Department of Ecology and Evolutionary Biology, 621 Charles E. Young Drive South, University of California, Los Angeles, CA 90095-1606, USA.
Ecol Lett. 2013 May;16(5):670-8. doi: 10.1111/ele.12100. Epub 2013 Mar 12.
Sympatric divergence in traits affecting species recognition can result from selection against cross-species mating (reproductive character displacement, RCD) or interspecific aggression (agonistic character displacement, ACD). When the same traits are used for species recognition in both contexts, empirically disentangling the relative contributions of RCD and ACD to observed character shifts may be impossible. Here, we develop a theoretical framework for partitioning the effects of these processes. We show that when both mate and competitor recognition depend on the same trait, RCD sets the pace of character shifts. Moreover, RCD can cause divergence in competitor recognition, but ACD cannot cause divergence in mate recognition. This asymmetry arises because males with divergent recognition traits may avoid needless interspecific conflicts, but suffer reduced attractiveness to conspecific females. Therefore, the key empirical issue is whether the same or different traits are used for mate recognition and competitor recognition.
同域物种分化会导致影响物种识别的特征发生分歧，这可能是由于对跨物种交配（生殖特征替代，RCD）或种间攻击（竞争特征替代，ACD）的选择造成的。当同一特征在两种情况下都用于物种识别时，从经验上区分 RCD 和 ACD 对观察到的特征变化的相对贡献可能是不可能的。在这里，我们开发了一个理论框架来划分这些过程的影响。我们表明，当配偶和竞争者识别都依赖于同一特征时，RCD 会设定特征变化的速度。此外，RCD 可以导致竞争者识别的分歧，但 ACD 不能导致配偶识别的分歧。这种不对称性是因为具有不同识别特征的雄性可能会避免不必要的种间冲突，但对同种雌性的吸引力降低。因此，关键的经验问题是用于配偶识别和竞争者识别的特征是否相同或不同。
