Why is a domestic rabbit unable to breed with a wild cottontail?

Question

Forgive my scientific ignorance. For a few years there has been a feral domestic rabbit frequenting my backyard. (photograph below) She is most likely an escapee or a released pet. She hangs out with the wild eastern cottontails.

Every bit of expert information says that wild and domestic rabbits cannot hybridize. Yet now I am seeing other black bunnies! Why can canines, bovines, felines, equines and bears interbreed (i.e. wolf/dog, polar/grizzly, lion/tiger, holstein/buffalo, etc.) but not rabbits?

Answer 1

Usually, only animals within the same genus can interbreed - e.g. lions and tigers both belong to the genus Panthera, horses and donkeys to the genus Equus, etc. Domestic rabbits are descended from the European wild rabbit, Oryctolagus cuniculus. Eastern cottontails are a different species in a different genus, Sylvilagus floridanus. Whilst there are cases of inter-genus hybrids occurring, this is rare, and the offspring are invariably sterile. Melanism - an excess of dark pigment, causing an almost totally black coat - can occur in any species, so it's possible the black rabbits you're seeing are simply melanistic individuals.

Answer 2

Very interesting!  They are different species, even different genus, but I've discovered that this doesn't always prevent hybridization.  The offspring would probably be sterile, but perfectly capable of living a normal life.  And I have seen a black feral rabbit grazing along with cottontails, too.

I have a pigeon (genus columba) that has produced offspring with a ringneck dove (genus streptopelia).  Believe me, I was surprised; but the only other birds in the enclosure were quail!

Domestic rabbits belong to the genus oryctolagus; cottontails belong to the genus silvilagus.  But it seems to me within the realm of possiblility that they could produce offspring.

That's a very pretty bunny.

Answer 3

That snooty domestic bunny thinks it to good to breed with any old wild rabbit.