Consider five species of toads (A-E).Species A and B are sister species.Species C and D are also sister species.The clade containing species A and B is a sister to the clade containing species C and D.Not counting the root as a node, how many nodes would be found in a phylogenetic tree of species A, B, and C?
A) One
B) Two
C) Three
D) Four
E) Five

Question

Quizplus · Accepted Answer

In a phylogenetic tree of species A, B, and C, there would be two nodes. One node represents the common ancestor of A and B (since they are sister species), and the second node represents the divergence point from species C. Species C, being outside the clade that includes A and B, adds no additional nodes in this context.

Consider Five Species of Toads (A-E)