Lynch Alejandro, Baker Allan J
Department of Zoology, University of Toronto, Toronto, Ontario, M5S 1A1, Canada.
Department of Ornithology, Royal Ontario Museum, Toronto, Ontario, M5S 2C6, Canada.
Evolution. 1994 Apr;48(2):351-359. doi: 10.1111/j.1558-5646.1994.tb01316.x.
We investigated cultural evolution in populations of common chaffinches (Fringilla coelebs) in the Atlantic islands (Azores, Madeira, and Canaries) and neighboring continental regions (Morocco and Iberia) by employing a population-memetic approach. To quantify differentiation, we used the concept of a song meme, defined as a single syllable or a series of linked syllables capable of being transmitted. The levels of cultural differentiation are higher among the Canaries populations than among the Azorean ones, even though the islands are on average closer to each other geographically. This is likely the result of reduced levels of migration, lower population sizes, and bottlenecks (possibly during the colonization of these populations) in the Canaries; all these factors produce a smaller effective population size and therefore accentuate the effects of differentiation by random drift. Significant levels of among-population differentiation in the Azores, in spite of substantial levels of migration, attest to the differentiating effects of high mutation rates of memes, which allow the accumulation of new mutants in different populations before migration can disperse them throughout the entire region.
我们采用群体文化基因方法，对大西洋岛屿（亚速尔群岛、马德拉群岛和加那利群岛）及邻近大陆地区（摩洛哥和伊比利亚）的普通朱雀（Fringilla coelebs）种群的文化进化进行了研究。为了量化差异，我们使用了歌曲文化基因的概念，其定义为一个单音节或一系列能够传播的相连音节。尽管这些岛屿在地理上平均距离更近，但加那利群岛种群间的文化差异水平高于亚速尔群岛种群。这可能是由于加那利群岛的迁移水平降低、种群规模较小以及瓶颈效应（可能发生在这些种群的殖民化过程中）；所有这些因素导致有效种群规模较小，因此加剧了随机漂变的分化效应。尽管有大量的迁移，但亚速尔群岛种群间仍存在显著的差异水平，这证明了文化基因高突变率的分化作用，即允许新突变体在不同种群中积累，然后才会被迁移扩散到整个区域。
