Halali Sridhar, Yapar Etka, Wheat Christopher W, Wahlberg Niklas, Gotthard Karl, Chazot Nicolas, Nylin Sören, Lehmann Philipp
Department of Biology, Lund University, Sweden.
Department of Zoology, Stockholm University, Stockholm, Sweden.
Evol Lett. 2024 Oct 18;9(1):125-136. doi: 10.1093/evlett/qrae054. eCollection 2025 Feb.
Quantifying the tempo and mode via modern phylogenetic comparative methods can provide key insights into how selection and constraints shape trait evolution on a macroevolutionary time scale. Here, we elucidate the evolution of hibernation (winter) diapause, a complex and defining life-history trait that allows temporal escape from harsh winters in temperate regions for many insects, including our model system, butterflies. Butterflies can diapause in all major life stages, and the availability of global-scale phylogenies makes them an ideal model system for studying diapause evolution. First, using a thorough literature survey, we scored the developmental stage of hibernation diapause (egg, larva, pupa, adult) vs. absence of diapause. We find that larval diapause is most common, while pupal, egg, and adult diapause are relatively rare. Next, we determined that the loss of diapause occurred at a much higher rate and that gains primarily occurred from the non-diapause state. While ancestral state estimation at deeper nodes remained uncertain, we found consistent patterns for some families and strong evidence for extensive convergence in diapause evolution. Contrary to expectations, we find no support for increased gain of diapause during the Eocene-Oligocene glaciation (~35 million years ago). Overall, the evolution of diapause in butterflies has a complex history, has evolved convergently, and has likely predated the major glaciation event consistent with the deep history of diapause evolution in insects. This study advances our understanding of the evolution of a complex and important life-history trait and establishes a macroevolutionary foundation for future studies on the ultimate and proximate basis of diapause evolution.
通过现代系统发育比较方法来量化节奏和模式，可以为在宏观进化时间尺度上选择和限制如何塑造性状进化提供关键见解。在这里，我们阐明了冬眠（冬季）滞育的进化，这是一种复杂且具有决定性的生活史性状，它使包括我们的模型系统蝴蝶在内的许多昆虫能够在温带地区暂时躲避严酷的冬季。蝴蝶在所有主要生命阶段都可以进入滞育状态，全球尺度系统发育树的可得性使其成为研究滞育进化的理想模型系统。首先，通过全面的文献调查，我们对冬眠滞育的发育阶段（卵、幼虫、蛹、成虫）与非滞育状态进行了评分。我们发现幼虫滞育最为常见，而蛹、卵和成虫滞育相对较少。接下来，我们确定滞育的丧失发生频率要高得多，而且获得主要是从非滞育状态开始的。虽然在更深节点的祖先状态估计仍然不确定，但我们发现了一些科的一致模式以及滞育进化中广泛趋同的有力证据。与预期相反，我们没有找到支持在始新世 - 渐新世冰川期（约3500万年前）滞育增加获得的证据。总体而言，蝴蝶滞育的进化有着复杂的历史，已经趋同进化，并且可能早于主要的冰川事件，这与昆虫滞育进化的悠久历史一致。这项研究推进了我们对一种复杂且重要的生活史性状进化的理解，并为未来关于滞育进化的终极和近因基础的研究奠定了宏观进化基础。
