[Periodic]

All dogs can still interbreed, so they're still the same species. They're different enough from wolves that they're given a different sub-species, sort of like Homo Sapiens Sapiens and Homo Sapiens Neanderthalensis. However, the variety within domesticated dogs is similar to race.

What makes dogs breeds so different is that the dog genome is extremely plastic: it has a lot of room for variation as evidenced by how far pugs have come from wolves, even though theoretically they can still mate and produce fertile offspring.

[richmarr]

> What makes dogs breeds so different is that the dog genome is extremely plastic

Is there evidence that dogs genome is more plastic than humans?

To my (very limited) knowledge we've not tried selectively breeding humans within bloodlines in anywhere near the same way that breeds of dog have been selected. Are there other domestic animals that have recieved the same degree of breeding but not reached such variation?