stressors

Ecophysiology of locomotion and muscle function. Beyond locomotion per se, a significant part of the lab’s work asks how various biological and environmental stressors affect the physiological systems that make locomotion possible — particularly flight muscle function and metabolic performance. This line of research has its roots in our work on dragonflies (Libellula pulchella), where gut infection by parasitic gregarines was found to remodel flight muscle composition and function in ways that functionally mimic the effects of obesity in vertebrates — impairing the contractile machinery of what is arguably the most metabolically demanding tissue in the animal kingdom. This work established a broader framework the lab continues to build on: that stressors acting at the cellular and molecular level can have measurable and ecologically meaningful consequences for whole-animal locomotor performance.

We have since extended this framework across a range of taxa and stressor types. In migratory butterflies — monarchs (Danaus plexippus) and painted ladies (Vanessa cardui) — we have examined how exposure to neonicotinoid insecticides such as clothianidin affects flight performance, finding divergent effects across species that underscore the importance of studying stressor impacts in a comparative context (Cibotti et al., 2024). Related work has shown that clothianidin exposure also alters metabolic rates across life stages in monarchs, suggesting that the physiological consequences of pesticide exposure are not confined to adults capable of flight (Cibotti et al., 2025).

Diet and larval host plant identity add another layer: the milkweed species monarchs are reared on during development shapes their adult dispersal traits and free-flight energetics, with implications for how habitat degradation and host plant availability interact with migratory capacity (Pocius et al., 2022). Immune challenges represent yet another stressor of relevance — in bumble bees (Bombus impatiens), we have found that even non-pathogenic immune activation negatively affects thermal tolerance and chill coma recovery (Stewart & Schilder, 2026), pointing to energetic trade-offs between immune function and the physiological systems that sustain thermoregulation and locomotion. Taken together, this body of work reflects a view of animal performance as an integrative outcome — one that is continuously shaped by the interplay of genetic, nutritional, immunological, and environmental factors.