Boorman S A
Proc Natl Acad Sci U S A. 1974 May;71(5):2103-7. doi: 10.1073/pnas.71.5.2103.
A population genetic model is presented for selection of a Mendelian trait controlling for cooperative behavior between unrelated conspecifics. Under simple and robust assumptions, such a trait will be selected on a frequency-dependent basis, with a critical threshold frequency (beta(2) (crit)) of the social trait which must be exceeded before favorable selection of this trait can occur. Existence of this threshold gives rise to a basic evolutionary problem as to how evolution from an asocial state (beta congruent with 0) to a social state (beta congruent with 1) can take place. A formal model of this evolution is proposed which rests on obstacles to random mixing (population viscosity). The key fact is the possibility that an initial local concentration of the social trait may be able to spread out under the joint effects of selection and migration and eventually take over a much larger species population. It is argued that this model is the first formal model to capture the ideas of Wright concerning group selection of an altruist trait in an island-structured population.
提出了一种群体遗传模型，用于选择控制无关同种个体间合作行为的孟德尔性状。在简单且稳健的假设下，这样的性状将在频率依赖的基础上被选择，社会性状存在一个关键阈值频率（β(2)（临界值）），在该性状能够被有利选择之前，必须超过这个阈值。这个阈值的存在引发了一个基本的进化问题，即从非社会状态（β近似于0）到社会状态（β近似于1）的进化如何发生。提出了这种进化的形式模型，该模型基于随机混合的障碍（群体粘性）。关键事实是，社会性状的初始局部集中有可能在选择和迁移的共同作用下扩散开来，并最终占据更大的物种群体。有人认为，这个模型是第一个正式模型，能够捕捉赖特关于岛屿结构群体中利他性状的群体选择的思想。
