Asked by: Anonymous
With two uncovered holes the rain would get in. Our cousins the gorilla and chimpanzee have much flatter noses, but they don't spend nearly as much time upright as we do, so they don't need such a large nostril umbrella. Aside from protecting us from rain showers, our noses may have evolved to cope with the much drier environment of the African savannah. As well as being used for breathing and smelling, the nose acts as a heat and moisture exchanger. This reduces the humidity of the air we breathe out, thereby conserving water in an arid climate. Baboons, which also live in the savannah, have long nasal passages too.
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