Dogs (Canis lupus familiaris) and gray wolves (Canis lupus) can interbreed to produce viable, fertile offspring. These species shared a common ancestor recently (in geologic time) and have a high degree of genetic similarity, although their anatomies vary widely. Judging from this evidence, which two species concepts are most likely to place dogs and wolves together into a single species?
A) ecological and morphological
B) ecological and phylogenetic
C) morphological and phylogenetic
D) biological and morphological
E) biological and phylogenetic
Answer: E