Am Nat. 2019 Apr;193(4):598-607. doi: 10.1086/702249. Epub 2019 Feb 15.
Codivergence of mating traits and mate preferences can lead to behavioral isolation among lineages in early stages of speciation. However, mate preferences limit gene flow only when expressed as mate choice, and numerous factors might be more important than preferences in nature. In the extremely color polytypic strawberry poison frog (Oophaga pumilio), female mate preferences have codiverged with color in most allopatric populations tested. Whether these lab-assayed preferences predict mating (gene flow) in the wild remains unclear. We observed courting pairs in a natural contact zone between red and blue lineages until oviposition or courtship termination. We found color-assortative mating in a disturbed habitat with high population density but not in a secondary forest with lower density. Our results suggest color-assortative O. pumilio mate choice in the wild but also mating patterns that do not match those predicted by lab-assayed preferences.
交配特征和配偶偏好的趋同进化可能导致物种形成早期谱系之间的行为隔离。然而,只有当配偶偏好表现为择偶时,才会限制基因流动,而且在自然界中,许多因素可能比偏好更为重要。在极度颜色多态的草莓毒蛙(Oophaga pumilio)中,大多数测试的异地种群中,雌性配偶偏好与颜色趋同进化。这些在实验室中检测到的偏好是否能预测野外的交配(基因流动)尚不清楚。我们在红色和蓝色谱系之间的自然接触带观察到求偶对,直到产卵或求偶结束。我们发现,在一个人口密度高的受干扰栖息地中存在颜色选择性交配,但在一个人口密度较低的次生林中则没有。我们的结果表明,草莓毒蛙在野外存在颜色选择性择偶,但也存在与实验室检测到的偏好不匹配的交配模式。