Behaviour and Social Evolution of Wasps : Oxford University Press : 9780198540465 : 0198540469 : 04 Feb 1993 : In this book, Itô presents data on tropical wasps which suggest that kin-selection has been overemphasized as an evolutionary explanation of sociality. He concentrates on the Vespidae (paper wasps and hornets), a group much discussed by evolutionary biologists because it exhibits all stages of social evolution: subsociality, primitive eusociality, and advanced eusociality. The author reports field observations by himself and others in Central America, Asia, and Australia, showing that multiple egg-layers in a nest are not uncommon. Because coexistence of many 'queens' leads to lower relatedness among colony members than in single-queen colonies, he suggests that kin-selection may not be the most powerful force determining observed social patterns. Instead, subsocial wasps may first have aggregated for defense purposes in habitats with a high risk of predation, with mutualistic