Department of Health Care Policy, Harvard Medical School, Boston, MA 02115, USA.
Sci Rep. 2012;2:845. doi: 10.1038/srep00845. Epub 2012 Nov 13.
Biologists have devoted much attention to assortative mating or homogamy, the tendency for sexual species to mate with similar others. In contrast, there has been little theoretical work on the broader phenomenon of homophily, the tendency for individuals to interact with similar others. Yet this behaviour is also widely observed in nature. Here, we model how natural selection can give rise to homophily when individuals engage in social interaction in a population with multiple observable phenotypes. Payoffs to interactions depend on whether or not individuals have the same or different phenotypes, and each individual has a preference that determines how likely they are to interact with others of their own phenotype (homophily) or of opposite phenotypes (heterophily). The results show that homophily tends to evolve under a wide variety of conditions, helping to explain its ubiquity in nature.
生物学家一直关注的是交配的选择性或同型交配，即有性物种倾向于与相似的其他物种交配。相比之下，对于更广泛的同质性现象，即个体与相似的其他个体相互作用的趋势，理论研究却很少。然而，这种行为在自然界中也很常见。在这里，我们构建了一个模型，用于研究当个体在具有多种可观察表型的群体中进行社交互动时，自然选择如何导致同质性。互动的回报取决于个体是否具有相同或不同的表型，并且每个个体都有一种偏好，决定了他们与自己的表型（同质性）或相反的表型（异质性）的其他个体进行互动的可能性。结果表明，同质性往往在各种条件下进化，有助于解释其在自然界中的普遍性。
