According to a new study, men have bigger noses than women by as much as 10 percent on average for people of European descent.

Nathan Holton, assistant professor in the University of Iowa College of Dentistry and lead author of the study, concluded that this size difference is due to male bodies being larger than female bodies on average, thus causing nasal passages in males to grow to help bring oxygen to the male's body. As Holton explains to Science Daily:

"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...We have shown that as body size increases in males and females during growth, males exhibit a disproportionate increase in nasal size. This follows the same pattern as energetic variables such as oxygenate consumption, basal metabolic rate and daily energy requirements during growth."

The scientist went on to explain that the difference in nose size begins around the age of 11. When boys and girls begin puberty, boys tend to grow more muscle mass, which in turn requires more oxygen. Holton says that even in same-sized subjects males have bigger noses:

"Even if the body size is the same...males have larger noses, because more of the body is made up of that expensive tissue. And, it's at puberty that these differences really take off."

The nose's growth is a biological response to this need that was developed in our ancestors. This also explains why other ancient humans such as Neanderthals had larger noses, as they had more muscle mass that needed oxygen in comparison to ancient homo sapiens:

"So, in humans, the nose can become small, because our bodies have smaller oxygen requirements than we see in archaic humans...This all tells us physiologically how modern humans have changed from their ancestors."

The data for the study was taken from 38 subjects of European descent as part of the Iowa Facial Growth Study. The subjects were studied from three years of age until their mid-20s at regular intervals. Holton believes that the data would be supported with different ethnic groups, but cautions that further study is needed to confirm this.