美国匹兹堡大学Yusan Yang等研究人发现印记为物种形成奠定了基础。2019年10月2日，《自然》杂志在线发表了这项成果。
研究人员证明了印记除了可以调解女性伴侣的喜好外，还可以塑造男性与男性侵略中的偏好。这些偏好可以与自然选择类似地起作用，以维持性状和伴侣偏好的变化，从而促进完全由性选择驱动的生殖隔离。通过一项交叉寄养研究，研究人员发现，雄性和雌性草莓箭毒蛙（Oophaga pumilio）都会在着色上留下印记，而这种交配性状最近在该物种中迅速发散。异养的雌性更喜欢与养母同色的伴侣，异养的雄性对拥有异养本色的竞争对手更具攻击性。
研究人员还使用一个简单的种群遗传模型来证明，当通过父母的印记形成男性侵略偏好和女性伴侣偏好时，仅凭性别选择就可以稳定同胞多态性，以及加强导致性格与偏好的关联进行行为生殖隔离。
这项研究提供了在两栖动物上留下印记的证据，并表明这种很少考虑的竞争对手和有性印记的组合可以减少具有不同交配特性的个体之间的基因流，从而为通过性选择进行物种形成奠定了基础。
据介绍，性印记是一种现象，后代会学习父母的特征，然后将其用作自己的配偶偏好的榜样，这种现象会在物种之间产生生殖屏障。当印记的目标是区分年轻世系之间的交配特征时，印记的偏好可能有助于行为隔离并促进物种形成。但是，在大多数通过性别选择进行物种形成的模型中，也需要不同的自然选择。后者的作用是产生和维持一个或多个性选择特征和作用于它们的交配偏好的变异。
附：英文原文
Title: Imprinting sets the stage for speciation
Author: Yusan Yang, Maria R. Servedio, Corinne L. Richards-Zawacki
Issue&Volume: 2019-10-02
Abstract:
Sexual imprinting—a phenomenon in which offspring learn parental traits and later use them as a model for their own mate preferences—can generate reproductive barriers between species1. When the target of imprinting is a mating trait that differs among young lineages, imprinted preferences may contribute to behavioural isolation and facilitate speciation1,2. However, in most models of speciation by sexual selection, divergent natural selection is also required; the latter acts to generate and maintain variation in the sexually selected trait or traits, and in the mating preferences that act upon them3. Here we demonstrate that imprinting, in addition to mediating female mate preferences, can shape biases in male–male aggression. These biases can act similarly to natural selection to maintain variation in traits and mate preferences, which facilitates reproductive isolation driven entirely by sexual selection. Using a cross-fostering study, we show that both male and female strawberry poison frogs (Oophaga pumilio) imprint on coloration, which is a mating trait that has diverged recently and rapidly in this species4. Cross-fostered females prefer to court mates of the same colour as their foster mother, and cross-fostered males are more aggressive towards rivals that share the colour of their foster mother. We also use a simple population-genetics model to demonstrate that when both male aggression biases and female mate preferences are formed through parental imprinting, sexual selection alone can (1) stabilize a sympatric polymorphism and (2) strengthen the trait–preference association that leads to behavioural reproductive isolation. Our study provides evidence of imprinting in an amphibian and suggests that this rarely considered combination of rival and sexual imprinting can reduce gene flow between individuals that bear divergent mating traits, which sets the stage for speciation by sexual selection.
DOI: 10.1038/s41586-019-1599-z
Source: https://www.nature.com/articles/s41586-019-1599-z
Nature：《自然》，创刊于1869年。隶属于施普林格·自然出版集团，最新IF：69.504
官方网址：http://www.nature.com/
投稿链接：http://www.nature.com/authors/submit_manuscript.html
本期文章：《自然》：Online/在线发表
