Collapse: How Societies Choose to Fail or Succeed

by Jared Diamond

On Tikopia, however, people are explicit in saying that their motive for contraception and other regulatory behaviors is to prevent the island from becoming overpopulated, and to prevent the family from having more children than the family’s land could support. For instance, Tikopia chiefs each year carry out a ritual in which they preach an ideal of Zero Population Growth for the island, unaware that an organization founded with that name (but subsequently renamed) and devoted to that goal has also arisen in the First World. Tikopia parents feel that it is wrong for them to continue to give birth to children of their own once their eldest son has reached marriageable age, or to have more children than a number variously given as four children, or one boy and a girl, or one boy and one or two girls.