Talk about the main distribution areas and physical characteristics of the three major people in the world.

There are many ways to divide human races in the world. At present, China adopts the internationally accepted trisection, which divides human beings into three major races: Mongolian race (yellow race), Europa race (white race) and nigro-Australian race (black race).

① Mongolian race, also known as Asian race or yellow race. The main features are hard, straight and dark hair, yellow and brown skin color, underdeveloped body hair, prominent cheekbones and canthus folds in the eyes. Mainly distributed in eastern and southeastern Asia and the American continent. (2) the European race, also known as Caucasian race or white. The main features are thin and wavy hair, light skin color, well-developed body hair and beard, inconspicuous cheekbones, high nose and thin lips. Mainly distributed in Europe, North Africa, West Asia and North India, and gradually spread to America and Oceania since the 16th century. (3) nigro-Australian race, also known as equatorial race or black race. It is mainly characterized by dark black curly hair, slightly convex jaw, wide nose and thick lips. Generally divided into nigro and Australia, the former is distributed in sub-Saharan Africa, and the latter is distributed in Australia, Oceania and parts of Asia. The mixed types of races were mostly formed in the Middle Ages and modern times. Due to ethnic migration, different races intermarry with each other and form a variety of mixed-race peoples.