They may be called black because they're dark, but other than dark skin they don't really resemble Africans in general. Maybe you can find individual Africans who resemble individual Aborigines, but they have some significant differences in their phenotype. But I can see some vague similarity with some of the Mbutid influenced people (Although from a quick glance they seem more like Melanesians in their looks, imho). Any similarity is otherwise very vague, imho. If they're considered Black due to dark skin, then all people with really darks skin can be called "black" - and that also means that any light skinned black aren't black, if such a literal interpretation of the term is used.