Johansson Helena, Surget-Groba Yann, Thorpe Roger S
School of Biological Sciences, College of Natural Sciences, Bangor University, Deiniol Road, Bangor, Gwynedd, LL57 2UW, UK.
Mol Ecol. 2008 Oct;17(20):4425-32. doi: 10.1111/j.1365-294X.2008.03923.x. Epub 2008 Sep 18.
Dispersal is a key component of an organism's life history and differences in dispersal between sexes appear to be widespread in vertebrates. However, most predictions of sex-biased dispersal have been based on observations of social structure in birds and mammals and more data are needed on other taxa to test whether these predictions apply in other organisms. Caribbean anole lizards are important model organisms in various biological disciplines, including evolutionary biology. However, very little is known about their dispersal strategies despite the importance of dispersal for population structure and dynamics. Here we use nine microsatellite markers to assess signatures of sex-biased dispersal on two spatial sampling scales in Anolis roquet, an anole endemic to the island of Martinique. Significantly higher gene diversity (H(S)) and lower mean assignment value (mAIC) was found in males on the larger spatial sampling scale. Significant heterozygote deficit (F(IS)), lower population differentiation (F(ST)), mAIC and variance of assignment index (vAIC) was found in males on the smaller spatial scale. The observation of male biased dispersal conform with expectations based on the polygynous mating system of Anolis roquet, and contributes to an explanation of the contrasting patterns of genetic structure between maternal and biparental markers that have been reported previously in this, and other anoline, species.
扩散是生物体生活史的一个关键组成部分,脊椎动物中两性之间的扩散差异似乎很普遍。然而,大多数关于性别偏向扩散的预测都是基于对鸟类和哺乳动物社会结构的观察,还需要更多关于其他分类群的数据来检验这些预测是否适用于其他生物。加勒比安乐蜥是包括进化生物学在内的各种生物学学科中的重要模式生物。然而,尽管扩散对种群结构和动态很重要,但人们对它们的扩散策略知之甚少。在这里,我们使用九个微卫星标记,在两个空间采样尺度上评估马提尼克岛特有的安乐蜥罗凯安乐蜥性别偏向扩散的特征。在较大空间采样尺度上,雄性的基因多样性(H(S))显著更高,平均分配值(mAIC)更低。在较小空间尺度上,雄性出现了显著的杂合子缺失(F(IS))、较低的种群分化(F(ST))、mAIC和分配指数方差(vAIC)。观察到的雄性偏向扩散符合基于罗凯安乐蜥多配交配系统的预期,并有助于解释此前在该物种和其他安乐蜥物种中报道的母系标记和双亲标记之间遗传结构的对比模式。