Question 11

(Multiple Choice)

Can two different species that are members of the same clade have more than one common ancestor? Choose the MOST correct answer and explanation.


A)No.Because they are members of a clade,by definition they can have only one common ancestor.
B)Maybe.Two species in the same clade can have more than one common ancestor only in cases where horizontal gene transfer from a third,previously unrelated,species has occurred.
C)Maybe.If they are members of a clade that is not monophyletic,they can have more than one common ancestor.
D)Yes.Although two species in the same clade have only one most recent common ancestor,they also have a number of older common ancestors that occurred earlier in their evolutionary history.
E)Yes.Two species of the same clade always have eight common ancestors,matching the number of levels higher than species in the taxonomic hierarchy.

Answer