“This all tells us physiologically how modern humans have changed from their ancestors.” “So, in humans, the nose can become small, because our bodies have smaller oxygen requirements than we see in archaic humans,” Holton says, noting also that the rib cages and lungs are smaller in modern humans, reinforcing the idea that we don’t need as much oxygen to feed our frames as our ancestors. Modern humans have less lean muscle mass, meaning we can get away with smaller noses. The reason, the researchers believe, is because our distant lineages had more muscle mass, and so needed larger noses to maintain that muscle. It also explains why our noses are smaller than those of our ancestors, such as the Neanderthals. This follows the same pattern as energetic variables such as oxygenate consumption, basal metabolic rate and daily energy requirements during growth.” “We have shown that as body size increases in males and females during growth, males exhibit a disproportionate increase in nasal size. “This relationship has been discussed in the literature, but this is the first study to examine how the size of the nose relates to body size in males and females in a longitudinal study,” says Nathan Holton, assistant professor in the UI College of Dentistry and lead author of the paper, published in the American Journal of Physical Anthropology. Prior research has shown that, during puberty, approximately 95 percent of body weight gain in males comes from fat-free mass, compared to 85 percent in females. Physiologically speaking, males begin to grow more lean muscle mass from that time, while females grow more fat mass. The researchers also note that males and females begin to show differences in nose size at around age 11, generally, when puberty starts. Larger noses mean more oxygen can be breathed in and transported in the blood to supply the muscle. The size difference, the researchers believe, comes from the sexes’ different builds and energy demands: Males in general have more lean muscle mass, which requires more oxygen for muscle tissue growth and maintenance. But one feature seems to hold true: Men’s noses are bigger than women’s.Ī new study from the University of Iowa concludes that men’s noses are about 10 percent larger than female noses, on average, in populations of European descent. Human noses come in all shapes and sizes.
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