On average, men are larger than women. But their tendency towards bigger noses—which are about 10 percent larger than women’s—turns out to have a hidden evolutionary purpose. Bigger noses, new research finds, are needed in order satisfy the higher energetic needs of men’s bodies, especially during puberty.
Nose sizes begin to diverge between the sexes around age 11, or just as kids begin to enter into puberty. During that time, the researchers explain, women tend to accumulate fat mass, while men’s bodies build muscle. This trend remains the same throughout life, as adult men, in general, have more lean muscle than women.
The researchers investigated these differences in a long-term study of 40 girls and boys. Between the ages of 3 and 20, the team took detailed measurements and X-rays of their subjects’ bodies. Nose size in the boys increased at a disproportionate rate to body size compared to the girls, NBC New reports. ”Even if the body size is the same, males have larger noses, because more of the body is made up of that expensive tissue,” the researchers explain in a statement.
The team concluded that those differences likely evolved because a bigger schnoz can suck up more air than a dainty one, and it takes a greater supply of oxygen to power the excess of energetically demanding muscle that men have, compared to women. This also speaks to differences between modern humans and our ancient ancestors, the researchers say. Ancient humans had more muscle mass than we soft creatures of today, and thus needed extra-large noses.
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