Abstract：
Group size is an important trait for many ecological and evolutionary processes. However, it is not a trait possessed by individuals but by social groups, and as many genomes contribute to group size understanding its genetic underpinnings and so predicting its evolution is a conceptual challenge. Here I suggest how group size can be modelled as a joint phenotype of multiple individuals, and so how models for evolution accounting for indirect genetic effects are essential for understanding the genetic variance of group size. This approach makes it clear that (a) group size should have a larger genetic variance than initially expected as indirect genetic effects always contribute exactly as much as direct genetic effects and (b) the response to selection of group size should be faster than expected based on direct genetic variance alone as the correlation between direct and indirect effects is always at the maximum positive limit of 1. Group size should therefore show relatively rapid evolved increases and decreases, the consequences of which and evidence for I discuss.
摘要：
群体规模是许多生态和进化过程的重要特征。然而,它不是个人拥有的特质，而是社会群体拥有的特质，许多基因组有助于群体大小理解其遗传基础，因此预测其进化是一个概念上的挑战。在这里，我建议如何将群体大小建模为多个个体的联合表型，因此，解释间接遗传效应的进化模型对于理解群体大小的遗传变异至关重要。这种方法清楚地表明，1）群体规模的遗传变异应该比最初预期的更大，因为间接遗传效应的贡献总是与直接遗传效应的贡献完全相同；2）对群体规模选择的响应应该比基于直接遗传变异的预期更快，因为直接和间接效应之间的相关性始终处于最大正极限1。因此，群体规模应该表现出相对快速的增长和减少，我讨论的后果和证据。
