1. Organisms can respond to changing climatic conditions in multiple ways including changes in phenology, body size or morphology, and range shifts. Understanding how developmental temperatures affect insect life-history timing and morphology is crucial because body size and morphology affect multiple aspects of life history, including dispersal ability, while phenology can shape population performance and community interactions. 2. We experimentally assessed how developmental temperatures experienced by aquatic larvae affected survival, phenology, and adult morphology of dragonflies (Pachydiplax longipennis). Larvae were reared under 3 environmental temperatures: ambient, +2.5 °C, and +5 °C, corresponding to temperature projections for our study area 50 and 100 years in the future, respectively. Experimental temperature treatments tracked naturally-occurring variation. 3. We found clear effects of temperature in the rearing environment on survival and phenology: dragonflies reared at the highest temperatures had the lowest survival rates, and emerged from the larval stage approximately 3 weeks earlier than animals reared at ambient temperatures. There was no effect of rearing temperature on overall body size. Although neither the relative wing nor thorax size was affected by warming, a non-significant trend towards an interaction between sex and warming in relative thorax size suggests that males may be more sensitive to warming than females, a pattern that should be investigated further. 4. Warming strongly affected survival in the larval stage and the phenology of adult emergence. Understanding how warming in the developmental environment affects later life-history stages is critical to interpreting the consequences of warming for organismal performance.

Warming due to climate change is expected to alter species interactions. These interactions are shaped by components of individual behavior, particularly foraging behaviors. However, few studies consider species' behavioral responses to warming to predict how species interactions will be affected by warming. We chose two complementary approaches to examine how climate warming may affect the behavior and interactions of aquatic intraguild predators. First, we measured behavioral responses to warming in six larval dragonfly species, expecting that feeding rate and activity would increase with temperature. Secondly, we conducted intraguild predation (IGP) trials with three species to understand how temperature affects IGP, and if species' behavioral responses to warming are indicative of the outcome of IGP interactions. Warming increased feeding rates by 42% on average across species but had no effect on activity rate. The magnitude of change in feeding rate was positively correlated with the maximum temperatures species experience across their ranges. Lastly, warming increased rates of IGP twofold, however, species' behavioral responses alone were not predictive of their susceptibility to become IG prey of other larvae at warmer temperatures. Our results provide evidence that IGP interactions may be greatly affected by future increases in temperature; however, activity responses to warming alone are weak predictors of the outcomes of these interactions. Future studies should consider other species' traits when forecasting the effects of climate change on species interactions.

Senior positions in academia such as tenured faculty and editorial positions often exhibit large gender imbalances across a broad range of research disciplines. The forces driving these imbalances have been the subject of extensive speculation and a more modest body of research. Given the central role publications play in determining individual outcomes and progress in academic settings, unequal patterns of authorship across gender could be a potent driver of observed gender imbalance in academia. Here, we investigate patterns of co-authorship across four journals in ecology and evolutionary biology at four time-points spanning four decades. Co-authorship patterns are of interest because collaborations are important in scientific research, affecting individual researcher productivity, and increasingly, funding opportunities. Based on inferred gender from set criteria, we found significant differences between male and female researchers in their tendency to publish with female co-authors. Specifically, compared to women, male researchers in the last author position were more likely to co-author papers with other males. While we did find that the proportion of female coauthors has increased modestly over the last thirty years, this is strongly correlated with an increase in the average number of authors per paper over time. Additionally, the proportion of female coauthors on papers remains well below the proportion of PhDs awarded to females in biology.

Climate warming affects ectotherms globally, yet we know little regarding the variability in species' responses to warming, particularly in early life stages. Additionally, intraspecific variation in response to warming is understudied but may determine species' resilience to warming. To assess how temperature affects egg development rate in co-occurring dragonfly species, we manipulated temperature (range: 22-31°C) and measured time to hatching. Warming decreased egg development time across all species, indicating that while climate warming will advance hatching phenology, maintained synchrony in hatching order will likely not affect species interactions. Our second experiment examined early life-history responses to warming in the dot-tailed whiteface (Leucorrhinia intacta (Hagen, 1861)) dragonfly. We measured time to hatching, hatchling size, growth rate, and survival at four temperatures (23-30°C), including a treatment with increased thermal variation. Warming resulted in smaller hatchlings with increased growth and mortality rates, whereas higher thermal variation did not have effects different from those of warming alone. We observed significant intraspecific variation in the responses to warming in both egg development time and hatchling size and this variation was correlated with date of oviposition. High levels of intraspecific variation may be important in buffering populations from the effects of climate warming.Key words: body size, climate change, development, ectotherm, life history, Odonata, survival. Résumé :Si le réchauffement climatique a une incidence sur les organismes ectothermes en général, les connaissances sur la variabilité des réactions des espèces au réchauffement sont limitées, particulièrement pour les premières étapes du cycle de vie. Les variations intraspécifiques de la réaction au réchauffement sont également sous-étudiées même si elles pourraient déter-miner la résilience des espèces au réchauffement. Pour évaluer l'influence de la température sur le taux de développement des oeufs chez des espèces de libellules cooccurrentes, nous avons manipulé la température (fourchette : 22 à 31°C) et mesuré la durée d'incubation. Le réchauffement réduisait la durée de développement des oeufs pour toutes les espèces, ce qui indique que, si le réchauffement climatique accélérera la phénologie de l'éclosion, le maintien du synchronisme de l'ordre d'éclosion n'aura vraisemblablement pas d'incidence sur les interactions entre espèces. Notre deuxième expérience se penchait sur les réactions au réchauffement durant les premières étapes du cycle de vie de la leucorrhine mouchetée (Leucorrhinia intacta (Hagen, 1861)). Nous avons mesuré la durée d'incubation, la taille des bébés nouvellement éclos, le taux de croissance et la survie à quatre températures (de 23 à 30°C), incluant un traitement comprenant des variations de température accrues. Le réchauffement produisait des bébés plus petits présentant des taux de croissance et de mortalité accrus, alors que l'augmentation des variations de...

Traits have been used extensively to predict and understand performance in response to the abiotic environment, but their role for understanding competitive interactions is less understood, especially in nonplant systems. In this study, we evaluate how traits interact with intraspecific density to modulate performance (per capita birth rate) and whether the traits associated with intraspecific competitive ability are similar across multiple species. We used an experimental system of four cladoceran zooplankton species, experimentally manipulated the density of conspecifics, and measured a range of morphological and life history characteristics (body mass, body length, second antenna length, eye diameter, relative growth rate, age at first reproduction, and birth rate). With causal modeling, we identified significant trait-density relationships for three out of four species, although the specific traits that predicted birth rate varied from species to species. In general, individuals at higher densities displayed smaller morphological traits and shifts towards slower relative growth rates and delayed onset of reproduction. We also asked more generally if there are consistent trait-mediated impacts of density across multiple species. The interspecific model identified significant trait-density relationships for body length, age at first reproduction, and relative growth rate. Unexpectedly, we found little evidence for trait-based competition due to mechanisms such as limiting similarity or hierarchical competition, and rather noted the potential for trait plasticity and constraints on plasticity affecting performance in response to the competitive environment.