They can be aquiline, narrow, bulbous, or turned-up. They can be runny, itchy, or red. There’s no doubt that the human nose is a distinctive facial ornament, and every person’s nose is unique. And while you know that you inherited your nose shape from your parents, a new genetics study suggests that your ancestors’ climate may have played a role in shaping your sniffer.
Researchers studied three-dimensional images of the noses of hundreds of people of Northern European, South and East Asian, and West African descent. They also looked at the climate in the areas where these different racial groups originated and were able to conjecture that temperature and humidity played an important role in deciding nose shape.
Your nose is for more than smelling scents. It also helps control the temperature and humidity of the air you breathe, which is why one’s local climate might have helped determine nose shape. At the dawn of the human age, before we had air conditioners and dehumidifiers, the construction of your nose may have helped to determine your ability to survive to adulthood and produce offspring.
People with narrower nostrils, like those of Northern European ancestry, can more efficiently humidify and heat up the air they breathe. This would make narrow nostrils a beneficial adaptation in climates with colder, drier air, as is found in places like Scandinavia. The opposite climactic conditions would have made wider nostrils more effective in places nearer the equator, where the air is hotter and more humid.
Though climate seems to have been important in shaping the nose, it was probably not the only factor at play in the matter. Sexual selection certainly played a role as well, and people would have chosen breeding mates based on local beauty ideals. These would have varied from region to region, and are much harder to study since millennia have passed since humans first began to spread around the globe. We do know that sexual selection must have been important, however, because the researchers also found large differences between male and female nose traits.
Scientists hope that this research may have practical applications in the field of crime victim identification. It is difficult to deduce a victim’s nose shape accurately when only skeletal remains are left. With this new knowledge, investigators may be able to more accurately determine what a victim looked like based on DNA. There is also a possibility that DNA left behind at crime scenes may help the police to figure out what a perpetrator looks like, although more research is needed as nose shape is only a fraction of a person’s appearance.
The scientists who conducted the study have conceded that there may be other factors that helped influence nose shape in different populations and are interested in further study of human adaptation due to ecological influence. But the science of how human environments can influence genetics is fascinating, and there will certainly be future research in this area.