Cole Benjamin, Vasudeva Ramakrishnan, Dragoi Kay, Hibble Josie, King James, Maklakov Alexei A, Chapman Tracey, Gage Matthew J G
School of Biological Sciences , University of East Anglia, Norwich, NR4 7TJ, UK.
Faculty of Environment, Science and Economy, Ecology and Conservation, University of Exeter, Penryn, Cornwall, TR10 9FE, UK.
J Exp Biol. 2025 Aug 1;228(15). doi: 10.1242/jeb.250555.
Heatwaves are becoming more common and severe. Previous work has highlighted male insects as being particularly vulnerable to multi-day continuous heatwaves, yet our understanding of short duration heatwave impacts on insects is limited. Here, we assessed the impacts of short, simulated heatwave exposures (2, 5 and 10 h) using ecologically relevant temperatures (42, 44, 46, 48 and 50°C) on survival, reproductive output, testes volume and sperm length in Tribolium castaneum. We show that reproductive output is compromised at lower temperatures than survival, especially during the shortest heatwaves, supporting the notion that thermal fertility limits are lower than thermal viability limits. Furthermore, testes volume was reduced by 40% after a 10 h exposure at 42°C and sperm length decreased by 2.7% after an exposure of 42°C for just 2 h. This highlights that even short heat exposure can impact male fertility and reproductive trait morphology at temperatures below viability limits.
热浪正变得愈发常见和严重。先前的研究强调雄性昆虫特别容易受到多日持续热浪的影响，然而我们对短期热浪对昆虫影响的了解有限。在此，我们使用与生态相关的温度（42、44、46、48和50°C）评估了短期模拟热浪暴露（2、5和10小时）对赤拟谷盗生存、繁殖产出、睾丸体积和精子长度的影响。我们发现，繁殖产出在比生存更低的温度下就会受到影响，尤其是在最短的热浪期间，这支持了热生育极限低于热生存极限的观点。此外，在42°C下暴露10小时后，睾丸体积减少了40%，而在42°C下仅暴露2小时后，精子长度就减少了2.7%。这突出表明，即使是短暂的热暴露也会在低于生存极限的温度下影响雄性生育能力和生殖性状形态。
