Marine Biology and Ecology Research Centre, School of Marine Science and Engineering, Plymouth University, Drake Circus, Plymouth, UK.
Evol Dev. 2011 Nov-Dec;13(6):542-8. doi: 10.1111/j.1525-142X.2011.00510.x.
Heterochrony, altered developmental timing between ancestors and their descendents, has been proposed as a pervasive evolutionary feature and recent analytical approaches have confirmed its existence as an evolutionary pattern. Yet, the mechanistic basis for heterochrony remains unclear and, in particular, whether intraspecific variation in the timing of developmental events generates, or has the potential to generate, future between-species differences. Here we make a key step in linking heterochrony at the inter- and intraspecific level by reporting an association between interindividual variation in both the absolute and relative timing (position within the sequence of developmental events) of key embryonic developmental events and genetic distance for the pond snail, Radix balthica. We report significant differences in the genetic distance of individuals exhibiting different levels of dissimilarity in their absolute and relative timing of developmental events such as spinning activity, eyespot formation, heart ontogeny, and hatching. This relationship between genetic and developmental dissimilarity is consistent with there being a genetic basis for variation in developmental timing and so suggests that intraspecific heterochrony could provide the raw material for natural selection to produce speciation.
时移进化，即祖先与其后代之间发育时间的改变，被认为是一种普遍的进化特征，最近的分析方法也证实了它作为一种进化模式的存在。然而，时移进化的机制基础仍不清楚，特别是在发育事件时间上的种内变异是否产生或有可能产生未来种间差异。在这里，我们通过报告关键胚胎发育事件的绝对和相对时间（在发育事件序列中的位置）的个体间变异与池塘蜗牛 Radix balthica 的遗传距离之间的关联，在连接种间和种内时移进化方面迈出了关键一步。我们报告了在旋转活动、眼斑形成、心脏发生和孵化等发育事件的绝对和相对时间上表现出不同程度相似性的个体之间的遗传距离存在显著差异。这种遗传和发育差异之间的关系表明，发育时间的变化存在遗传基础，因此表明种内时移进化可能为自然选择产生物种形成提供了原材料。
