Social and spatial effects on genetic variation between foraging flocks in a wild bird population
Social and spatial effects on genetic variation between foraging flocks in a wild bird population
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社会和空间对野鸟种群中觅食群体遗传变异的影响
作者：
Reinder Radersma;C. Garroway;A. W. Santure;I. de Cauwer;D. Farine;J. Slate;B. Sheldon
社交互动很少是随机的。在某些情况下，动物表现出同质性或异质性，即分别与相似或不相似的同种物质相互作用的倾向。遗传的同质性和异质性影响着种群的进化动态，因为它们潜在地影响着性选择和社会选择。在这里，我们调查了连续三年在大山雀群中觅食的社会互动和等位基因频率之间的联系。我们构建了共生网络，显式地描述了85,602群在60个采食点的分裂和合并(分裂-融合动力学)。在这些鸡群中的1711只鸟中，我们对962只个体进行了4701个常染色体单核苷酸多态(SNPs)的基因分型。通过将全基因组基因分型与对相同个体的重复实地观察相结合，我们能够在比以前可能的更精细的范围内调查社会结构和等位基因频率之间的联系。我们在种群水平上显式地解释了潜在的遗传结构的空间效应。我们用特征向量地图模拟了大山雀裂变-融合动态的社会结构和空间构型。方差划分显示，等位基因频率受到群体保真度的强烈影响(可解释27%-45%的方差)，因为个体倾向于与相同的同种特性保持联系。这些同种基因在遗传上的差异比预期的要大得多，表现为全基因组范围内对纯社会(即空间无关)群体偏好的异质性。全基因组同源性与空间构型相关联，表明了基因型的空间分离。我们没有发现推定的社会相关候选基因或任何其他SNP标记具有同质性或异质性的证据。总而言之，这些结果表明了区分社会和空间过程在确定人口结构方面的重要性。
Social interactions are rarely random. In some instances, animals exhibit homophily or heterophily, the tendency to interact with similar or dissimilar conspecifics, respectively. Genetic homophily and heterophily influence the evolutionary dynamics of populations, because they potentially affect sexual and social selection. Here, we investigate the link between social interactions and allele frequencies in foraging flocks of great tits (Parus major) over three consecutive years. We constructed co‐occurrence networks which explicitly described the splitting and merging of 85,602 flocks through time (fission–fusion dynamics), at 60 feeding sites. Of the 1,711 birds in those flocks, we genotyped 962 individuals at 4,701 autosomal single nucleotide polymorphisms (SNPs). By combining genomewide genotyping with repeated field observations of the same individuals, we were able to investigate links between social structure and allele frequencies at a much finer scale than was previously possible. We explicitly accounted for potential spatial effects underlying genetic structure at the population level. We modelled social structure and spatial configuration of great tit fission–fusion dynamics with eigenvector maps. Variance partitioning revealed that allele frequencies were strongly affected by group fidelity (explaining 27%–45% of variance) as individuals tended to maintain associations with the same conspecifics. These conspecifics were genetically more dissimilar than expected, shown by genomewide heterophily for pure social (i.e., space‐independent) grouping preferences. Genomewide homophily was linked to spatial configuration, indicating spatial segregation of genotypes. We did not find evidence for homophily or heterophily for putative socially relevant candidate genes or any other SNP markers. Together, these results demonstrate the importance of distinguishing social and spatial processes in determining population structure.