Davis Jeremy S, Castillo Dean M, Moyle Leonie C
Department of Biology Indiana University Bloomington IN USA.
Ecol Evol. 2016 Dec 20;7(2):507-515. doi: 10.1002/ece3.2628. eCollection 2017 Jan.
Reinforcement occurs when hybridization between closely related lineages produces low-fitness offspring, prompting selection for elevated reproductive isolation specifically in areas of sympatry. Both premating and postmating prezygotic behaviors have been shown to be the target of reinforcing selection, but it remains unclear whether remating behaviors experience reinforcement, although they can also influence offspring identity and limit formation of hybrids. Here, we evaluated evidence for reinforcing selection on remating behaviors in , by comparing remating traits in females from populations historically allopatric and sympatric with . We found that the propensity to remate was not higher in sympatric females, compared to allopatric females, regardless of whether the first mated male was heterospecific or conspecific. Moreover, remating behavior did not contribute to interspecific reproductive isolation among any population; that is, females showed no higher propensity to remate following a heterospecific first mating than following a conspecific first mating. Instead, we found that females are less likely to remate after initial matings with unfamiliar males, regardless of species identity. This is consistent with one scenario of postmating sexual conflict in which females are poorly defended against postcopulatory manipulation by males with whom they have not coevolved. Our results are generally inconsistent with reinforcement on remating traits and suggest that this behavior might be more strongly shaped by the consequences of local antagonistic male-female interactions than interactions with heterospecifics.
当亲缘关系密切的谱系之间杂交产生适应性较差的后代时,就会出现强化现象,这促使在同域分布区域中,对提高生殖隔离进行选择。交配前和交配后合子前行为均已被证明是强化选择的目标,但尚不清楚再次交配行为是否会经历强化,尽管它也会影响后代的身份并限制杂种的形成。在这里,我们通过比较历史上异域分布和同域分布种群中雌性的再次交配特征,评估了对再次交配行为进行强化选择的证据。我们发现,与异域分布的雌性相比,同域分布的雌性再次交配的倾向并不更高,无论第一次交配的雄性是异种还是同种。此外,再次交配行为对任何种群间的种间生殖隔离都没有贡献;也就是说,雌性在异种第一次交配后再次交配的倾向并不比同种第一次交配后更高。相反,我们发现雌性在与陌生雄性初次交配后再次交配的可能性较小,无论物种身份如何。这与交配后性冲突中的一种情况一致,即雌性在面对与其没有共同进化的雄性的交配后操纵时,防御能力较差。我们的结果总体上与再次交配特征的强化不一致,表明这种行为可能更多地受到本地雌雄对抗性相互作用的后果影响,而非与异种的相互作用影响。