Percy FitzPatrick Institute, DST/NRF Centre of Excellence, University of Cape Town Rondebosch, 7701, South Africa ; Museum of Vertebrate Zoology, Department of Integrative Biology, University of California 3101 Valley Life Science Building, Berkeley, California, 94720, USA.
Ecol Evol. 2012 Nov;2(11):2710-21. doi: 10.1002/ece3.390. Epub 2012 Sep 27.
The range of a species is the result of the relative contribution of spatial tracking of environmental requirements and adaptation to ecological conditions outside the ancestral niche. The appearance of novel habitats caused by climatic oscillation can promote range expansion and accompanying demographic growth. The demographic dynamics of populations leave a signal in \ patterns. We modeled three competing scenarios pertaining to the circumstance of a range expansion by the Karoo Scrub-Robin into newly available habitat resulting from the increasing aridification of southern Africa. Genetic variation was contrasted with the theoretical expectations of a spatial range expansion, and compared with data of a putative adaptive trait. We infer that this bird likely colonized the arid zone, as a consequence of adaptive evolution in a small peripheral population, followed by an expansion with recurrent exchange of migrants with the ancestral populations.
物种的分布范围是环境需求的空间追踪和对祖先生态位以外生态条件适应的相对贡献的结果。气候波动导致的新栖息地的出现可以促进分布范围的扩大和伴随而来的种群增长。种群的人口动态在格局中留下了信号。我们为 Karoo Scrub-Robin 进入由于南非日益干旱而产生的新栖息地的分布范围扩张情况，建立了三个相互竞争的情景模型。我们将遗传变异与空间分布范围扩张的理论预期进行了对比，并与假定的适应性状的数据进行了比较。我们推断，这种鸟类可能是由于小的边缘种群的适应性进化而殖民到干旱区，然后随着与祖先种群的移民的反复交换而扩张。
