Irwin Darren E, Bensch Staffan, Irwin Jessica H, Price Trevor D
Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, BC, Canada V6T 1Z4.
Science. 2005 Jan 21;307(5708):414-6. doi: 10.1126/science.1105201.
Ring species, which consist of two reproductively isolated forms connected by a chain of intergrading populations, have often been described as examples of speciation despite gene flow between populations, but this has never been demonstrated. We used amplified fragment length polymorphism (AFLP) markers to study gene flow in greenish warblers (Phylloscopus trochiloides). These genetic markers show distinct differences between two reproductively isolated forms but gradual change through the ring connecting these forms. These findings provide the strongest evidence yet for "speciation by force of distance" in the face of ongoing gene flow.
环物种由两个生殖隔离的形态组成，它们通过一系列渐变种群相连，尽管种群间存在基因流动，但常被视为物种形成的例子，不过这一点从未得到证实。我们利用扩增片段长度多态性（AFLP）标记来研究淡绿柳莺（Phylloscopus trochiloides）的基因流动。这些遗传标记显示出两个生殖隔离形态之间存在明显差异，但在连接这两个形态的环中呈现出渐变。这些发现为在持续基因流动情况下的“距离隔离导致物种形成”提供了迄今为止最有力的证据。
