Arendt J D
Department of Biology, University of California at Riverside, Riverside, CA, USA.
Heredity (Edinb). 2015 Oct;115(4):306-11. doi: 10.1038/hdy.2015.21. Epub 2015 Mar 25.
Phenotypic plasticity is thought to have a role in driving population establishment, local adaptation and speciation. However, dispersal plasticity has been underappreciated in this literature. Plasticity in the decision to disperse is taxonomically widespread and I provide examples for insects, molluscs, polychaetes, vertebrates and flowering plants. Theoretical work is limited but indicates an interaction between dispersal distance and plasticity in the decision to disperse. When dispersal is confined to adjacent patches, dispersal plasticity may enhance local adaptation over unconditional (non-plastic) dispersal. However, when dispersal distances are greater, plasticity in dispersal decisions strongly reduces the potential for local adaptation and population divergence. Upon dispersal, settlement may be random, biased but genetically determined, or biased but plastically determined. Theory shows that biased settlement of either type increases population divergence over random settlement. One model suggests that plasticity further enhances chances of speciation. However, there are many strategies for deciding on where to settle such as a best-of-N strategy, sequential sampling with a threshold for acceptance or matching with natal habitat. To date, these strategies do not seem to have been compared within a single model. Although we are just beginning to explore evolutionary effects of dispersal plasticity, it clearly has the potential to enhance as well as inhibit population divergence. Additional work should pay particular attention to dispersal distance and the strategy used to decide on where to settle.
表型可塑性被认为在推动种群建立、局部适应和物种形成方面发挥作用。然而，在这一文献中，扩散可塑性一直未得到充分重视。扩散决策的可塑性在分类学上广泛存在，我提供了昆虫、软体动物、多毛类动物、脊椎动物和开花植物的例子。理论研究有限，但表明扩散距离与扩散决策的可塑性之间存在相互作用。当扩散局限于相邻斑块时，扩散可塑性可能比无条件（非可塑性）扩散更能增强局部适应。然而，当扩散距离更大时，扩散决策的可塑性会大大降低局部适应和种群分化的潜力。扩散后，定居可能是随机的、有偏向但由基因决定的，或者有偏向但由可塑性决定的。理论表明，任何一种类型的偏向性定居都会比随机定居增加种群分化。一个模型表明，可塑性进一步增加了物种形成的机会。然而，决定定居地点有许多策略，如N中选优策略、带有接受阈值的顺序抽样或与出生地栖息地匹配。迄今为止，这些策略似乎尚未在单一模型中进行比较。尽管我们才刚刚开始探索扩散可塑性的进化影响，但它显然既有可能增强也有可能抑制种群分化。更多的研究应该特别关注扩散距离以及用于决定定居地点的策略。
