Moyle Robert G, Manthey Joseph D, Hosner Peter A, Rahman Mustafa, Lakim Maklarin, Sheldon Frederick H
Department of Ecology and Evolutionary Biology and Biodiversity Institute, The University of Kansas, Lawrence, KS, USA.
Department of Biology, University of Florida, Gainesville, FL, USA.
PeerJ. 2017 May 18;5:e3335. doi: 10.7717/peerj.3335. eCollection 2017.
Topographically complex regions often contain the close juxtaposition of closely related species along elevational gradients. The evolutionary causes of these elevational replacements, and thus the origin and maintenance of a large portion of species diversity along elevational gradients, are usually unclear because ecological differentiation along a gradient or secondary contact following allopatric diversification can produce the same pattern. We used reduced representation genomic sequencing to assess genetic relationships and gene flow between three parapatric pairs of closely related songbird taxa ( spiderhunters, leafbirds, and forktails) along an elevational gradient in Borneo. Each taxon pair presents a different elevational range distribution across the island, yet results were uniform: little or no gene flow was detected in any pairwise comparisons. These results are congruent with an allopatric "species-pump" model for generation of species diversity and elevational parapatry of congeners on Borneo, rather than in situ generation of species by "ecological speciation" along an elevational gradient.
地形复杂的区域通常包含密切相关的物种沿海拔梯度紧密并置的情况。这些海拔替代现象的进化原因，以及因此沿海拔梯度的大部分物种多样性的起源和维持，通常并不清楚，因为沿梯度的生态分化或异域分化后的二次接触都能产生相同的模式。我们使用简化基因组测序来评估婆罗洲沿海拔梯度的三对近缘鸣禽分类群（食蛛鸟、叶鹎和燕尾）之间的遗传关系和基因流。每对分类群在岛上呈现出不同的海拔范围分布，但结果是一致的：在任何成对比较中都几乎没有检测到基因流。这些结果与婆罗洲上同属物种多样性和海拔邻域分布的异域“物种泵”模型一致，而不是沿海拔梯度通过“生态物种形成”原地产生物种。
