Cavedon Maria, vonHoldt Bridgett, Hebblewhite Mark, Hegel Troy, Heppenheimer Elizabeth, Hervieux Dave, Mariani Stefano, Schwantje Helen, Steenweg Robin, Watters Megan, Musiani Marco
Faculty of Environmental Design, University of Calgary, Calgary, AB, T2N 1N4, Canada.
Department of Ecology & Evolutionary Biology, Princeton University, 106A Guyot Hall, Princeton, NJ, 08544-2016, USA.
Conserv Biol. 2022 Feb 10. doi: 10.1111/cobi.13900.
Genetic mechanisms determining habitat selection and specialization of individuals within species have been hypothesized, but not tested at the appropriate individual level in nature. In this work, we analyzed habitat selection for 139 GPS-collared caribou belonging to three declining ecotypes sampled throughout Northwestern Canada. We used Resource Selection Functions (RSFs) comparing resources at used and available locations. We found that the three caribou ecotypes differed in their use of habitat suggesting specialization. On expected grounds, we also found differences in habitat selection between summer and winter, but also, originally, among the individuals within an ecotype. We next obtained Single Nucleotide Polymorphisms (SNPs) for the same caribou individuals, we detected those associated to habitat selection, and then identified genes linked to these SNPs. These genes had functions related in other organisms to habitat and dietary specializations, and climatic adaptations. We therefore suggest that individual variation in habitat selection was based on genotypic variation in the SNPs of individual caribou, indicating that genetic forces underlie habitat and diet selection in the species. We also suggest that the associations between habitat and genes that we detected may lead to lack of resilience in the species, thus contributing to caribou endangerment. Our work emphasizes that similar mechanisms may exist for other specialized, endangered species. This article is protected by copyright. All rights reserved.
关于决定物种内个体栖息地选择和特化的遗传机制已有假设，但尚未在自然环境中的适当个体水平上进行测试。在这项研究中，我们分析了加拿大西北部139只佩戴GPS项圈的驯鹿的栖息地选择情况，这些驯鹿分属于三种数量正在减少的生态型。我们使用资源选择函数（RSF）比较了被使用地点和可用地点的资源。我们发现，这三种驯鹿生态型在栖息地利用上存在差异，表明存在特化现象。不出所料，我们还发现夏季和冬季之间在栖息地选择上存在差异，而且最初在同一生态型的个体之间也存在差异。接下来，我们获取了同一批驯鹿个体的单核苷酸多态性（SNP），检测了与栖息地选择相关的SNP，然后鉴定了与这些SNP相关的基因。这些基因在其他生物中具有与栖息地、饮食特化以及气候适应相关的功能。因此，我们认为栖息地选择的个体差异是基于驯鹿个体SNP中的基因型变异，这表明遗传因素是该物种栖息地和饮食选择的基础。我们还认为，我们检测到的栖息地与基因之间的关联可能导致该物种缺乏恢复力，从而加剧了驯鹿的濒危状况。我们的研究强调，其他特化的濒危物种可能也存在类似机制。本文受版权保护。保留所有权利。
