Interspecific dominance relationships and hybridization between black-capped and mountain chickadees
Interspecific dominance relationships and hybridization between black-capped and mountain chickadees
复制标题
DOI：
10.1093/beheco/arr229
复制
发表时间：
2012-05-01
影响因子：
2.4
通讯作者：
Otter, K. A.
中科院分区：
文献类型：
--
作者：
Grava, A.;Grava, T.;Otter, K. A.
黑顶山雀（Poecile atricapillus）和山地山雀（P. gambeli）由于栖息地偏好的差异而在生态上被隔离。然而，加拿大西北部的林业实践创造了针叶林（山雀栖息地）和落叶林斑块（黑顶栖息地）的马赛克，这可能解释了这两个密切相关的物种之间观察到的区域同域性的情况。在Poecile物种中，同种个体之间的社会等级影响生活史参数，如配偶选择。因此，种间的社会等级可能会驱使这两个密切相关的物种之间的杂交。通过野外观察和鸟舍试验，我们证明了黑顶山雀是山雀的优势种群。使用物种特异性表型（羽毛），线粒体DNA（mtDNA），以评估母体基因型和微卫星标记的组合，我们证实，遗传混合发生在我们的接触区，但亲子关系的模式出现方向。除了一个成年杂种外，所有的杂种都被鉴定为山雀，并具有山雀mtDNA。此外，所有的雏鸟微卫星检测到混合物种的祖先都从山山雀巢与双方参加父母山山雀表型。所有的mtDNA从这些雏鸟是山雀除了一个人，在所有的情况下，这些雏鸟表现出遗传模式已经出现通过extrapair交配之间的女性和男性黑顶山雀。我们的研究结果表明，杂交可能会导致男性的山雀具有较低的表达的首选性状（优势）比黑帽山雀。
Black-capped chickadees (Poecile atricapillus) and mountain chickadees (P. gambeli) are ecologically segregated due to differences in habitat preference. However, forestry practices in northwestern Canada have created a mosaic of coniferous (mountain chickadee habitat) and deciduous forest patches (black-capped habitat), which might explain cases of observed regional sympatry between these 2 closely related species. In Poecile species, social hierarchies amongst conspecific individuals influence life-history parameters such as mate choice. As a result, interspecific social hierarchies might drive hybridization between these 2 closely related species. By conducting field observations and aviary experiments, we demonstrated that black-capped chickadees are dominant over mountain chickadees. Using a combination of species-specific phenotypes (plumage), mitochondrial DNA (mtDNA) to assess maternal genotype, and microsatellite markers, we confirmed that genetic mixing occurs within our contact zone but that the pattern of parentage appears directional. All but one of the adult hybrids was phenotypically identified as mountain chickadee and had mountain chickadee mtDNA. Furthermore, all nestlings where microsatellites detected mixed-species ancestry were from mountain chickadee nests with both attending parents having mountain chickadee phenotypes. All mtDNA from these nestlings was mountain chickadee except for one individual, and in all cases, these nestlings showed genetic patterns of having arisen through extrapair copulations between female mountain and male black-capped chickadees. Our results suggest that hybridization may result from males of the mountain chickadees having lower expression of a preferred trait (dominance) than the black-capped chickadees.