traits and ecological strategies which reflect an adaptation process to the biotic and abiotic components of the environment. The Plant Economic Spectrum organizes these traits along a continuum from conservative to acquisitive resource use strategies and shows how the abiotic environment governs a species’ position along the continuum. However, this framework does not typically account for leaf traits associated with herbivore resistance, despite fundamental metabolic links (and therefore co-variance) between resource use traits and defensive traits. Here we analyzed a suite of leaf traits associated with either resource use (specific leaf area [SLA], nutrients and water content) or defenses (phenolic compounds) for saplings of 11 species of oaks (Quercus spp.), and further investigated whether climatic variables underlie patterns of trait interspecific variation. An ordination of leaf traits revealed the primary axis of trait variation to be leaf economic spectrum traits associated with resource use (SLA, nitrogen, water content) in conjunction with a defensive trait (condensed tannins). Secondary and tertiary axes of trait variation were mainly associated with other defensive traits (lignins, flavonoids, and hydrolysable tannins). Within the primary axis we found a trade-off between resource use traits and both water content and condensed tannins; species with high SLA and leaf N values invested less in condensed tannins and viceversa. Moreover, temperature and precipitation mediated the trait space occupied by species, such that species distributed in warmer and drier climates had less leaf N, lower SLA, and more defenses (condensed tannins, lignins and flavonoids), whereas opposite values were observed for species distributed in colder and wetter climates. These results emphasize the role of abiotic controls over all-inclusive axes of trait variation and contribute to a more complete understanding of interspecific variation in plant functional strategies.}, number={8}, journal={PLOS ONE}, year={2018}, month={Aug}, pages={e0202548} }
 @article{elevational gradients in plant defences and insect herbivory: recent advances in the field and prospects for future research_2018, volume={41}, DOI={10.1111/ecog.03184}, abstractNote={Classic research on elevational gradients in plant–herbivore interactions holds that insect herbivore pressure is stronger under warmer, less seasonal climates characteristic of low elevations, and that this in turn selects for increased defence in low‐ (relative to high‐) elevation plants. However, recent work has questioned this paradigm, arguing that it overly simplifies the ecological complexity in which plant–insect herbivore interactions are embedded along elevational gradients. Numerous biotic and abiotic factors vary with elevation, and their simultaneous influences are the focus of current work on elevational gradients in insect herbivory and plant defences. The present review 1) synthesizes current knowledge on elevational gradients in plant–insect herbivore interactions; 2) critically analyses research gaps and highlights recent advances that contribute to filling these gaps; and 3) outlines new research opportunities to uncover underlying mechanisms and build towards a unified theory on elevational gradients. We conclude that the next generation of studies should embrace community complexity – including multi‐trophic dynamics and the multivariate nature of plant defence – and to do so by combining observational data, manipulative experiments and emerging analytical tools.}, number={9}, journal={Ecography}, year={2018}, pages={1485–1496} }
 @article{roslin_hardwick_novotny_petry_andrew_asmus_barrio_basset_boesing_bonebrake_et al._2017, title={Higher predation risk for insect prey at low latitudes and elevations}, volume={356}, url={https://doi.org/10.1126/science.aaj1631}, DOI={10.1126/science.aaj1631}, abstractNote={Risky in the tropics
          
            It is well known that diversity increases toward the tropics. Whether this increase translates into differences in interaction rates among species, however, remains unclear. To simplify the problem, Roslin
            et al.
            tested for predation rates by using a single approach involving model caterpillars across six continents. Predator attack rates were higher toward the equator, but only for arthropod predators.
          
          
            Science
            , this issue p.
