芦鹀种群中的文化、遗传和形态进化的同时比较

我们比较了芦 (Emberizaschoeniclus)两个亚种组 ,即北部的薄喙亚种组和南部的厚喙亚种组的 10个种群中的文化、遗传和形态变异。使用了四个不同的变异标记物 ,其中两个用来测量文化分化 ,一个用来测量遗传分化 ,即微卫星等位基因的频次 ,一个用来测量种群的形态分化 ,即喙的高度。将遗传分化作为进化时间的尺度 ,我们计算了亚种组间和组内分化指标与所估计的进化率之间的相关性 ,发现只有文化定量指标和遗传分化与种群的形态分化相关 ,而两个文化分化指标之间没有关系 ,文化分化与遗传分化之间也没有关系。使用文化 -定量分化指标 ,发现亚种组间的文化进化率高于亚种内的文化进化率 ,提示鸣唱在防止杂交方面只有微弱的、也许是次要的作用。鸣唱定量特征的变异与微卫星频次相同 ,实际上在自然界中更可能是遗传决定的 ,这可以解释由于分析两个文化变异指标所得出的结果的不一致性。鸣唱的声学特性可能由于栖息地的差异或形态上的限制而发生了演变 ,而文化传播单位 (Meme)的特性可能由于学习鸣唱和文化传播而受到了影响

Simultaneous comparison of cultural, genetic and morphological evolution among reed bunting Emberiza schoeniclus populations

We compared cultural, genetic and morphological variation in a set of 10 reed bunting Emberiza schoeniclus populations of two subspecies groups, the northern thin billed and southern thick billed. We used four different markers of variation: two cultural divergence measures, quantitative characters and memetic frequencies; one measure of genetic divergence, i.e. microsatellite allele frequencies; and one measure of morphological divergence of populations, i.e. bill height. We calculated correlations among the divergence measures and estimated cultural evolutionary rates between and within subspecies groups using genetic divergence as the evolutionary time scale. We found that only cultural-quantitative and genetic divergence are correlated to morphological divergence of populations. There was no association between the two cultural divergence measures and between cultural and genetic divergence. Cultural evolutionary rates were higher between subspecies groups than within subspecies groups using cultural-quantitative divergence measures, suggesting only a weak and probably secondary function of song as a barrier to hybridisation. Variation in quantitative characters of song behaves similarly to microsatellite frequencies, and could be actually more genetic in nature. This could explain the incongruent results given by the analysis of the two "cultural" variation measures, which may refer to different aspects of song evolution. Acoustic properties of song may have evolved in response to habitat differences or to morphological constraints,while memetic properties may have been more affected by song learning and cultural transmission Acta Zoologica Sinica 50 (5): 730-737, 2004].