Feeling the heat: how metabolic physiology drives vulnerability of insects to ongoing winter warming

Energy metabolism during winter resting stages is usually heavily suppressed, and a major determinant of fitness in animals living in seasonal environments.

Our insight into the physiological mechanisms regulating metabolic suppression are still poor, and thus predicting consequences of ongoing winter warming is difficult, especially for ectothermic organisms, whose body temperature directly tracks that of the environment.

Recent studies suggest major roles for mitochondria, the ATP-regenerating “power plants” of most eukaryotic cells, in regulating winter metabolism, and the current proposal seeks to clarify the role mitochondria play in energy metabolism during winter in insects.

We will use a comparative and integrative approach to study whole organism and organelle metabolism across several ecological contrasts in the laboratory and using modelling approaches.

Most importantly, we will study population-dependent variation in metabolic performance and underlying genes in insect species that overwinter in different life-stages, to ask if populations across the chosen ecological contrasts show local adaptation in winter energetics.

This project will clarify longstanding questions regarding the physiology and evolution of metabolically suppressed states, but will also specifically work to generate relevant energetic models that predict vulnerabilities of insect populations (including important pollinators, agricultural pests and disease vectors) to winter warming.