            742
          }, number={6339}, journal={Science}, publisher={American Association for the Advancement of Science (AAAS)}, author={Roslin, Tomas and Hardwick, Bess and Novotny, Vojtech and Petry, William K. and Andrew, Nigel R. and Asmus, Ashley and Barrio, Isabel C. and Basset, Yves and Boesing, Andrea Larissa and Bonebrake, Timothy C. and et al.}, year={2017}, month={May}, pages={742–744} }
 @article{caradonna_petry_brennan_cunningham_bronstein_waser_sanders_2017, title={Interaction Rewiring and the Rapid Turnover of Plant-Pollinator Networks}, volume={20}, DOI={10.1111/ele.12740}, abstractNote={AbstractWhether species interactions are static or change over time has wide‐reaching ecological and evolutionary consequences. However, species interaction networks are typically constructed from temporally aggregated interaction data, thereby implicitly assuming that interactions are fixed. This approach has advanced our understanding of communities, but it obscures the timescale at which interactions form (or dissolve) and the drivers and consequences of such dynamics. We address this knowledge gap by quantifying the within‐season turnover of plant–pollinator interactions from weekly censuses across 3 years in a subalpine ecosystem. Week‐to‐week turnover of interactions (1) was high, (2) followed a consistent seasonal progression in all years of study and (3) was dominated by interaction rewiring (the reassembly of interactions among species). Simulation models revealed that species’ phenologies and relative abundances constrained both total interaction turnover and rewiring. Our findings reveal the diversity of species interactions that may be missed when the temporal dynamics of networks are ignored.}, number={3}, journal={Ecology Letters}, author={CaraDonna, Paul J. and Petry, William K. and Brennan, Ross M. and Cunningham, James L. and Bronstein, Judith L. and Waser, Nickolas M. and Sanders, Nathan J.}, editor={Jordan, FerencEditor}, year={2017}, pages={385–394} }
 @article{petry_soule_iler_chicas-mosier_inouye_miller_mooney_2016, title={Sex-Specific Responses to Climate Change in Plants Alter Population Sex Ratio and Performance}, volume={353}, DOI={10.1126/science.aaf2588}, abstractNote={Changing sex ratios
          
            Climate-warming temperatures might be expected to affect the sex ratio of species if sex determination is temperature-dependent. Petry
            et al.
            show that indirect climate effects could also alter sex ratios in species in which sex is genetically determined and damage reproductive fitness (see the Perspective by Etterson and Mazer). Over four decades, sex ratios in populations of a dioecious alpine plant have shifted toward females as a result of the different water needs of the male and female plants. The lack of males has reduced the reproductive success and fitness of the females. Similar subtle differences between sexes in environmental sensitivities could eventually lead to population declines.
          
          
            Science
            , this issue p.
            69
            ; see also p.
            32
          }, number={6294}, journal={Science}, author={Petry, William K. and Soule, Judith D. and Iler, Amy M. and Chicas-Mosier, Ana and Inouye, David W. and Miller, Tom E. X. and Mooney, Kailen A.}, year={2016}, month={Jul}, pages={69–71} }
 @article{plant defence responses to volatile alert signals are population-specific_2016, volume={125}, DOI={10.1111/oik.02891}, abstractNote={Herbivore‐induced volatiles are widespread in plants. They can serve as alert signals that enable neighbouring leaves and plants to pre‐emptively increase defences and avoid herbivory damage. However, our understanding of the factors mediating volatile organic compound (VOC) signal interpretation by receiver plants and the degree to which multiple herbivores affect VOC signals is still limited. Here we investigated whether plant responses to damage‐induced VOC signals were population specific. As a secondary goal, we tested for interference in signal production or reception when plants were subjected to multiple types of herbivore damage. We factorially crossed the population sources of paired Phaseolus lunatus plants (same versus different population sources) with a mechanical damage treatment to one member of the pair (i.e. the VOC emitter, damaged versus control), and we measured herbivore damage to the other plant (the VOC receiver) in the field. Prior to the experiment, both emitter and receiver plants were naturally colonized by aphids, enabling us to test the hypothesis that damage from sap‐feeding herbivores interferes with VOC communication by including emitter and receiver aphid abundances as covariates in our analyses. One week after mechanical leaf damage, we removed all the emitter plants