Dogs are the same species, but come in all shapes and sizes and colours. Horses are all the same species but come in different sizes and colours. When you consider the human species, we all look much more alike, I think, than a bull mastiff and a chihuahua, (but there are pygmies, and there are pro basketball players). Biologically speaking, within one species, there can be so much lovely, beautiful diversity, we could look around us in awe and should be inspired to be curious and kind, (like @Coloma s animals) but instead, we humans react more with fear and suspicion. Doesn’t really represent well of our species, does it?
Actually, there are animals that are of the type of species called ‘ring species’ meaning that those that live near eachother can breed successfully, but the further apart they get, geographically, the less they get along and the more different they are biologically and they finally get to the point where the are so different genetically, they can no longer breed together. In some species this can occur quickly when geographically separated, and breed isolated for a time (Australian Possum vs NZ Possum). For humans, we are so similar, even though we are geographically separated for many many generations, we can successfully, not only get along, but also have viable and beautiful offspring. I like to think that our similarities, genetically speaking, stand up to the test of time and genomic differences.