Behavioural and physiological responses to thermal stress in a social spider

Temperature is one of the primary environmental drivers distribution species, and particularly high temperatures challenge physiological processes by disruption cellular homoeostasis. This exerts selection on organisms to maintain homoeostasis adaptive and/or behavioural responses. The social spider Stegodyphus dumicola occurs across several climate zones in Southern Africa, populations experience variable temperatures, suggesting a wide temperature niche, or alternatively that respond with plastic locally adapted responses temperature. Using common garden design, we investigated complementary heat (behavioural thermoregulation cuticle wax composition) individuals from warmer cooler locations. spiders exhibited higher tolerance than most ectotherms (CTmax almost 49?), locations showing highest tolerance. Analyses revealed chemical compositions consistent melting (e.g. increased chain length lower occurrence branching) therefore improved waterproofing originating acclimated at temperature, as expected if local drives changes composition improve waterproofing. clear escape response increasing kept acclimation threshold which this behaviour was triggered, under natural selection. Our study provides evidence both adaptation phenotypic plasticity traits relating Population differences trait expression suggest different thermal environments, plastically adjust cooling changes. Bogert effect predicts may relax for adaptations. instead suggests synergistic effects shape biology species. Local allows existence zones. Additionally, enables rapid short-term fluctuations within niche. We show act concert A free Plain Language Summary can be found Supporting Information article.