加拿大不列颠哥伦比亚大学和奥地利国际应用系统分析研究所的研究人员提出的新理论模型认为，选择性交配本身能促进那些拥有相同生态环境适应性以及可杂交物种的长期共存。这类物种包括蛙类、蟋蟀类、蚱蜢类和鱼类等。相关研究论文4月1日在线发表于《Nature》。
论文的主要作者、加州大学伯克利分校博士后研究员莱森说，现有的生物多样性理论只注重生物对环境的适应性，或者说适者生存这一点，但这无法解释人们所观察到的很多生物多样性现象。
他说，这项研究显示，不同物种能够在同一个栖息地中共存，但要满足两个前提条件：第一，它们使用的资源分配体系存在差异，只有这样，那些有不同配偶偏好的雌性动物才能占据不同的资源丰沛区域；第二，雌性动物必须为自己在选择配偶时的挑剔付出代价。
报告进一步解释说，雌性动物挑剔配偶所付出的代价对巩固物种间的界限具有重要作用，这也有效推动生物多样性的发展，因为对配偶有偏好的雌性动物不会随便进入那些它们不喜欢的雄性动物的领地。（生物谷 bioon.com）
doi:10.1038/nature10971
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Sexual selection enables long-term coexistence despite ecological equivalence
eithen K. M’Gonigle，Rupert Mazzucco, Sarah P. Otto1，Ulf Dieckmann
Empirical data indicate that sexual preferences are critical for maintaining species boundaries1, yet theoretical work has suggested that, on their own, they can have only a minimal role in maintaining biodiversity. This is because long-term coexistence within overlapping ranges is thought to be unlikely in the absence of ecological differentiation9. Here we challenge this widely held view by generalizing a standard model of sexual selection to include two ubiquitous features of populations with sexual selection: spatial variation in local carrying capacity, and mate-search costs in females. We show that, when these two features are combined, sexual preferences can single-handedly maintain coexistence, even when spatial variation in local carrying capacity is so slight that it might go unnoticed empirically. This theoretical study demonstrates that sexual selection alone can promote the long-term coexistence of ecologically equivalent species with overlapping ranges, and it thus provides a novel explanation for the maintenance of species diversity.
