Temperature effects on reproductive and life-history traits in Drosophila (Diptera: Drosophilidae): a systematic map
Understanding how rising and fluctuating temperatures affect fitness-related traits is critical for predicting the biological consequences of climate change. Ectotherms like Drosophila (Diptera: Drosophilidae) are particularly vulnerable due to their physiological dependence of environmental temperature. While many studies have focused on thermal tolerance and survival, sub-lethal temperature effects on reproductive and life-history traits remain understudied despite their ecological and evolutionary relevance. This study presents a systematic review of 288 articles that assessed the temperature effects on six reproductive traits: fertility, fecundity, mating traits, egg hatching, gamete and gonad traits and four life-history traits: longevity, mortality, viability and development time in Drosophila species. The results reveal an increase in publications since 1995 and 45 different species employed, with Drosophila melanogaster being the dominant model organism. Heat stress was more frequently studied than cold stress, and most experiments involved adult life-stages under constant temperatures. Fecundity and longevity were the most frequently measured traits. Most studies applied constant temperature stress and long-term exposure and few studies examined thermal pre-treatments or artificial selection to evaluate adaptive responses. The data reveals geographical and taxonomic biases, with limited representation from tropical regions and non-model species. This comprehensive dataset underscores the need for broader species coverage, inclusion of variable thermal regimes, and consideration of sex- and stage-specific sensitivities. This study provides a valuable source to guide future studies on thermal adaptation and emphasizes the importance of integrating physiological, behavioral, and ecological data to better predict the response of Drosophila and other ectotherms under thermal stress.