Thermal fertility limits and their consequences in butterflies

Increasing temperatures, including increased frequency and severity of heatwaves, are impacting biodiversity distribution and abundance. Improved understanding of effects of increased warming is paramount.

This project aims to improve forecasting species’ responses to climate change by addressing current shortcomings in the understanding of species’ vulnerability and resilience.

Specifically, reproductive processes are typically more thermally sensitive than those causing death, yet most studies base their forecast of future responses on survival traits. This means forecasts may be too optimistic.

In contrast, forecasts typically ignore adaptive evolutionary processes that may provide resilience to climate change, meaning forecasts may be too pessimistic.

In this project, I address this conundrum using butterfly species to link experimental data on fertility and lethal limits, potential local adaptation, and field surveys on the ecological relevance of fertility limits.

These data are then applied to more sophisticated models that leverages long term monitoring data on European butterfly species’ distributions to test how thermal fertility limits alters forecasts to species’ responses to climate change.

This research links experimental results and natural population outcomes to deliver novel insights on climate change effects in an important insect group. Moreover, the innovative evolutionary ecology framework provides a roadmap to improve forecasts in other species.