Clades, clines, clusters. Is only one system valid? Two? All three? None at all?
I’ve heard and seen scientists debate this since around the early 2000s with conflicting answers so I’m really curious to hear what’s the most appropriate take on this topic.
And let me disclaim that obviously human populations are fuzzy categories to begin with.
I don’t even know how to frame the issue as you state it. My knowledge of “clades” is that they’re used to group various sets of species that have something in common that isn’t otherwise represented by classic taxonomy. How… how would that apply to humans, anyway?
As for “clines” and “clusters,” I’m just now learning their meaning in genetics, but they seem to be at considerable variance with each other(!)