Maria Paniw, Hanna Serediuk

Insects play a crucial role in all ecosystems, and are increasingly exposed to higher in temperature extremes under climate change, which can have substantial effects on their abundances. However, the effects of temperature on changes in abundances or population fitness are filtered through differential responses of life-history components, such as survival, reproduction, and development, to their environment. Such differential responses, or trade-offs, have been widely studied in birds and mammals, but comparative studies on insects are largely lacking, limiting our understanding of key mechanisms that may buffer or exacerbate climate-change effects across insect species. Here, we performed a systematic literature review of the ecological studies of lacewings (Neuroptera), predatory insects that play a crucial role in ecosystem pest regulation, to investigate the impact of temperature on life-cycle dynamics across species. We found quantitative information, linking stage-specific survival, development, and reproduction to temperature variation, for 64 species from 39 locations. We then performed a metanalysis calculating sensitives to temperature across life-history processes for all publications. We found that developmental times consistently decreased with temperature for all species. Survival and reproduction however showed a weaker response to temperature, and temperature sensitivities varied substantially among species. After controlling for the effect of temperature on life-history processes, the latter covaried consistently across two main axes of variation related to instar and pupae development, suggesting the presence of life-history trade-offs. Our work provides new information that can help generalize life-history responses of insects to temperature, which can then expand comparative demographic and climate-change research. We also discuss important remaining knowledge gaps, such as a better assessment of adult survival and diapause.