If the definition of species is that individuals of the same species are capable of producing fertile offspring why were humans and Neanderthals able to reproduce? Are we the same species?

Question

If the definition of species is that individuals of the same species are capable of producing fertile offspring why were humans and Neanderthals able to reproduce? Are we the same species?

In: Biology

Answer 1

Yes, for this reason, Neanderthals are often referred to as a subspecies of human with the classification of Homo sapiens neanderthalensis, as opposed to our classification of Homo sapiens sapiens.

But this does also demonstrate a more common theme that species classification is hard and nature isn’t designed to be put into nice boxes.