Constraints on Mammalian forelimb development: insights from developmental disparity.
Constraints on Mammalian forelimb development: insights from developmental disparity.
复制标题
哺乳动物前肢发育的限制：发育差异的见解。
DOI：
10.1111/evo.12204
复制
发表时间：
2013
期刊：
影响因子：
--
通讯作者：
Sears,KarenE
中科院分区：
文献类型：
--
作者：
Ross,Darcy;Marcot,JonathanD;Betteridge,KeithJ;Nascone-Yoder,Nanette;Bailey,CScott;Sears,KarenE
四足动物的肢体发育已经被广泛研究了几十年，但在这个过程中发育限制的强度和作用仍然没有得到解决。哺乳动物表现出特别广泛的肢体形态与各种运动模式和行为，提供了一个有用的系统，用于识别时期的发展限制和保守的发展机制或形态。在这项研究中，地标为基础的几何形态测量学被用来调查的水平和模式的形态多样性（差距）之间的发展前肢的四种哺乳动物具有不同的肢体形态：小鼠，负鼠，马，猪。结果表明，从肢脊出现到芽期，这些物种前肢间的差异略有减小或保持不变，从桨状到组织退化阶段，差异急剧增大。未发现早熟负鼠肢体表现出的异时性驱动这些形态差异模式，这表明肢体发育中期的低差异（例如，桨状阶段）是由肢体内操作的过程驱动的，并且可能不是胚胎范围限制的结果。
Tetrapod limb development has been studied extensively for decades, yet the strength and role of developmental constraints in this process remains unresolved. Mammals exhibit a particularly wide array of limb morphologies associated with various locomotion modes and behaviors, providing a useful system for identifying periods of developmental constraint and conserved developmental mechanisms or morphologies. In this study, landmark-based geometric morphometrics are used to investigate levels and patterns of morphological diversity (disparity) among the developing forelimbs of four mammals with diverse limb morphologies: mice, opossums, horses, and pigs. Results indicate that disparity among the forelimbs of these species slightly decreases or stays the same from the appearance of the limb ridge to the bud stage, and increases dramatically from the paddle through tissue regression stages. Heterochrony exhibited by the precocial opossum limb was not found to drive these patterns of morphological disparity, suggesting that the low disparity of the middle stages of limb development (e.g., paddle stage) is driven by processes operating within the limb and is likely not a result of embryo-wide constraint.