Believe it or not, processing smell is not the essential function of your nose. 

(Photo: Flickr/Paulscott56)
We've had it since we were born. It sits right on our face. But how much do we really know about our nose?

The size, according to new research, depends on your sex. Even men and women of the same physical size most likely have different-sized noses.

The nose size for a man is, on average, 10 percent bigger. Why? Because men tend to have 10 percent more lean muscle mass, which requires more oxygen.

Anthropologist Todd Yokley is a professor at Metropolitan State University of Denver, which co-authored recent findings that unearth several other curious facts about the nose. But perhaps this is the most suprising among them: smelling is not our nose's primary function.

So, then what is? The most important role for the nose is actually to warm and humidify air inhaled by the lungs.

That essential function makes climate yet another factor that influences one's nose shape and size. Ethnic groups that are native to colder, drier parts of the world tend to have different noses than those from warmer, moister regions.