Male greater sac-winged bats gain direct fitness benefits when roosting in multimale colonies
Male greater sac-winged bats gain direct fitness benefits when roosting in multimale colonies
复制标题
DOI：
10.1093/beheco/ars003
复制
发表时间：
2012-05
影响因子：
2.4
通讯作者：
M. Nagy;M. Knörnschild;C. Voigt;F. Mayer
中科院分区：
文献类型：
--
作者：
M. Nagy;M. Knörnschild;C. Voigt;F. Mayer
以男性亲属为特征的社会群体在哺乳动物中很少见。理论预测，在这样的群体中繁殖的雄性需要克服当地配偶竞争的成本，这在一夫多妻制或混血交配系统中被认为是严重的。在这里，我们在一只有雄性亲缘关系的一夫多妻制哺乳动物中研究了雄性群体的规模是否会给雄性带来直接的健康益处，这可能会超过与相关雄性竞争领地和配偶的成本。我们利用长期的行为观察和大袋蝠的遗传数据，研究了生活在不同数量雄性居民群体中的雄性后宫蝙蝠一生繁殖成功的影响因素。我们发现，后宫男性的任期随着男性同居人数的增加而增加，并且后宫男性的任期解释了他们LBS的很大比例的变化。因此，我们的结果提供了证据，证明雄性从群体中的社会组织中获得直接的健康益处，其中包括额外的后宫领地和非后宫雄性。当非后宫雄性(通常与后宫雄性有血缘关系的年轻雄性)长期存在于群体中时，雄性迁入群体的数量显著减少，这表明较大的雄性群体可能能够更好地维持群体中的父系，从而也确保了未来的间接健康益处。
Social groups that are characterized by the presence of male kin are rare in mammals. Theory predicts that males reproducing in such groups need to overcome the costs of local mate competition, which are supposedly severe in polygynous or promiscuous mating systems. Here, we studied in a polygynous mammal with male philopatry whether male group size renders direct fitness benefits for males that could outweigh the costs of competing with related males for access to territories and mates. We used long-term behavioral observations and genetic data of the greater sac-winged bat to investigate the factors affecting lifetime breeding success (LBS) of harem males living in colonies that contain varying numbers of male residents. We show that tenure of harem males increased with the number of male coresidents and that harem male tenure explained a large proportion of variation in their LBS. Thus, our results provide evidence that males gain direct fitness benefits from a social organization in colonies that include additional harem territories and nonharem males. Immigration of males into colonies was significantly lower when nonharem males (young males that are often related to harem males) were permanently present in colonies, suggesting that larger male groups may be better able to maintain a patriline in a colony and thus also ensure future indirect fitness benefits.