Hasegawa Masaru, Arai Emi
Department of Evolutionary Studies of Biosystems Sokendai (The Graduate University for Advanced Studies) Miura-gun Kanagawa Japan.
Ecol Evol. 2017 Dec 12;8(2):992-996. doi: 10.1002/ece3.3723. eCollection 2018 Jan.
The effect of sexual selection on extinction risk remains unclear. In theory, sexual selection can lead to both increase and decrease extinction probability depending on the ecology of the study system. Thus, combining different groups might obscure patterns that can be found in groups that share similar ecological features. Using phylogenetic comparative analysis, we studied sexual plumage dimorphism in relation to the perceived risk of extinction in hirundines (subfamily: Hirundininae), in which all species are socially monogamous aerial foragers. Among the 72 species studied, five species are facing a perceived threat of extinction. Species with sexually dimorphic plumage had a higher risk of extinction than did species with sexually monomorphic plumage. Likewise, when focusing solely on tail ornamentation, species that exhibit a sexual dimorphism in tail length had a higher risk of extinction than did other species. In Hirundininae, which are affected a great deal by severe weather, sexual selection and the resultant sexual dimorphism would increase extinction risk.
性选择对灭绝风险的影响仍不明确。理论上，根据研究系统的生态环境，性选择既可能导致灭绝概率增加，也可能导致其降低。因此，将不同类群组合在一起可能会掩盖在具有相似生态特征的类群中所能发现的模式。通过系统发育比较分析，我们研究了燕科（亚科：燕亚科）中与感知到的灭绝风险相关的两性羽毛二态性，其中所有物种都是社会性一夫一妻制的空中觅食者。在所研究的72个物种中，有5个物种面临着感知到的灭绝威胁。具有两性异形羽毛的物种比具有两性同形羽毛的物种面临更高的灭绝风险。同样，当仅关注尾部装饰时，在尾长上表现出两性二态性的物种比其他物种面临更高的灭绝风险。在受恶劣天气影响很大的燕亚科中，性选择以及由此产生的两性二态性会增加灭绝风险。
