There are two opposing views about origin of modern man. According to one view Homo erectus in Asia were the ancestors of modern man. A study of variation of DNA however suggested African origin of modern man. What kind of observation of DNA variation could suggest this

There are two opposing views about origin of modern man. According to one view Homo erectus in Asia were the ancesstors of morden man. A study of variation of DNA however suggested African origin of morden man. What kind of observation on DNA variation could suggest this?

What was the most significant trend in the evolution of modern man (Homo sapiens) from his ancestors ?