Latitudinal variation in sexual dimorphism in a freshwater fish group
Latitudinal variation in sexual dimorphism in a freshwater fish group
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淡水鱼群性别二态性的纬度变化
DOI：
10.1093/biolinnean/blaa166
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发表时间：
2020
影响因子：
1.9
通讯作者：
Fujimot
中科院分区：
文献类型：
--
作者：
Sumarto Bayu K A;Kobayashi Hirozumi;Kakioka Ryo;Tanaka Rieko;Maeda Ken;Tran Hau D;Koizumi Noriyuki;Morioka Shinsuke;Bounsong Vongvichith;Watanabe Katsutoshi;Musikasinthorn Prachya;Tun Sein;Yun L K C;Anoop V K;Raghavan Rajeev;Masengi Kawilarang W A;Fujimot
热带动物的特点是与温带动物相比，它们有华丽的装饰和明显的体色。最近的一些研究假设，性选择的压力在热带地区比在温带地区更强。虽然纬度和两性异形程度之间的负相关性支持这一假设，但在这种比较研究中应考虑到同源性。Adrianichthyidae是一个淡水鱼类家族，在东南亚和东亚地区分布广泛，通过比较其个体大小和鱼鳍长度的两性异形程度，发现低纬度鱼类的两性异形程度高于高纬度鱼类。系统发育广义最小二乘分析使用线粒体DNA同源性表明，纬度和性二态性的程度之间的负相关性变得不显着时，同源性被认为是，但解释的方差性二态性的程度不仅由同源性，但也几乎同样由纬度。祖先状态的重建表明，即使在主要的分支中，性二型也是独立进化的。这些发现与热带物种比温带物种面临更强的性选择压力的观点一致。我们讨论了性选择压力的纬度变化的可能原因。
Tropical animals are characterized by showy ornaments and conspicuous body colours as compared with their temperate relatives. Some recent studies have hypothesized that sexual selection pressures are stronger in the tropics than in the temperate zone. Although negative correlations between latitude and the degree of sexual dimorphism would support this hypothesis, phylogeny should be taken into account in such comparative studies. Comparisons of the degree of sexual dimorphism in body size and fin lengths among species of the Adrianichthyidae, a freshwater fish family having a wide geographical range throughout Southeast and East Asia, revealed that lower latitude species are sexually more dimorphic in all characters than higher latitude species. Phylogenetic generalized least squares analyses using a mitochondrial DNA phylogeny demonstrated that the negative correlations between latitude and the degree of sexual dimorphism become non-significant when phylogeny is considered, but that the variance in the degree of sexual dimorphism is explained not only by phylogeny but also almost equally by latitude. Ancestral state reconstruction indicated that sexual dimorphisms have evolved independently even within major clades. These findings are consistent with the view that tropical species are exposed to stronger sexual selection pressures than temperate species. We discuss possible causes of the latitudinal variation in sexual selection pressure.