Institut für Populationsgenetik, Vetmeduni Vienna, A-1210 Vienna, Austria.
Q Rev Biol. 2013 Sep;88(3):185-218. doi: 10.1086/671484.
Here we discuss life-history evolution from the perspective of adaptive phenotypic plasticity, with a focus on polyphenisms for somatic maintenance and survival. Polyphenisms are adaptive discrete alternative phenotypes that develop in response to changes in the environment. We suggest that dauer larval diapause and its associated adult phenotypes in the nematode (Caenorhabditis elegans), reproductive dormancy in the fruit fly (Drosophila melanogaster) and other insects, and the worker castes of the honey bee (Apis mellifera) are examples of what may be viewed as the polyphenic regulation of somatic maintenance and survival. In these and other cases, the same genotype can--depending upon its environment--express either of two alternative sets of life-history phenotypes that differ markedly with respect to somatic maintenance, survival ability, and thus life span. This plastic modulation of somatic maintenance and survival has traditionally been underappreciated by researchers working on aging and life history. We review the current evidence for such adaptive life-history switches and their molecular regulation and suggest that they are caused by temporally and/or spatially varying, stressful environments that impose diversifying selection, thereby favoring the evolution of plasticity of somatic maintenance and survival under strong regulatory control. By considering somatic maintenance and survivorship from the perspective of adaptive life-history switches, we may gain novel insights into the mechanisms and evolution of aging.
在这里，我们从适应表型可塑性的角度讨论生活史进化，重点关注与躯体维持和生存相关的多态现象。多态现象是指适应性离散替代表型，它们是对环境变化的反应而发展起来的。我们认为，线虫（秀丽隐杆线虫）中的 dauer 幼虫休眠及其相关的成虫表型、果蝇（黑腹果蝇）和其他昆虫的生殖休眠，以及蜜蜂（Apis mellifera）的工蜂等级，都是可能被视为躯体维持和生存的多态性调节的例子。在这些和其他情况下，同一基因型可以——取决于其环境——表达两种截然不同的生活史表型中的任意一种，这两种表型在躯体维持、生存能力方面存在显著差异，因此寿命也存在差异。这种对躯体维持和生存的可塑性调节在研究衰老和生活史的研究人员中一直被低估。我们回顾了目前关于这种适应性生活史转变及其分子调控的证据，并提出它们是由时间和/或空间变化的、有压力的环境引起的，这些环境施加了多样化选择，从而有利于在强烈的监管控制下进化出躯体维持和生存的可塑性。通过从适应性生活史转变的角度考虑躯体维持和生存，我们可能会对衰老的机制和进化获得新的认识。
