Center for Conservation and Evolutionary Genetics, Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC 20008, USA.
Mol Ecol. 2011 Jan;20(2):409-19. doi: 10.1111/j.1365-294X.2010.04940.x. Epub 2010 Nov 18.
The ring-tailed coati (Nasua nasua) is the only coati species in which social groups contain an adult male year round, although most males live solitarily. We compared reproductive success of group living and solitary adult male coatis to determine the degree to which sociality affects reproductive success. Coati mating is highly seasonal and groups of female coatis come into oestrus during the same 1-2 week period. During the mating season, solitary adult males followed groups and fought with the group living male. This aggression was presumably to gain access to receptive females. We expected that high reproductive synchrony would make it difficult or impossible for the one group living male to monopolize and defend the group of oestrous females. However, we found that group living males sired between 67-91% of the offspring in their groups. This reproductive monopolization is much higher than other species of mammals with comparably short mating seasons. Clearly, living in a group greatly enhanced a male's reproductive success. At the same time, at least 50% of coati litters contained offspring sired by extra-group males (usually only one offspring per litter); thus, resident males could not prevent extra-group matings. The resident male's reproductive advantage may reflect female preference for a resident male strong enough to fend off competing males.
环尾猫鼬（Nasua nasua）是唯一一种全年都有成年雄性生活在群体中的浣熊科动物，尽管大多数雄性是独居的。我们比较了群居和独居成年雄性环尾猫鼬的繁殖成功率，以确定社会性对繁殖成功率的影响程度。环尾猫鼬的交配具有很强的季节性，雌性环尾猫鼬群体在同一 1-2 周的发情期进入发情期。在交配季节，独居的成年雄性会跟随群体，并与群居的雄性战斗。这种攻击可能是为了接近有生育能力的雌性。我们预计，高度的繁殖同步性会使一个群居的雄性难以或不可能垄断和保护发情的雌性群体。然而，我们发现，群居雄性在其群体中生育的后代比例在 67-91%之间。这种繁殖垄断的程度远高于其他具有类似短交配季节的哺乳动物物种。显然，生活在群体中极大地提高了雄性的繁殖成功率。与此同时，至少有 50%的环尾猫鼬幼崽是由群体外的雄性（通常每窝只有一个后代）生育的；因此，雄性无法阻止群体外的交配。雄性的繁殖优势可能反映了雌性对足够强壮、能够抵御竞争雄性的雄性的偏好。
