Merckx Thomas, Nielsen Matthew E, Kankaanpää Tuomas, Kadlec Tomáš, Yazdanian Mahtab, Kivelä Sami M
WILD, Biology Department Vrije Universiteit Brussel Brussels Belgium.
Ecology and Genetics Research Unit University of Oulu Oulu Finland.
Evol Appl. 2023 Dec 26;17(1):e13636. doi: 10.1111/eva.13636. eCollection 2024 Jan.
Urbanization and its urban-heat-island effect (UHI) have expanding footprints worldwide. The UHI means that urban habitats experience a higher mean and more frequent extreme high temperatures than rural habitats, impacting the ontogeny and resilience of urban biodiversity. However, many organisms occupy different microhabitats during different life stages and thus may experience the UHI differently across their development. While evolutionary changes in heat tolerance in line with the UHI have been demonstrated, it is unknown whether such evolutionary responses can vary across development. Here, using common-garden-reared moths from urban and rural populations from three European countries, we tested for urban evolution of heat shock tolerance in two life stages: larvae and adults. Our results indicate widespread urban evolution of increased heat tolerance in the adult stage only, suggesting that the UHI may be a stronger selective agent in adults. We also found that the difference in heat tolerance between urban and rural populations was similar to the difference between Mid- and North-European regions, suggesting similarity between adaptation to the UHI and natural, latitudinal temperature variation. Our observations incentivize further research to quantify the impact of these UHI adaptations on fitness during urbanization and climate change, and to check whether life-stage-specific adaptations in heat tolerance are typical of other ectothermic species that manage to survive in urbanized settings.
城市化及其城市热岛效应（UHI）在全球的影响范围不断扩大。城市热岛效应意味着城市栖息地的平均温度更高，极端高温出现得更频繁，这对城市生物多样性的个体发育和恢复力产生影响。然而，许多生物在不同的生命阶段占据不同的微生境，因此在其发育过程中对城市热岛效应的感受可能不同。虽然已经证明了与城市热岛效应相关的耐热性进化变化，但尚不清楚这种进化反应在整个发育过程中是否会有所不同。在这里，我们使用来自三个欧洲国家城市和农村种群的在共同花园中饲养的蛾类，测试了幼虫和成虫这两个生命阶段对热休克耐受性的城市进化情况。我们的结果表明，仅在成虫阶段存在广泛的城市耐热性进化增强现象，这表明城市热岛效应可能对成虫是更强的选择因素。我们还发现，城市和农村种群之间的耐热性差异与中欧和北欧地区之间的差异相似，这表明对城市热岛效应的适应与自然的纬度温度变化之间具有相似性。我们的观察结果促使进一步开展研究，以量化这些对城市热岛效应的适应在城市化和气候变化期间对适应性的影响，并检查耐热性的特定生命阶段适应是否是其他在城市化环境中生存的变温物种的典型特征。
