期刊论文详细信息
Journal of biosciences
Limb, tooth, beak: Three modes of development and evolutionary innovation of form
Stuart A Newman22  Marta Linde-Medina1 21 
[1] University of Manchester, UK$$;New York Medical College, USA$$
关键词: Evo-devo;    morphogenesis;    morphological novelty;    saltation;   
DOI  :  
来源: Indian Academy of Sciences
PDF
【 摘 要 】

The standard model of evolutionary change of form, deriving from Darwin’s theory via the Modern Synthesis, assumes a gradualistic reshaping of anatomical structures, with major changes only occurring by many cycles of natural selection for marginal adaptive advantage. This model, with its assertion that a single mechanism underlies both micro- and macroevolutionary change, contains an implicit notion of development which is only applicable in some cases. Here we compare the embryological processes that shape the vertebrate limb bud, the mammalian tooth and the avian beak. The implied notion of development in the standard evolutionary picture is met only in the case of the vertebrate limb, a single-primordium organ with morphostatic shaping, in which cells rearrange in response to signalling centres which are essentially unchanged by cell movement. In the case of the tooth, a single-primordium organ with morphodynamic shaping in which the strengths and relationships between signalling centres is influenced by the cell and tissue movements they induce, and the beak, in which the final form is influenced by the collision and rearrangement of multiple tissue primordia, abrupt appearance of qualitatively different forms (i.e. morphological novelties) can occur with small changes in system parameters induced by a genetic change, or by an environmental factor whose effects can be subsequently canalized genetically. Bringing developmental mechanisms and, specifically, the material properties of tissues as excitable media into the evolutionary picture, demonstrates that gradualistic change for incremental adaptive advantage is only one of the possible modes of morphological evolution.

【 授权许可】

Unknown   

【 预 览 】
附件列表
Files Size Format View
RO201912040495302ZK.pdf 1619KB PDF download
  文献评价指标  
  下载次数:7次 浏览次数:28次