Department of Organismal and Environmental Biology, Christopher Newport University, Newport News, VA, 23606, USA.
Sci Rep. 2022 May 19;12(1):8474. doi: 10.1038/s41598-022-12300-7.
Sexual selection is considered the primary driver of morph turnover in many color polymorphic taxa, yet the potential for other factors (like climate) to contribute to polymorphism maintenance and evolution remains unclear. Appreciation for a role of environmental conditions in the maintenance and evolution of color polymorphisms has grown in recent years, generating evidence suggesting that color morphs linked to sexual selection may also diverge in climate sensitivity. Focusing on the three color components contributing to the male tree lizard (Urosaurus ornatus) color morphs, I reveal a marked concordance between patterns of turnover over space and time, with a general affinity of orange- and yellow-colored males to hotter, more variable conditions, and blue colored males to wetter, cooler conditions. An assessment of long-term turnover in the blue color component in response to recent climate change over the past 60 years reinforces these findings. Overall, behavioral asymmetries attributed to sexual selection likely expose competing morphs to divergent environmental conditions in heterogeneous habitats, creating opportunity for natural selection to shape climate sensitivities that also drive turnover in morph color composition. Ultimately, these processes may favor stark asymmetries in morph persistence over the coming decades.
性选择被认为是许多颜色多态类群形态转换的主要驱动因素,但其他因素(如气候)对多态性维持和进化的潜在贡献仍不清楚。近年来,人们越来越认识到环境条件在维持和进化颜色多态性方面的作用,这一认识产生了一些证据,表明与性选择相关的颜色形态可能在气候敏感性方面也存在差异。本研究聚焦于导致雄性树蜥(Urosaurus ornatus)颜色形态的三个颜色组成部分,揭示了空间和时间上形态转换模式之间的明显一致性,橙色和黄色雄性蜥蜴倾向于更热、更不稳定的条件,而蓝色雄性蜥蜴则倾向于更潮湿、更凉爽的条件。对过去 60 年来蓝色颜色成分对近期气候变化的长期转换的评估加强了这些发现。总的来说,性选择导致的行为不对称可能使竞争形态暴露在异质栖息地的不同环境条件下,为自然选择提供了机会,从而塑造出对形态颜色组成转换也有影响的气候敏感性。最终,这些过程可能会导致在未来几十年中形态持久性的明显不对称。