Transitions between foot postures are associated with elevated rates of body size evolution in mammals.
Transitions between foot postures are associated with elevated rates of body size evolution in mammals.
复制标题
足部姿势之间的转变与哺乳动物体型进化速度的加快有关。
DOI：
10.1073/pnas.1814329116
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发表时间：
2019
影响因子：
11.1
通讯作者：
Kubo T
中科院分区：
文献类型：
--
作者：
Kubo T
陆生哺乳动物进化出了多种足部姿势：平足（plantigrady）、踮脚（diggrady）和有蹄（unguligrady）。虽然足部姿势对哺乳动物物种的生态和体型的重要性已被广泛认识，但其在哺乳动物系统发育中的进化轨迹及其对体型进化的影响尚未得到验证。采用贝叶斯系统发育方法，结合880种现存哺乳动物足部姿势的综合数据集，研究了相同姿势和姿势之间转换的足部姿势的进化史和体型进化速度。结果表明，哺乳动物的共同祖先是植足动物，并且主要发生在植足动物与数字化动物之间以及数字化动物与非植足动物之间的过渡。在plantigrady和digitalgrady以及digital和unguligrady之间的过渡阶段，体型进化速度显著提高，导致digitalgrade物种（~ 1 kg）和unguligrady物种（~ 78 kg）的体重比它们各自的祖先姿势[plantigrady （~ 0.75 kg）和digitalgrady]更大。我们的研究结果证明了足部姿势对哺乳动物体型进化的重要性，并对哺乳动物体型随着时间的推移而增加有影响。此外，我们强调了寻求整合形态功能和宏观进化方法的未来研究的前进方向。
Terrestrial mammals have evolved various foot postures: flat-footed (plantigrady), tiptoed (digitigrady), and hooved (unguligrady) postures. Although the importance of foot posture on ecology and body size of mammalian species has been widely recognized, its evolutionary trajectory and influence on body size evolution across mammalian phylogeny remain untested. Taking a Bayesian phylogenetic approach combined with a comprehensive dataset of foot postures in 880 extant mammalian species, we investigated the evolutionary history of foot postures and rates of body size evolution, within the same posture and at transitions between postures. Our results show that the common ancestor of mammals was plantigrade, and transitions predominantly occurred only between plantigrady and digitigrady and between digitigrady and unguligrady. At the transitions between plantigrady and digitigrady and between digitigrady and unguligrady, rates of body size evolution are significantly elevated leading to the larger body masses of digitigrade species (∼1 kg) and unguligrade species (∼78 kg) compared with their respective ancestral postures [plantigrady (∼0.75 kg) and digitigrady]. Our results demonstrate the importance of foot postures on mammalian body size evolution and have implications for mammalian body size increase through time. In addition, we highlight a way forward for future studies that seek to integrate morphofunctional and macroevolutionary approaches.