In matters of sex and death, men are an essential part of the equation

Aug 29, 2007

In a paper, to appear in the August 29 issue of the online, open-access journal PLoS ONE, Stanford scientists show that the standard practice of tracking only female life histories leads to mistaken conclusions about the forces that shape human evolution. The reason is that men's and women's age patterns of fertility differ in important ways.

Stanford scientists show in a forthcoming paper that traditional mating patterns make men the key to explaining away the “wall of death,” an enduring puzzle in the study of human longevity.

The paper, to appear in the August 29 issue of the online, open-access journal PLoS ONE, proposes a solution to a conundrum in the study of human lifespan: why don’t we drop dead soon after the age of last female reproduction" Our understanding of the evolution of lifespan suggests that we have no defense against mutations that occur after we reach the end of our reproductive lives. As a result we expect a rapid increase in mortality -- a “wall of death” -- just after female menopause.

The authors show that the standard practice of tracking only female life histories leads to mistaken conclusions about the forces that shape human evolution. The reason is that men’s and women’s age patterns of fertility differ in important ways.

The paper brings together data from hunter-gatherer populations to show that male reproduction begins and ends later than women’s, and declines much more gradually. In many populations, historically and even today, some fraction of men continue to father children into their 60s and 70s with younger women.

In some groups, most notably Australian aboriginal and African polygynous societies, late-age male reproduction is common. In many hunter-gatherer societies, which may tell us most about how our ancestors once lived, men begin to reproduce a few years later than women of the same age and they typically continue to father children for several years after the age of female menopause due to the marriage gap in the ages of couples.

The marriage gap, in which older men marry younger women, appears to be a near-universal human trait.

Source: Public Library of Science

Explore further: Research shows loss of pollinators increases risk of malnutrition and disease

add to favorites email to friend print save as pdf

Related Stories

Helicopter parenting better for pets than for kids

Jan 14, 2015

Helicopter parenting may not be the best strategy for raising independent kids. But a healthy measure of clinginess and overprotectiveness could actually be advantageous when rearing dogs and cats, according to new research ...

Men want commitment when women are scarce

Jan 13, 2015

The sexual stereotype, in line with evolutionary theory, is that women want commitment and men want lots of flings. But a study of the Makushi people in Guyana shows the truth is more complex, with men more ...

Drone market resembles Silicon Valley's early days

Jan 07, 2015

To see the future of drones, head up the hill at the intersection of Industrial Drive and Electronics Avenue. Inside a bland brick office building, the team at CyPhy is working on tethered machines that can ...

Recommended for you

Researchers find unusually elastic protein

2 hours ago

Scientists at Heidelberg University have discovered an unusually elastic protein in one of the most ancient groups of animals, the over 600-million-year-old cnidarians. The protein is a part of the "weapons system" that the ...

Obama recommends extended wilderness zone in Alaska

17 hours ago

US President Barack Obama said Sunday he would recommend a large swath of Alaska be designated as wilderness, the highest level of federal protection, in a move likely to anger oil proponents.

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.