Although climate suitability is often thought to be the most important determinant of species ranges, non‐climate variables such as biotic interactions, dispersal abilities, and habitat quality may play equally important roles as range‐limiting factors. For some organisms, the constraints imposed by these non‐climate variables may explain their failure to establish in novel habitats that appear suitable with respect to climate...

Wild bees play indispensable ecological roles in many ecosystems, yet declines in many species have been documented in recent years. These declines have been linked to numerous anthropogenic pressures, including climate change, which can influence bee populations directly (i.e., via physiological mechanisms) and indirectly (e.g., through changes to floral resource quantity and quality). Widespread changes in the distributions...

Land use change threatens global biodiversity and compromises ecosystem functions, including pollination and food production. Reduced taxonomic α‐diversity is often reported under land use change, yet the impacts could be different at larger spatial scales (i.e., γ‐diversity), either due to reduced β‐diversity amplifying diversity loss or increased β‐diversity dampening diversity loss. Additionally, studies often focus on taxo...

Plants produce an array of defensive compounds with toxic or deterrent effects on insect herbivores. Pollen can contain relatively high concentrations of such defense compounds, but the causes and consequences of this enigmatic phenomenon remain mostly unknown. These compounds could potentially protect pollen against antagonists but could also reduce flower attractiveness to pollinators. We combined field observations of the p...

Specialist insect herbivores make up a substantial fraction of Earth's biodiversity; however, they exploit a minority of plant lineages. For instance, in the eastern United States and Canada, ~25% of bee species are pollen specialists, but they are hosted by a small fraction of the native, animal‐pollinated angiosperms in the region: Only 6% of plant genera and 3% of families support pollen‐specialist bees. It is unclear why s...

Evolutionary ecologists seek to explain the processes that maintain variation within populations. In plants, petal color variation can affect pollinator visitation, environmental tolerance, and herbivore deterrence. Variation in sexual organs may similarly affect plant performance. Within‐population variation in pollen color, as occurs in the eastern North American spring ephemeral Erythronium americanum , provides an excellen...

Warm temperatures are required for insect flight. Consequently, warming could benefit many high‐latitude and high‐altitude insects by increasing opportunities for foraging or oviposition. However, warming can also alter species interactions, including interactions with natural enemies, making the net effect of rising temperatures on population growth rate difficult to predict. We investigated the temperature‐dependence of nest...