The evolution of gestation length in eutherian mammals.
The evolution of gestation length in eutherian mammals.
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真兽类哺乳动物妊娠长度的演变。
DOI：
10.1101/2023.10.22.563491
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发表时间：
2023
期刊：
影响因子：
--
通讯作者：
Rokas,Antonis
中科院分区：
文献类型：
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作者：
Danis,Thodoris;Rokas,Antonis
真兽类哺乳动物在妊娠长度上表现出相当大的差异，这在传统上被认为与其他特征的变化有关，包括体重和寿命。为了了解孕长变化，包括它与体重和寿命变化的关系，如何在哺乳动物进化过程中发生变化，我们对845个代表性现存物种进行了系统发育分析。我们发现，在哺乳动物中，妊娠长度与体重和寿命之间的关系是否以及有多大程度上都有很大的不同。例如，在翼手目和鲸类中，妊娠长度与寿命或身体质量无关，但在食肉动物中只与身体质量密切相关。我们还在哺乳动物系统发育过程中发现了52个孕长变异的进化转变，当我们联合考虑所有三个特征的变异时，发现了14个转变；6个转变是共享的。值得注意的是，这两个变化都是正的，分别发生在鲸目和针足纲的根部，与这些分支向海洋环境的过渡相吻合，而翼手目的根部发生了负的变化，与该分支的飞行进化相吻合。这些结果表明，妊娠长度和其他两个特征之间的关系在哺乳动物的系统发育中有很大的不同。
Eutherian mammals exhibit considerable variation in their gestation lengths, which has traditionally been linked to variation in other traits, including body mass and lifespan. To understand how gestation length variation, including its association with body mass and lifespan variation, changed over mammalian evolution, we conducted phylogeny-informed analyses of 845 representative extant species. We found that gestation length substantially differed in both whether and how strongly it was associated with body mass and lifespan across mammals. For example, gestation length was not associated with lifespan or body mass in Chiroptera and Cetacea but was strongly associated only with body mass in Carnivora. We also identified 52 evolutionary shifts in gestation length variation across the mammal phylogeny and 14 shifts when we jointly considered variation of all three traits; six shifts were shared. Notably, two of these shifts, both positive, occurred at the roots of Cetacea and Pinnipedia, respectively, coinciding with the transition of these clades to the marine environment, whereas a negative shift occurred at the root of Chiroptera, coinciding with the evolution of flight in this clade. These results suggest that the relationship between gestation length and the two other traits has varied substantially across mammalian phylogeny.