Question

how the gradual adaptation from primitive man to modern man must have taken place

Answer 1

The gradual adaptation from primitive man to modern man has taken place through a wider process called Evolution. Actually adaptation is a part of Evolution. Evolution had led has various development both as physically as well as socially. Physical development like bipedal locomotion , erectile postures , improved eyesight , digestion metabolism.
Social development like settlement , sense of belonging , hunter to settler.
Humans had adapted themselves according to changing climate of a particular area or according to geographical features of the place where they have migrated.
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