As a life history characteristic of human females, menopause is universal, it occurs halfway through the maximum lifespan of the species, and it consistently occurs a t approximately age 50 in different populations. Menopause is fundamentally distinct from the reproductive senescence that has been described for a very small number of very old individual alloprimates. Menopause is not a recent historical artifact. As a species universal showing little variation in occurrence across contemporary populations, it must be understood in evolutionary terms. Supporters of the "grandmother hypothesis" explain menopause as an adaptive feature in itself. Others see menopause as a byproduct of the increased lifespan of Homo sapiens. Plieotropy theory may help to explain menopause in broader mammalian terms.In recent years menopause has been increasingly examined from clinical, social, and scientific perspectives. Physical anthropologists have a n approach to menopause that is at once unique and diverse, as it incorporates primatological, historical, cross-cultural, and evolutionary views. While many of us are interested in the menopause, it is clear that physical anthropologists do not share a n interpretation with which all agree. It is common to find confident yet contradictory statements in the literature. For example, menopause is described as being a n illness, and a developmental process; as a uniquely human characteristic, and one shared by the alloprimates; as being a recent historical phenomenon, and a distant evolutionary one; as a primary adaptation, and as a secondary or tertiary by-product.In this paper we provide a n overview of menopause and of controversies in the menopause literature in the hope of giving physical anthropologists the common base of knowledge that is essential to informed theory development. Our general approach throughout the paper is structured by a life history perspective. As DeRousseau recently noted (1990:1), "Life history is a n exciting new direction in evolutionary studies. It focuses attention on the processes and events that occur in the lives of individual organisms, and questions their evolutionary significance." In the case of menopause, we will be stressing three characteristics that make it a significant phenomenon in life history studies of the human female: its universality (virtually every woman who survives into her sixth decade will experience menopause); its relative timing in the overall life course (approximately half-way through the maximum life span of the species); and its age-specificity (an approximate age of 50 years has been widely reported for different populations). Four major questions are addressed.First, what is menopause? To answer this question we begin by defining a variety of relevant terms, including premenopause, perimenopause, postmenopause, climacteric, lifespan, and life expectancy, and we address the sex differences in 0 1991 Wiley-Liss, Inc. [Vol. 34, 1991 reproductive senescence in humans and the misnomer of male menopause. Basic fe...
