1. which of the following supports the theory that all modern human populations are descended from a single ancestral population that emerged in africa? a. comparative molecular studies trace our earliest genetic material to africa. b. stone tools found in sediments coeval with the earliest h. ergaster (just under two million years ago) are essentially identical with those made by the first stone toolmakers many hundreds of thousands of years before. c. h. erectus evolved in eastern asia at quite an early date and one branch of the species migrated back to olduvai in africa. no human fossils are associated with the first stone tools known, from sites in \kenya and ethiopia.