Divergent Genital Morphologies and Female–Male Covariation in Watersnakes
Divergent Genital Morphologies and Female–Male Covariation in Watersnakes
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水蛇不同的生殖器形态和雌雄共变
DOI：
10.1093/icb/icac020
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发表时间：
2022
影响因子：
2.6
通讯作者：
Brennan, P. L. R.
中科院分区：
文献类型：
--
作者：
Greenwood, J. F.;Lara Granados, G.;Secor, S. M.;Todd, B. D.;Showalter, I.;Hedrick, B. P.;Brennan, P. L. R.
生殖器的进化可以由不同的选择压力驱动。在分类群中，我们看到雄性和雌性之间的共变的证据，以及密切相关的物种之间的不同的生殖器形态。对共同进化的雄性和雌性生殖器的形态变化的定量分析尚未在脊椎动物中显示。本研究使用二维和三维几何形态测量学方法定量比较了三种水蛇（姐妹分类群Nerodia fasciata，N.一个是亲戚，一个是亲戚。rhombifer），以解决生殖器形态和分歧时间之间的关系，在一个系统中，性冲突可能会驱动性对抗的生殖器性状的共同进化。我们对不同物种之间形状差异的成对比较表明，姐妹物种的雄性和雌性生殖器彼此之间存在显着差异，但彼此之间的相似性比N更大。菱形我们还确定，男性和女性的形状变化的主轴是相同的，与阴道袋和hemipenes更深的双叶相关的变化。在男性中，在半边莲基部的棘区域的突出与双叶的程度相权衡，这表明性冲突的改善，可能是由阴道袋入口的相对大小的变化驱动的，这可能使棘的有效性降低。
Genital evolution can be driven by diverse selective pressures. Across taxa we see evidence of covariation between males and females, as well as divergent genital morphologies between closely related species. Quantitative analyses of morphological changes in coevolving male and female genitalia have not yet been shown in vertebrates. This study uses 2D and 3D geometric morphometrics to quantitatively compare the complex shapes of vaginal pouches and hemipenes across three species of watersnakes (the sister taxaNerodia fasciata, N. sipedon, and a close relativeN. rhombifer) to address the relationship between genital morphology and divergence time in a system where sexual conflict may have driven sexually antagonistic coevolution of genital traits. Our pairwise comparisons of shape differences across species show that the sister species have male and female genitalia that are significantly different from each other, but more similar to each other than toN. rhombifer. We also determine that the main axes of shape variation are the same for males and females, with changes that relate to deeper bilobation of the vaginal pouch and hemipenes. In males, the protrusion of the region of spines at the base of the hemipene trades off with the degree of bilobation, suggesting amelioration of sexual conflict, perhaps driven by changes in the relative size of the entrance of the vaginal pouch that could have made spines less effective.