One of the biggest stereotypes about men is that stopping to ask for directions is some kind of affront to their manhood. What is so innately important about having a good sense of direction? A new study suggests that better navigational skills could be tied to reproductive success, as men who can travel further than others will find more mates and sire more children. The research was conducted by Layne Vashro and Elizabeth Cashdan from the University of Utah, and the paper has been published in the journal Evolution & Human Behavior.
In most mammalian species, males occupy a larger range than females and are polygynous, meaning they reproduce with a multiple mates. This generally means that they have superior navigational and spatial skills compared to females. Cashdan and Vashro wanted to explore if this held true in humans and if there was an evolutionary component.
”Among the most consistent sex differences found in the psychological literature are spatial ability and navigation ability, with men better at both,” Vashro said in a press release. “In the anthropological literature, one of the most consistent behavioral differences between men and women is the distance they travel. This difference in traveling is assumed to explain the observed differences in spatial ability and navigation ability. Now, we’ve drawn a link between spatial ability and range size.”
The research utilized men and women from the Twe and Tjimba tribes in Namibia. These two groups were ideal because their cultures include a great deal of foraging, traveling through the mountains on foot, and procreation is not exclusive to monogamous relationships. These conditions are very similar to how ancient humans lived, which is a better model for the evolutionary basis of their hypothesis.
The participants mentally rotated objects on a computer to test their spatial skills, and was asked to point to distant locations to test navigational abilities. Cashdan and Vashro then determined each person’s range based on how many miles each person had walked and how many locations they had visited over their lifetime and within the last year. The men were also asked how many children they have fathered during their lives.
As it turns out, men performed significantly better at the mental spatial exercises and the navigation test than women. The men also averaged a 30 mile range with visits to 3.4 locations within the last year, while women had a range of 20 miles and only visited 2 locations per year.
While there was no statistical correlation between range size and spatial test score between women, the researchers found that men who performed better on the spatial tests generally had larger ranges than men who did not perform as well. Additionally, the men with the largest ranges also had the most amount of children, likely due to an increase in opportunity.
The researchers are treading carefully with these results, referring to correlation rather than causation between navigation skills and reproduction. Paternity was not verified with the children claimed with the men, which could be a potential confounding factor in this study.
[Header image: Otto Phokus via Flickr]
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