What does recent evidence from molecular systematics reveal about the relationship between grades and clades?
A) There is no relationship.
B) Some, but not all, grades reflect evolutionary relatedness.
C) Grades have their basis in, and flow from, clades.
D) Each branch point on a phylogenetic tree is associated with the evolution of a new grade.

Question

Quizplus · Accepted Answer

Recent evidence from molecular systematics shows that some grades, which are groups of organisms sharing similar levels of complexity or adaptation, do not necessarily reflect true evolutionary relationships, while others might. Clades, on the other hand, are groups that include an ancestor and all its descendants, reflecting evolutionary relatedness.

What Does Recent Evidence from Molecular Systematics Reveal About the Relationship