The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

-Which of the five common ancestors, labeled V-Z, has given rise to the greatest number of species, both extant and extinct?
A)V
B)W
C)X
D)Y

Question

The following questions refer to the evolutionary tree in Figure 22.2.
The tree's horizontal axis is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. The labeled branch points on the tree (V-Z) represent various common ancestors. Let's say that only since 50,000 years ago has there been enough variation between the lineages depicted here to separate them into distinct species, and only the tips of the lineages on this tree represent distinct species.

-Which of the five common ancestors, labeled V-Z, has given rise to the greatest number of species, both extant and extinct?
A)V 
B)W 
C)X 
D)Y

Quizplus · Accepted Answer

The branch point labeled X has given rise to the greatest number of species, as it has multiple branches leading to distinct extant and extinct species.

The Following Questions Refer to the Evolutionary Tree in Figure