Asexual hybrids are important model organisms for addressing questions in evolution and ecology, especially for understanding the role of hybridization in speciation. They are rare in nature and several hypotheses have been suggested to explain this. We use an asexual fish, the Amazon molly (Poecilia formosa), to establish the area in which it was formed via hybridization 125 000 years ago. Using species distribution models and climate models for the Last Interglacial (LIG) we found that model projections to the LIG show a similar map to the present climate model and parental species potentially overlapped in a relatively small area near Tampico, Mexico. This makes P. formosa one of a few hybrid species for which we know the parental species, the time of hybridization, and likely the place of hybridization. Based on the small area of overlap, our data is in agreement with the idea that asexual hybrids may be rare not because they are evolutionary dead ends but are formed rarely.

中文翻译：

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根据历史气候数据，放置无性亚马逊软体动物（Poecilia formosa）的杂交起源

无性杂种是解决进化和生态问题的重要模型生物，尤其是对于了解杂交在物种形成中的作用而言。它们本质上是罕见的，并且提出了一些假设来解释这一点。我们使用一种无​​性鱼，即亚马逊莫利（Poecilia formosa），来建立它在125 000年前通过杂交形成的区域。使用上一次冰间期（LIG）的物种分布模型和气候模型，我们发现对LIG的模型投影显示了与当前气候模型相似的地图，并且亲本物种可能在墨西哥坦皮科附近相对较小的区域重叠。这使得福寿螺我们知道其亲本物种，杂交时间以及杂交地点的几种杂种之一。基于重叠的小区域，我们的数据与以下观点一致：无性杂种可能很少见，并非因为它们是进化的死胡同，而很少形成。