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Meta‐analyses have become a valuable tool with which to synthesize effects across studies, but in ecology and evolution, they are often characterized by high heterogeneity, where effect sizes vary between studies. Much of this heterogeneity can be attributed to species‐specific differences in responses to predictor variables. Here, we aimed to incorporate a novel trait‐based approach to explain species‐specific differences in a meta‐analysis by testing the ability of morphological traits to explain why the effectiveness of flight‐intercept trap design varies according to beetle species, a critical issue in forest pest management. An existing morphological trait database for forest beetles was supplemented, providing trait data for 97 species, while data from a previous meta‐analysis on capture rates of bark or woodboring beetles according to different trap designs were updated. We combined these sources by including nine morphological traits as moderators in meta‐analysis models, for five different components of trap design. Traits were selected based on theoretical hypotheses relating to beetle movement, maneuverability, and sensory perception. We compared the performance of morphological traits as moderators versus guild, taxonomic family, and null meta‐analysis models. Morphological traits for the effect of trap type (panel vs. multiple‐funnel) on beetle capture rates improved model fit (AICc), reduced within‐study variance (σ2), and explained more variation (McFadden's pseudo‐R2) compared with null, guild, and taxonomic family models. For example, morphological trait models explained 10% more of the variance (pseudo‐R2) when compared with a null model. However, using traits was less informative to explain how detailed elements of trap design such as surface treatment and color influence capture rates. The reduction of within‐study variance when accounting for morphological traits demonstrates their potential value for explaining species‐specific differences. Morphological traits associated with flight efficiency, maneuverability, and eye size were particularly informative for explaining the effectiveness of trap type. This could lead to improved predictability of optimal trap design according to species. Therefore, morphological traits could be a valuable tool for understanding species‐specific differences in community ecology, but other causes of heterogeneity across studies, such as forest type and structure, require further investigation. [ABSTRACT FROM AUTHOR]

Fluctuating asymmetry (FA) is hypothesized to be a useful predictor of population canalization, especially for organisms at risk from environmental change.Identification of traits that meet statistical criteria as FA measures remains a challenge.Here, a laboratory experiment subjected immature butterflies (Vanessa cardui) to diet and temperature conditions of varying stress levels. Variation in dietary macronutrient ratio (protein: carbohydrate) and rearing temperature (optimal: 25°C; elevated: 32°C) was introduced as stressors. Temperature and nutrition are key variables influencing ectotherm growth and fitness and so are likely to be important stressors that influence FA.Individuals subjected to stressful conditions were predicted to show elevated FA of three wing size traits, as well as increased mortality and decreased adult body size.Trait FA did not vary across treatments. Instead, treatment levels impacted viability: The combined incidence of pupal death and expression of significant wing malformations increased in treatment levels designated as stressful. Variation in adult dry mass also reflected predicted stress levels. Results suggest that individuals predicted to display increased FA either died or displayed gross developmental aberrations.This experiment illustrates important constraints on the investigation of FA, including selection of appropriate traits and identification of appropriate levels of stressors to avoid elevated mortality. The latter concern brings into question the utility of FA as an indicator of stress in vulnerable, natural populations, where stress levels cannot be controlled, and mortality and fitness effects are often not quantifiable. [ABSTRACT FROM AUTHOR]

Sharpshooters (Hemiptera: Cicadellidae: Cicadellinae) and spittlebugs (Hemiptera: Aphrophoridae: Aphrophorinae) have a worldwide distribution and are often associated with many crops. Because the geographic range of sharpshooters and spittlebugs often overlaps with the range of the plant pathogenic bacterium Xylella fastidiosa, the importance of these groups of insects in spreading X. fastidiosa rises to the level of a major socioeconomic problem. Managing diseases caused by X. fastidiosa is challenging for several reasons. First, multiple sequence types of the pathogen have been identified, with sequence type affecting host plant specificity. Second, multiple vector species may be present in an agroecosystem, and the host range of vector species is often broad. Although multiple vector control options such as biological, chemical, physical and cultural controls have been described, disease control programs must take into account biological and ecological parameters of locally dominant X. fastidiosa sequence types and vector species to develop suitable control strategies. Our review demonstrates how fundamental principles of vector reproductive biology, behaviour, nutrition and population and community ecology have influenced research on insect vectors and provides insights into priority research areas. [ABSTRACT FROM AUTHOR]

