Data from: Natural genetic variation in social environment choice: context-dependent gene-environment correlation in Drosophila melanogaster

Gene-environment correlation (rGE) occurs when an individual’s genotype determines its choice of environment, generating a correlation between environment and genotype frequency. In particular, social rGE, caused by genetic variation in social environment choice, can critically determine both individual development and the course of social selection. Despite its foundational role in social evolution and developmental psychology theory, natural genetic variation in social environment choice has scarcely been examined empirically. Drosophila melanogaster provides an ideal system for investigating social rGE. Flies live socially in nature and have many opportunities to make social decisions; and natural, heterozygous genotypes may be replicated, enabling comparisons between genotypes across environments. Using this approach, I show that all aspects of social environment choice vary among natural genotypes, demonstrating pervasive social rGE. Surprisingly, genetic variation in group-size preference was density-dependent, indicating that the behavioral and evolutionary consequences of rGE may depend on the context in which social decisions are made. These results provide the first detailed investigation of social rGE, and illustrate that that genetic variation may influence organismal performance by specifying the environment in which traits are expressed.基因-环境相关性（Gene-environment correlation, rGE）指当个体的基因型决定其环境选择时，所催生的环境与基因型频率之间的统计关联。具体而言，由社会环境选择的遗传变异所引发的社会型基因-环境相关性（social rGE），可从根本上调控个体发育进程与社会选择的演化历程。尽管社会型基因-环境相关性在社会演化与发展心理学理论中占据基础性地位，但针对社会环境选择的自然遗传变异，目前鲜有实证研究予以系统考察。黑腹果蝇（Drosophila melanogaster）是探究社会型基因-环境相关性的理想实验体系：该物种在自然环境中营群居生活，具备丰富的社会决策契机；且其天然杂合基因型可被重复复刻，得以实现不同环境下各基因型间的比对分析。借助该实验体系，本研究证实社会环境选择的所有维度均存在天然基因型间的差异，证明社会型基因-环境相关性广泛存在。令人意外的是，种群规模偏好的遗传变异具有密度依赖性，这表明基因-环境相关性的行为与演化后果，可能取决于社会决策发生的具体情境。本研究成果首次对社会型基因-环境相关性开展了详尽的系统性探究，并揭示出遗传变异可通过界定性状表达所处的环境，来影响生物体的表现型功能。