from the field and conducted fortnightly surveys of leaf herbivory. We found evidence that receiver plants responded using population‐specific ‘dialects’ where only receivers from the same source population as the damaged emitters suffered less leaf damage upon exposure to the volatile signals. We also found that the abundance of aphids on both emitter and receiver plants did not alter this volatile signalling during both production and reception despite well‐documented defence crosstalk within individual plants that are simultaneously attacked by multiple herbivores. Overall, these results show that plant communication is highly sensitive to genetic relatedness between emitter and receiver plants and that communication is resilient to herbivore co‐infestation.}, number={7}, journal={Oikos}, year={2016}, pages={950–956} }
 @article{trade-offs between constitutive and induced defences drive geographical and climatic clines in pine chemical defences_2014, volume={17}, DOI={10.1111/ele.12253}, abstractNote={AbstractThere is increasing evidence that geographic and climatic clines drive the patterns of plant defence allocation and defensive strategies. We quantified early growth rate and both constitutive and inducible chemical defences of 18 Pinaceae species in a common greenhouse environment and assessed their defensive allocation with respect to each species' range across climatic gradients spanning 31o latitude and 2300 m elevation. Constitutive defences traded‐off with induced defences, and these defensive strategies were associated with growth rate such that slow‐growing species invested more in constitutive defence, whereas fast‐growing species invested more in inducible defence. The position of each pine species along this trade‐off axis was in turn associated with geography; moving poleward and to higher elevations, growth rate and inducible defences decreased, while constitutive defence increased. These geographic patterns in plant defence were most strongly associated with variation in temperature. Climatic and geographical clines thus act as drivers of defence profiles by mediating the constraints imposed by trade‐offs, and this dynamic underlays global patterns of defence allocation.}, number={5}, journal={Ecology Letters}, year={2014}, month={May}, pages={537–546} }
 @article{petry_perry_fremgen_rudeen_lopez_dryburgh_mooney_2013, title={Mechanisms Underlying Plant Sexual Dimorphism in Multi-Trophic Arthropod Communities}, volume={94}, DOI={10.1890/12-2170.1}, abstractNote={A growing body of research documents the importance of plant genetic effects on arthropod community structure. However, the mechanisms underlying these effects are often unclear. Additionally, plant genetic effects have largely been quantified in common gardens, thus inflating the estimates of their importance by minimizing levels of natural variation. Using Valeriana edulis, a dioecious plant with genetically based sex determination, we conducted surveys and experiments on wild‐grown individuals to document field patterns of arthropod association between the sexes and the mechanisms underlying these plant genetic effects. Three years of surveys revealed strong and consistent sex‐biased arthropod association in wild‐grown plants: female plants supported 4‐fold, 1.5‐fold, and 4‐fold higher densities of aphids, aphid predators, and aphid‐tending ants, respectively, compared to males. There was mixed evidence that the female bias for aphids was due to higher plant quality, while we found no difference between plant sexes in aphid preference or the top‐down effects of predators and tending ants. Female bias for ants was due to both the greater attractiveness of female plants (direct effect mediated by floral nectar) and an independent, weaker effect of higher aphid abundance on females (density‐mediated indirect effect). Conversely, the female bias for predators was driven solely by the greater attractiveness of female plants. We did not find interaction modification, i.e., ant–aphid and predator–aphid interactions were equivalent between plant sexes. Plant sex explained 0.24%, 2.28%, and 4.42% of the variance in aphids, predators, and ants, respectively, values comparable to but slightly weaker than those previously reported from common‐garden studies. In contrast to the prediction of diminished plant genetic effects with increasing trophic level, we show how weak indirect effects on predators and parasitoids (via herbivores) can be complemented by strong direct effects via common plant traits (floral resources). In summary, we document direct and indirect effects of genetically based sex on a multi‐trophic arthropod community that were expressed in wild‐grown plants across multiple years.}, number={9}, journal={Ecology}, author={Petry, William K. and Perry, Kayla I. and Fremgen, Aleshia and Rudeen, Sarah K. and Lopez, Mitchell and Dryburgh, John and Mooney, Kailen A.}, year={2013}, month={Sep}, pages={2055–2065} }