We examined dietary self-selection and rules of compromise for protein (P) and digestible carbohydrate (C) intake by fifth-instar Vanessa cardui L. ( Lepidoptera: Nymphalidae: Nymphalini). We presented six fat-free diet pairs to larvae in a choice trial to determine the 'intake target'. In addition, we fed larvae seven fat-free single diets differing in dietary nutrient ratio in no-choice trials to determine the rules of compromise they exhibit when constrained to a singular, sub-optimal dietary source. In choice trials, caterpillars regulated nutrient intake to a ratio of 1 protein to 1.09 carbohydrate (1P:1.09C), exhibiting tighter regulation of protein than of carbohydrate. Furthermore, larvae from different diet pair treatments did not differ in pupal mass or stadium duration. In no-choice experiments, larvae reduced consumption on increasingly protein-biased diets and increased consumption on increasingly carbohydrate-biased diets, relative to a 1P:1C ratio diet. Differences in carbohydrate consumption were much greater between no-choice treatments than differences in protein consumption. Dietary nutrient ratio affected pupal mass when accounting for initial larval mass. Pupal mass decreased as nutrient ratio was shifted off of 1P:1C, but to a greater extent when the ratio was skewed toward carbohydrate. Stadium duration increased as nutrient ratio diverged from 1P:1C, being more pronounced when shifted toward carbohydrate than toward protein. Regulation to near 1P:1C is consistent with results found for other Lepidoptera, and the rule of compromise exhibited by V. cardui is consistent with that expected for a generalist herbivore. [ABSTRACT FROM AUTHOR]

Predicting changes in potential habitat for endangered species as a result of global warming requires considering more than future climate conditions; it is also necessary to evaluate biotic associations. Most distribution models predicting species responses to climate change include climate variables and occasionally topographic and edaphic parameters, rarely are biotic interactions included. Here, we incorporate biotic interactions into niche models to predict suitable habitat for species under altered climates. We constructed and evaluated niche models for an endangered butterfly and a threatened bird species, both are habitat specialists restricted to semiarid shrublands of southern California. To incorporate their dependency on shrubs, we first developed climate-based niche models for shrubland vegetation and individual shrub species. We also developed models for the butterfly's larval host plants. Outputs from these models were included in the environmental variable dataset used to create butterfly and bird niche models. For both animal species, abiotic–biotic models outperformed the climate-only model, with climate-only models over-predicting suitable habitat under current climate conditions. We used the climate-only and abiotic–biotic models to calculate amounts of suitable habitat under altered climates and to evaluate species' sensitivities to climate change. We varied temperature (+0.6, +1.7, and +2.8 °C) and precipitation (50%, 90%, 100%, 110%, and 150%) relative to current climate averages and within ranges predicted by global climate change models. Suitable habitat for each species was reduced at all levels of temperature increase. Both species were sensitive to precipitation changes, particularly increases. Under altered climates, including biotic variables reduced habitat by 68–100% relative to the climate-only model. To design reserve systems conserving sensitive species under global warming, it is important to consider biotic interactions, particularly for habitat specialists and species with strong dependencies on other species. [ABSTRACT FROM AUTHOR]

Compares the aboveground architecture and leaf traits in Encelia farinosa in a coastal and desert environment. Variation among offspring grown in common gardens; Differences in herbivory; Water-use efficiency; Photosynthetic rate.

Indirect interactions among native and invasive species are notoriously difficult to predict. Here, we apply theory from trait‐mediated indirect effects and plant–insect interactions to explain the outcomes of multiple invader interactions. The present study investigates the roles of herbivore preference and plant ontogeny in mediating associational effects among a southern California native shrub, Atriplex canescens, an invasive annual forb, Brassica tournefortii, and an invasive stink bug, Bagrada hilaris. Ba. hilaris have been observed to form dense aggregations on A. canescens in late spring following senescence of Br. tournefortii, with subsequent increased mortality of A. canescens. A manipulative experiment found Ba. hilaris recruited to A. canescens in approximately 70 times greater numbers when neighbored by Br. tournefortii than when alone. Ba. hilaris nymph production, while minimized experimentally, occurred only on Br. tournefortii, suggesting A. canescens is not of sufficient quality for Ba. hilaris reproduction. In greenhouse preference trials, Ba. hilaris exhibited an overall preference for Br. tournefortii over A. canescens; however, the magnitude of preference depended on ontogenetic stage of Br. tournefortii. Overall, our results suggest significant potential for associational susceptibility mediated by a combination of Ba. hilaris preference for reproductive Br. tournefortii, substantial aggregation of Ba. hilaris onto Br. tournefortii, and a marked decline in Ba. hilaris preference for Br. tournefortii with advancing ontogeny—triggering spillover onto neighboring plants. Our results demonstrate an important role for multiple invaders and phenologically driven trait changes in mediating associational susceptibility. [ABSTRACT FROM AUTHOR]