Gill Frank B
The Academy of Natural Sciences, 1900 Benjamin Franklin Parkway, Philadelphia, Pennsylvania, 19103-1195.
Evolution. 1997 Apr;51(2):519-525. doi: 10.1111/j.1558-5646.1997.tb02439.x.
I compared the mtDNA compositions of two adjacent populations of Vermivora chrysoptera (golden-winged warbler) at different stages of transient hybridization with its sister species V. pinus (blue-winged warbler). Pinus mtDNA introgresses asymmetrically and perhaps rapidly into chrysoptera phenotypes without comparable reverse introgression of chrysoptera mtDNA into replacing pinus populations. Pinus mtDNA was virtually fixed (98%) in an actively hybridizing lowland population with varied phenotypes. Pinus mtDNA increased from 27% (n = 11) in 1988 to 70% (n = 10) in 1992 in successive samples of a highland population in the initial stages of hybridization. This population comprised mostly pure and slightly introgressed chrysoptera phenotypes. The rapid pace of asymmetrical introgression may be the result of initial invasion of chrysoptera populations by pioneering female pinus and/or an unknown competitive advantage of pinus females and their daughters over chrysoptera females.
我比较了金翅莺（Vermivora chrysoptera）与其姐妹物种蓝翅莺（V. pinus）处于不同阶段的瞬时杂交的两个相邻种群的线粒体DNA（mtDNA）组成。蓝翅莺的mtDNA不对称地、或许迅速地渗入金翅莺的表型中，而金翅莺的mtDNA没有相应地反向渗入取代蓝翅莺的种群。在一个具有不同表型的活跃杂交的低地种群中，蓝翅莺的mtDNA几乎是固定的（98%）。在杂交初始阶段的一个高地种群的连续样本中，蓝翅莺的mtDNA从1988年的27%（n = 11）增加到1992年的70%（n = 10）。这个种群主要由纯合的和轻度渗入的金翅莺表型组成。不对称渗入的快速步伐可能是由于先驱雌性蓝翅莺对金翅莺种群的初始入侵和/或蓝翅莺雌性及其后代相对于金翅莺雌性具有未知的竞争优势。
