Driscoll Don A
Department of Zoology, University of Western Australia, Nedlands, Perth, Western Australia, 6907, Australia.
Evolution. 1998 Aug;52(4):1147-1157. doi: 10.1111/j.1558-5646.1998.tb01841.x.
I describe the genetic structure of two frog species, Geocrinia rosea and Geocrinia lutea, using allozyme electrophoresis to understand population structure and thereby possible mechanisms of divergence and speciation. The sampling regimes represented the entire range of both species and provided replicated tests of the impact of ridges, rivers, and dry forest on gene flow. Geocrinia rosea and G. lutea were highly genetically subdivided (F = 0.69, 0.64, respectively). In the extreme, there were fixed allelic differences between populations that were only 4 km (G. rosea) or 1.25 km (G. lutea) apart. In addition to localized divergence, two-dimensional scaling of genetic distance allowed the recognition of broad-scale genetic groups, each consisting of several sample sites. Patterns of divergence were unrelated to the presence of ridges, rivers, or dry forest. I argue that range contraction and expansion, combined with extreme genetic divergence in single, isolated populations, best accounts for the genetic structure of these species.
我运用等位酶电泳来描述两种蛙类物种——玫瑰姬蛙（Geocrinia rosea）和黄斑姬蛙（Geocrinia lutea）的遗传结构，以了解种群结构以及可能的分化和物种形成机制。采样方案涵盖了这两个物种的整个分布范围，并对山脊、河流和干燥森林对基因流动的影响进行了重复测试。玫瑰姬蛙和黄斑姬蛙在遗传上高度细分（F值分别为0.69和0.64）。在极端情况下，相距仅4公里（玫瑰姬蛙）或1.25公里（黄斑姬蛙）的种群之间存在固定的等位基因差异。除了局部性分化外，遗传距离的二维标度还能识别出广泛的遗传群体，每个群体由几个采样点组成。分化模式与山脊、河流或干燥森林的存在无关。我认为，范围收缩和扩张，再加上单个孤立种群中的极端遗传分化，最能解释这些物种的遗传结构。