 @article{petry_perry_mooney_2012, title={Influence of Macronutrient Imbalance on Native Ant Foraging and Interspecific Interactions in the Field}, volume={37}, DOI={10.1111/j.1365-2311.2012.01349.x}, abstractNote={1. Ants interact with a diversity of organisms. These interactions, coupled with their abundance, cause ants to have ecologically important effects across multiple trophic levels.2. Empirical study of ant nutritional ecology has led to the prediction that a macronutrient imbalance will affect ant behaviour and interspecific interactions that underlie these broad‐scale effects. Excess carbohydrate relative to protein is predicted to increase ant aggressiveness, predatory tendency and foraging activity, and to decrease collection of hemipteran honeydew and plant nectar.3. In field experiments conducted in 2009 and 2010, captive colony fragments of a native ant, Formica podzolica (Hymenoptera: Formicidae), were provided with either simulated prey or carbohydrate solution ad libitum. Foraging behaviours and interactions with flowers, myrmecophilous aphids and aphid natural enemies on wild‐grown plants were documented.4. Strong effects of macronutrient imbalance on foraging manifested quickly and consistently across colonies; in accordance with predictions, prey‐fed foragers collected both honeydew and floral nectar, whereas carbohydrate‐fed ants ceased collecting these resources. Counter to predictions, carbohydrate‐fed ants dramatically lowered their activity levels and did not prey upon aphids.5. Ants had no effect on aphid enemies in 2009, when the latter were relatively rare, but decreased their abundance in 2010. Despite this protection, the net effect of ants on aphids was negative (measured only in 2009). Prey‐fed ants demonstrated a strong preference for honeydew over floral nectar, thus demonstrating that a macronutrient imbalance may lead to different interactions with similar resources.6. This study links ant nutrition and community ecology by demonstrating the rapid, asymmetric and multitrophic consequences of nutritionally mediated behaviour.}, number={3}, journal={Ecological Entomology}, author={Petry, William K. and Perry, Kayla I. and Mooney, Kailen A.}, year={2012}, month={Jun}, pages={175–183} }
 @article{mooney_fremgen_petry_2012, title={Plant Sex and Induced Responses Independently Influence Herbivore Performance, Natural Enemies and Aphid-Tending Ants}, volume={6}, DOI={10.1007/s11829-012-9204-5}, number={4}, journal={Arthropod-Plant Interactions}, author={Mooney, Kailen A. and Fremgen, Aleshia and Petry, William K.}, year={2012}, month={Dec}, pages={553–560} }
 @article{petry_foré_fielden_kim_2010, title={A Quantitative Comparison of Two Sample Methods for Collecting Amblyomma Americanum and Dermacentor Variabilis (Acari: Ixodidae) in Missouri}, volume={52}, DOI={10.1007/s10493-010-9373-9}, abstractNote={In studies of tick communities, sampling methodology may influence observed patterns. The objective of this study was to compare two sampling methods, dragging and dry ice baiting, in two habitats to assess abundance of off-host ticks. Tick communities were monitored from March to December in a forested and an old-field habitat in northeast Missouri. In each habitat, eight drag and eight dry ice bait samples were collected every 2 weeks on a permanent grid. The most common ticks collected were all life stages of Amblyomma americanum L. and adult and larval Dermacentor variabilis Say. Capture data was analyzed to determine if there were differences due to sampling method, habitat or an interaction for each life stage of each species across the entire monitoring period. Data indicate that there were differences in the methods. Significantly more A. americanum nymphs were captured by bait sampling. Dragging captured significantly more larval A. americanum. Significantly more larval and nymphal A. americanum and larval D. variabilis were caught in the forest, whereas significantly more adult D. variabilis were collected in the field. Significant interaction between site and method was found for A. americanum adults and D. variabilis larvae. These differences are likely due to differences in behavior among species and developmental age that interact with microclimate. These data indicate that community monitoring studies should use multiple sampling methodologies to avoid bias. While comparing these methods, the first documented collection of off-host Ixodes scapularis Say in Adair County, Missouri was made.}, number={4}, journal={Experimental and Applied Acarology}, author={Petry, William K. and Foré, Stephanie A. and Fielden, Laura J. and Kim, Hyun-Joo}, year={2010}, month={Dec}, pages={427–438} }