大多数,如果不是全部,生物体具有直接响应环境变化而改变其表型的能力,一种称为表型可塑性的现象。选择可以打破这种环境敏感性,然而,并通过称为遗传同化的过程使以前环境诱导的性状进化为固定。本质上,遗传同化可以被视为以前是环境敏感性状的环境稳健性的进化。因为遗传同化长期以来一直被认为在表型新颖性甚至新物种的起源中起着关键作用,识别和表征遗传同化背后的近似机制可能会增进我们对新性状和物种如何进化的基本理解。
这篇综述首先讨论了表型可塑性的进化,其次是遗传同化,可能会促进新性状的起源,并可能促进燃料形态和适应性辐射。然后简要考虑了遗传同化在进化创新和多样化中的证据。接下来,表型可塑性的潜在原因一般和遗传同化特别是在遗传检查,描述了可以提高我们对这些机制的理解的分子和生理水平以及方法。审查最后概述了未来工作的主要挑战。
识别和表征表型可塑性和遗传同化中涉及的近似机制有望帮助推进我们对进化创新和多样化的基本理解。
Most, if not all, organisms possess the ability to alter their phenotype in direct response to changes in their environment, a phenomenon known as phenotypic plasticity. Selection can break this environmental sensitivity, however, and cause a formerly environmentally induced trait to evolve to become fixed through a process called genetic assimilation. Essentially, genetic assimilation can be viewed as the evolution of environmental robustness in what was formerly an environmentally sensitive trait. Because genetic assimilation has long been suggested to play a key role in the origins of phenotypic novelty and possibly even new species, identifying and characterizing the proximate mechanisms that underlie genetic assimilation may advance our basic understanding of how novel traits and species evolve.
This
review begins by discussing how the evolution of phenotypic plasticity, followed by genetic assimilation, might promote the origins of new traits and possibly fuel speciation and adaptive radiation. The evidence implicating genetic assimilation in evolutionary innovation and diversification is then briefly considered. Next, the potential causes of phenotypic plasticity generally and genetic assimilation specifically are examined at the genetic, molecular and physiological levels and approaches that can improve our understanding of these mechanisms are described. The
review concludes by outlining major challenges for future work.
Identifying and characterizing the proximate mechanisms involved in phenotypic plasticity and genetic assimilation promises to help advance our basic understanding of evolutionary innovation and diversification.