Demographic Advantages of Eusociality

群居昆虫一直是生物学家的进化论难题。他们进化出了很少或永远不会繁殖的工人种姓。但是，阻止生殖的基因是如何在人群中变得常见的呢？答案是，工人帮助亲属繁衍后代，尽管他们不表达工人行为的基因，但他们确实拥有这些基因，并将它们传递给他们的后代。理论和经验证据的结合表明，给予的援助必须是相当可观的：工人通常必须增加亲属的繁衍，而不是减少自己的繁衍。如何实现这种规模的繁殖效率是拟议研究的主要主题，重点是没有进化种姓专门化的原始群居昆虫。数学模型将展示简单而可信的死亡率和生殖时机模式如何导致规模的这些效率。对黄蜂的实地研究将用来检验这些模型。这项工作的结果将是更好地理解为什么一些物种从事利他行为，为什么其他物种不这样做。这些洞察力可能导致人们认识到群居昆虫和高等动物利他主义进化的相似之处。

The social insects have always posed an evolutionary puzzle to biologists. They have evolved worker castes which rarely or never reproduce. But how can genes that prevent reproduction ever become common in populations? The answer is that workers aid the reproduction of relatives who, though they do not express the genes for worker behavior, do possess them and transmit them to their offspring. A combination of theory and empirical evidence suggests that the aid given must be considerable: workers must generally increase the reproduction of their relatives by more than the amount that they decrease their own reproduction. How such reproductive efficiencies of scale can be achieved is the main theme of the proposed research, focusing on primitively social insects that have not evolved caste specializations. Mathematical models will show how simple and plausible patterns of mortality and reproductive timing can lead to these efficiencies of scale. Field studies of wasps will serve to test the models. The result of this work will be a better understanding of why some species engage in altruistic behavior and why others do not. These insights may lead to the recognition of similarities underlying the evolution of altruism in the social insects and higher animals.