Something I've never understood (since highschool some 30 years ago) is; when getting partial skeletons perhaps from only a single individual, how can they claim new species? I mean what's diff with that and some hypothetical future anthropoligist looking at siberian with roundish skull thicker brow ridges and that of six foot tall masai with long face and then a sub 5 foot native peruvian and declaring them all diff…
Consider that "spanish" and "italian" are officially separate languages, while the US and Scotland both officially speak "english". The terminology won't help you predict which pair has an easier time communicating. It's political.