The Thammasat University Library has acquired a new book that should be useful for students interested in anthropology, evolutionary psychology, sociology, medicine, culture, evolutionary biology, and ethnography.

The Slow Moon Climbs: The Science, History, and Meaning of Menopause is by Professor Susan Mattern, who teaches history at the University of Georgia in the United States of America.

Her book on the evolution of menopause describes how anthropologists have concluded that older women make valuable contributions to their community and families.

The TU Library collection includes several books about different aspects of menopause. 

Previous researchers claimed that after they no longer have children, women’s significance decreases. More recent research indicates that menopause, when a woman is no longer able to become pregnant naturally, is not a loss or deficiency.

The book’s title is a quotation from Ulysses, a poem by Alfred, Lord Tennyson about middle age:

The long day wanes; the slow moon climbs…Come, my friends,/’Tis not too late to seek a newer world…The end of Eden was the beginning of the world as we know it. Go forth and build worlds.

The TU Library also owns books by and about Tennyson. Professor Mattern encourages menopausal women to go forth and build worlds.

Anthropologically, older women are essential as caring grandmothers, to help ensure that children will survive.

Menopause is

part of a reproductive strategy that allows us to breed quickly while also investing in long-lived, high-quality offspring — a system that is . . . resilient in periods of stress; that can ‘boom’ in good ecological conditions.

In some traditional communities around the world, older women outnumber older men and gather more food than others.

Historically, older women have been highly productive while not bringing any more children into communities who need to be fed.

Culturally, there has been significant confusion about the meaning of menopause to society in general, with much negativity directed toward individuals. This is a recent development, and a misguided one.

Professor Mattern concludes that women become non-reproductive so that we can do other things.

Menopause is part of an extraordinary ability to cooperate” that has been “critical to humans’ success.

As the Australian author and feminist Germaine Greer wrote in The Change: Women, Aging and the Menopause (1991):

Women over fifty already form one of the largest groups in the population structure of the western world. As long as they like themselves, they will not be an oppressed minority. In order to like themselves they must reject trivialization by others of who and what they are. A grown woman should not have to masquerade as a girl in order to remain in the land of the living.

Professor Mattern writes,

Today, most women I know think of menopause as a medical problem, to be endured stoically or managed with drugs. Thousands of books offering medical advice on menopause are available, their prescriptions confusing and conflicting at best, and sometimes downright misleading. This book is not one of them. Menopause only became a subject of medical interest in Europe in the eighteenth century, and its place in modern medicine rests on that recent foundation. For most of human history, people have seen menopause for what, as I argue, it really is: a developmental transition to an important stage of life; not a problem, but a solution. For the most part, they have had no word for menopause and have not paid too much attention to the end of menstruation, instead recognizing midlife as a transition to the status of elder, grandmother, or mother-in-law. A great deal of scientific research has tried to solve the puzzle of menopause: Why do women stop reproducing in midlife when it seems obvious that natural selection should have favored those who continued to have children? The explanations that this research has produced are ingenious and fascinating, but mostly inaccessible to the public, and they have had little impact on the popular understanding of menopause— or on that of the medical community, for that matter.

So how did menopause evolve? It emerged and endured in a context of sharing and cooperation—and in this context, it was very useful. The ways in which it proved adaptive might be hard to model mathematically or trace with survivorship studies or by other means, but this does not bother me too much: nature has done the math for us. By helping their daughters to reproduce, grandmothers were part of a system that allowed humans to compress 50 years of reproductive life into half that time, and this factor has helped maintain the balance point of fertility’s end in our 40s, rather than selecting for late-life reproduction in women, which would surely have happened otherwise.

Among humans, because children remain dependent for a long time and are born in rapid succession, the ratio of adults to children in any residential band of foragers is a matter of critical importance to the group’s survival. If families with many small children run caloric deficits, too many dependent children can put the whole group in caloric deficit. Groups can be rebalanced by exchanging members, but a family with many dependent children and few adults might not be welcome in any group. In such conditions, longer weaning periods and much greater spacing between births might be advantageous, and ecology does influence these factors: the !Kung, who inhabit an environment that barely supports them, have longer birth intervals and fewer children than foragers in environments with more abundant food (although a direct relationship between these factors is hard to prove). But in general, it is a distinctive feature of humans that birth intervals are shorter than those of our nearest relatives; women are more fertile in youth, a quality that has allowed for rapid expansion of the population in favorable environments.

In this situation, it is easy to imagine how a woman who stops reproducing in midlife might not have much of a fitness disadvantage over one who keeps bearing children. A woman who kept reproducing throughout her lifespan would produce competitors to her other children and grandchildren for the share of food brought in by adults, while her own productivity would be lower as long as she was nursing infants. Her family would remain in caloric deficit for a much longer time, probably until the end of her life. Older children might help raise her young ones—siblings provide childcare in many forager societies today—but soon after they were able to feed themselves they would start producing dependent children of their own. The group might struggle to provide for her children and for the other children in the camp, and this family would not be able to provide for itself without the group.

(All images courtesy of Wikimedia Commons)