The figure shows a simplified phylogeny of closely related species of primates.This tree was proposed by comparing DNA sequence changes in the gene for cytochrome oxidase subunit II.The vertical scale represents time and the branch points represent common ancestors.What species did ancestor B give rise to?
A)Siamangs and orangutans.
B)All of the species except orangutans.
C)All of the species except siamangs.
D)All of the species except siamangs and pigmy chimps.
E)Gorillas,humans,and both types of chimps.

Question

The figure shows a simplified phylogeny of closely related species of primates.This tree was proposed by comparing DNA sequence changes in the gene for cytochrome oxidase subunit II.The vertical scale represents time and the branch points represent common ancestors.What species did ancestor B give rise to? 
A)Siamangs and orangutans. 
B)All of the species except orangutans. 
C)All of the species except siamangs. 
D)All of the species except siamangs and pigmy chimps. 
E)Gorillas,humans,and both types of chimps.

Quizplus · Accepted Answer

Ancestor B gave rise to all of the species except siamangs. The siamangs branched off earlier, before the common ancestor of the rest of the species.

The Figure Shows a Simplified Phylogeny of Closely Related Species