Currently, two extant elephant species (X and Y)are placed in the genus Loxodonta, and a third species (Z)is placed in the genus Elephas. Thus, which statement should be true?
A) Species X and Y are not related to species Z.
B) Species X and Y share a greater number of homologies with each other than either does with species Z.
C) Species X and Y share a common ancestor that is still extant (in other words, not yet extinct).
D) Species X and Y are the result of artificial selection from an ancestral species Z.
E) Species X, Y, and Z share a common ancestor, but nothing more can be claimed than this.

Question

Quizplus · Accepted Answer

Since species X and Y are placed in the same genus, they share a greater number of homologies with each other than either does with species Z. This choice is the best fit. Choice A is incorrect because all three species share a common ancestor. Choice C is also incorrect because the common ancestor of species X and Y is no longer extant. Choice D is incorrect because there is no evidence of artificial selection in the origin of these species. Choice E is too general and does not address the relationship between the species in question.

Currently, Two Extant Elephant Species (X and Y)are Placed in the Genus