Men have bigger noses than women because they have more muscle

Men have bigger noses than women, and it's due to the sexes' different builds and energy demands, researchers at the University of Iowa say. Males in general have more lean muscle mass, which requires more oxygen for muscle tissue growth and maintenance, they said, and larger noses mean more oxygen can be breathed in and transported in the blood to supply the muscle. "We have shown that as body size increases in males and females during growth, males exhibit a disproportionate increase in nasal size," researchers Nathan Holton said in a university release Monday. Males and females begin to show differences in nose size at about age 11, generally when puberty starts, the researchers said, Physiologically speaking, they said, males begin to grow more lean muscle mass from that time, while females grow more fat mass. "This follows the same pattern as energetic variables such as oxygenate consumption, basal metabolic rate and daily energy requirements during growth," Holton said. It also explains why our noses are smaller than those of our ancestors, such as the Neanderthals, he said, because our distant lineages had more muscle mass and needed larger noses to maintain that muscle. "So, in [modern] humans, the nose can become small, because our bodies have smaller oxygen requirements than we see in archaic humans," Holton said. Rib cages and lungs are also smaller in modern humans, reinforcing the idea that we don't need as much oxygen to feed our frames as our ancestors did, he said.