A phylogenetic tree that is "rooted" is one
A)that extends back to the origin of life on Earth.
B)at whose base is located the common ancestor of all taxa depicted on that tree.
C)that illustrates the rampant gene swapping that occurred early in life's history.
D)that indicates our uncertainty about the evolutionary relationships of the taxa depicted on the tree.
E)with very few branch points.

Question

Quizplus · Accepted Answer

A rooted phylogenetic tree is one in which the base represents the common ancestor of all the taxa depicted on the tree. This provides a framework for understanding the evolutionary relationships among the different taxa. Option A is incorrect because a rooted tree doesn't necessarily extend back to the origin of life on Earth. Option C is incorrect because a rooted tree doesn't necessarily illustrate gene swapping. Option D is incorrect because a rooted tree provides a clear picture of the evolutionary relationships of the taxa depicted on the tree. Option E is incorrect because a rooted tree can have multiple branch points, as it shows the relationships between different species.

A Phylogenetic Tree That Is "Rooted" Is One