Until recently, the myrtle warbler and the Audubon’s warbler were thought to be separate species of birds because the males have very different appearances. Which of the following observations most likely led to the reclassification of these warblers as one species?

Question

Answer: D - The myrtle warbler and the Audubon’s warbler interbreed and produce fertile offspring.

Ted Chan · Accepted Answer

The myrtle warbler and the Audubon’s warbler interbreed and produce fertile offspring.

CLEP Biology Practice Exam