Evolution of different species in a given area starting from a point and spreading to other geographical areas is known as
adaptive radiation
natural selection
migration
divergent evolution.
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 on $DNA$ variation could suggest this
Mesozoic era is called the
Contribution of scientist : August Weismann