Sociobiology: The New Synthesis

Overview
"Sociobiology: The New Synthesis" (1975) by E. O. Wilson presents a sweeping attempt to account for social behavior across the animal kingdom through the lens of evolution. The book synthesizes findings from ethology, ecology, genetics, and population biology to argue that social structures and behavioral strategies can be understood as adaptations shaped by natural selection. Wilson writes with both the breadth of a naturalist and the ambition of a theorist, moving from ants and bees to birds, mammals, and ultimately humans.

Core argument
Wilson frames social behavior as an outcome of evolutionary pressures acting on individual survival and reproductive success. Central to the argument is the idea that behaviors that enhance inclusive fitness, benefiting kin as well as oneself, can be favored by selection. He emphasizes the adaptive value of cooperative and altruistic behaviors when those actions increase the propagation of shared genes. While focused on genetic explanations, Wilson also addresses how competition, conflict, mating systems, and ecological context shape social organization.

Methods and evidence
The book combines observational natural history, comparative analysis, and theoretical models. Wilson draws extensively on detailed studies of insects, especially ants and other eusocial species, where colony structure and task specialization provide vivid examples of evolved social systems. He also incorporates data from vertebrate ethology, population ecology, and genetics, and he invokes mathematical reasoning to show how selection can favor particular social strategies. The approach is explicitly comparative: patterns are identified across taxa and then interpreted in evolutionary terms.

Human behavior and culture
Wilson extends sociobiological reasoning to human sociality, arguing that aspects of human behavior, kinship patterns, mating strategies, aggression, and moral sentiments, have evolutionary underpinnings. He discusses the interplay between genetic predispositions and cultural institutions, suggesting that culture can be shaped by, and interact with, evolved tendencies. Wilson presents humans as subject to the same evolutionary forces as other animals, while acknowledging the complex mediating role of learning and social environment.

Reception and controversy
The book provoked intense debate, partly because of its claims about human nature and partly because of perceived implications for social policy. Critics accused sociobiology of genetic determinism and cautioned against simplistic biological explanations for complex human behaviors. Prominent biologists and social scientists challenged aspects of Wilson's interpretation and methodology, sparking public and academic disputes about the proper role of biology in explaining society. Supporters argued that the framework opened productive research avenues and integrated disparate findings under a unifying evolutionary logic.

Legacy
Despite controversy, the book had a lasting impact on the life sciences and social science. It helped catalyze fields such as behavioral ecology and evolutionary psychology, prompting new empirical work on the genetic and ecological bases of behavior and renewed theoretical inquiry into levels of selection and gene-culture interaction. Many ideas from the book were refined, contested, or reformulated in the decades after publication, but its central insistence that evolutionary theory is a key tool for understanding social behavior remains influential.