Anthropogenization exacerbates global warming impact on dragonfly phenology

Climate change and human perturbation could exert an interactive effect on species life history and exacerbate their biological responses. Here, we show that the impact of global warming on the phenology of 37 species of odonates in the British Isle during 1980-2012 was stronger in areas with high human influence. This pattern was consistent across a geographic gradient, phylogeny, and functional groups. To understand the mechanism underlying this pattern, we analyzed the spatial variation in thermal regimes and found that areas with high human influence were warmer (thermal heat island). Using the thermal performance curve, we show that species’ non-linear response to temperature explains their differential phenological responses across a gradient of human impact, such that warmer anthropogenic areas heighten the sensitivity of species to climate warming. These results suggest that the climate-human interaction should be considered in climate change biology to explain and predict spatial variation in biotic response.