Extrapair paternity and egg hatchability in tree swallows: evidence for the genetic compatibility hypothesis?
Extrapair paternity and egg hatchability in tree swallows: evidence for the genetic compatibility hypothesis?
复制标题
DOI：
10.1093/beheco/10.3.304
复制
发表时间：
1999-05-01
影响因子：
2.4
通讯作者：
Robertson, RJ
中科院分区：
文献类型：
--
作者：
Kempenaers, B;Congdon, B;Robertson, RJ
树燕（Tachycineta bicolor）是鸟类中配对外亲子关系最高水平的燕子之一，并且有证据表明雌性可以控制谁是其后代的父亲。然而，目前尚不清楚雌性燕子从与多个雄性交配中获得什么好处。使用微卫星DNA。通过指纹识别，我们研究了与筑巢成功以及雄性、雌性和后代特征之间的关系。超过 70% 的巢穴中含有额外配对的幼崽，超过一半的后代都是额外配对的。在巢穴中，额外的幼崽通常由几只雄性所生。尽管对所有常住雄性和一些流动雄性进行了筛查，但我们只能识别出所有外对后代中 21% 的亲生父亲。所有被识别的额外雄性都是近邻。外对雄性在任何测量的特征上与内对雄性没有区别，除了前者比后者具有更大的泄殖腔突起。外对雄性在获得亲子关系方面与没有生育额外幼崽的雄性同样成功。在混合亲子关系的巢中，配对外的幼崽在体型或质量上与配对内的幼崽没有差异。然而，有额外配对幼崽的巢穴比没有额外配对幼崽的巢穴孵化成功率更高。所有检查的未孵化蛋均已受精，因此孵化失败是由于胚胎死亡造成的。现有数据符合遗传多样性和遗传相容性假说，但不符合优良基因假说。
Tree swallows (Tachycineta bicolor) show one of the highest levels of extrapair paternity in birds, and there is evidence that females have control over who fathers their offspring. However, it is unclear which benefits female tl ee swallows obtain from mating with multiple males. Using microsatellite DNA. fingerprinting, we studied extrapair paternity in relation to nesting success and male, female, and offspring characteristics. More than 70% of all nests contained extrapair young, and more than half of all offspring were extrapair. Within broods, the extrapair young were often fathered by several males. Despite screening all resident and some floater males, we could identify the biological father of only 21% of all extrapair offspring. All identified extrapair males were close neighbors. Extrapair males did not differ from within-pair males in any of the measured characteristics, except that the former had larger cloacal protuberances than the latter Extrapair males were equally successful in gaining paternity in their own broods as males that did not father extra young. In nests with mixed paternity, extrapair young did not differ from within-pair young in body size or mass. However, nests with extrapair young had higher hatching success than nests without extrapair young. All examined unhatched eggs were fertilized and thus hatch failure resulted from embryo mortality. The available data are in accordance with the genetic diversity and the genetic compatibility hypothesis, but not with the good genes hypothesis.