Hostname: page-component-848d4c4894-pftt2 Total loading time: 0 Render date: 2024-05-17T21:44:54.661Z Has data issue: false hasContentIssue false

BIRTH INTERVAL AND THE SEX OF CHILDREN IN A TRADITIONAL AFRICAN POPULATION: AN EVOLUTIONARY ANALYSIS

Published online by Cambridge University Press:  01 October 1997

RUTH MACE
Affiliation:
Department of Anthropology, University College London, Gower Street, London WC1E 6BT
REBECCA SEAR
Affiliation:
Department of Anthropology, University College London, Gower Street, London WC1E 6BT

Abstract

Birth interval is a major determinant of rates of fertility, and is also a measure of parental investment in a child. In this paper the length of the birth interval in a traditional African population is analysed by sex of children. Birth intervals after the birth of a boy were significantly longer than after the birth of a girl, indicating higher parental investment in boys. However, in women of high parity, this differential disappeared. Birth intervals for women with no son were shorter than for those with at least one son. All these results are compatible with an evolutionary analysis of reproductive decision-making. First born sons have particularly high reproductive success, daughters have average reproductive success and late born sons have low reproductive success. The birth interval follows a similar trend, suggesting that longer birth intervals represent higher maternal investment in children of high reproductive potential.

Type
Research Article
Copyright
© 1997 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)