Also, dog breeds exist because humans have actively bred dogs to have certain traits
Selection pressure is selection pressure, whether being done by environment or by the active efforts of another species. There's a reason why whether or not you are lactose tolerant has a lot to do with where in the world your ancestors are from, as does your likelihood of several diseases and likelihood of certain resistances/immunities, there are even certain drugs that will work better or worse for people dependent largely on where their ancestors came from. Short of doing thorough genetic testing, "race"/ethnicity is often a good-enough broad brush proxy for where a majority of your ancestors came from for a variety of purposes.