>>13574815Black people have flat noses because they evolved in the tropics
Black people have long noses because they evolved in colder weather, but not freezing cold
East Asians have very little noses because they evolved in Siberian freezing cold. Their little eyes also protect them from Siberian cold.
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The reasons Shriver suspects this occurs are similar to those of Woodruff's: In the warm, humid climates where humans first evolved, a wide nose would allow more air to be inhaled with less effort. But as anyone who gets frequent nosebleeds and coughs in the winter could attest, colder, drier air is much more irritating to the membranes of the nose and throat. A more narrow nose will cause more "turbulence" as air is inhaled, mixing the air together inside the nostrils to help warm it like a convection oven, Shriver says.
https://www.smithsonianmag.com/science-nature/how-climate-changed-shape-your-nose-180962567/ 
