HUMANS, LIKE MANY of their forebears, are social animals. Their societies are ruled by laws based on a mixture of traditional customs, pragmatic measures, and shared values. How much of this organization is the product of biological evolution, how much of cultural evolution? Science has no definitive answer to this question, but it can contribute certain facts that anyone attempting an answer must take into account.
In 1975, the Harvard zoologist Edward O. Wilson, an expert in social insects, made headlines with a massive, lavishly illustrated opus challengingly titled Sociobiology: The New Synthesis.1 In this ambitious, scholarly work, Wilson reviewed all forms of animal associations, from the lowest colonial invertebrates, such as corals and polyps, to the most advanced primates, paying special attention in each case to the evolutionary factors that might have favored the selection of certain genetically determined social behaviors.
In his approach, Wilson followed, albeit in more detailed and comprehensive fashion, a general tendency of modern ethology, which interprets animal sociality within the framework of Darwinian theory, guided by the principle that evolution selects any genetic trait that leads to a greater frequency of the relevant gene or genes in the gene pool of the species concerned. A lucid account of this approach is given in The Selfish Gene, by Britain's Richard Dawkins.2 This book, published shortly after Wilson Sociobiology, covers much the same ground, but more briefly and in a language entertainingly accessible to the general public. The key point is that animal societies usually consist of related individuals having many genes in common. Members of such societies can propagate their genes in two ways. They can do so by producing offspring, which faculty is said to account for the selection