Question

On the assumption that humans and chimpanzees last shared a common ancestor 6 million years ago (6 Mya), when did modern humans and Neanderthals last share a common ancestor? Your data are the mitochondrial genome sequence differences and the tree inferred from those numbers of substitutions, on the slide near the end of Jon's lecture # 4 (L4). Please give your answer in units of millions of years, to the nearest tenth of a million (i.e., in the form X.Y). The human reference genome is 16,569 base pairs long.

The evolutionary relationships of these four species can be inferred from the matrix of pairwise nucleotide differences. mod Nea chi gor - - - - node 1 br 2 br 1 modern human (m) - 168 1305 1605 Neanderthal (N) 168 - 1290 1597 chimpanzee (c) 1305 1290 - 1557 gorilla (g) 1605 1597 1557 - node 2 br 4 br 3 And also from the distribution of site patterns. m Nog mncg 6 million lears. - - # 10 884 589 583 63 G 53 TT p1 1 1 1 2 т т т с p2 1 1 2 2 A ACC p3 1 1 2 1 тест p4 1 2 2 2 p5 1 2 1 1 p6 1 1 2 3 СА p7 1 2 2 1 TC p8 1 2 1 2 TC p9 1 2 2 3 G C p10 1 2 3 3 p11 1 2 1 3 TCTA p12 1 2 3 2 G C A C node 3 | br 5 br 6 OHUR HUHR 4 Tc 2 2 1 m P N g - - - - - - - - 2264

Answer 1

Neanderthals belong to our closest extinct humans as relative families. Few facial features of skulls comprehend the huge middle portion of face, angled bones of cheeks, and large nose. Neanderthals bodies were shorter than mmodern humans and were adapted to live in cold conditions. But relative brains size was just large as ours. The modern humans and Neanderthals last share a common ancestor for about 70 million (700,000) and (30 million ) 300,000 years ago. Modern humans and Neanderthals belong to related genus (Homo) and resided in areas of western Asia for about 30,000–50,000 years and evidences from genetics illustrate that they cojoin with non-African humans.