We're not used to seeing diversity in humans, as the extant population is remarkably same-ish apart from very extremely minor traits like skin colour or eyelid variations. There's quite a bit of genetic diversity within the African continent, but even there it's remarkable how well we all cluster together, genetically.
So given a fossil record where we find people without chins and broader shoulders, etc. we go crazy with the species boundaries.
But given how rare fossilization conditions are, we're only seeing a tiny fraction of what was out there anyways, so it seems remarkably bold to classify with such confidence.
The reality is that nature doesn't "care" about species. There were likely bagloads of individuals who sat on a continuum of a diversity of traits that have since disappeared because of population bottlenecks at, disease, famine, homogenization, etc.
We're not used to seeing diversity in humans, as the extant population is remarkably same-ish apart from very extremely minor traits like skin colour or eyelid variations. There's quite a bit of genetic diversity within the African continent, but even there it's remarkable how well we all cluster together, genetically.
So given a fossil record where we find people without chins and broader shoulders, etc. we go crazy with the species boundaries.
But given how rare fossilization conditions are, we're only seeing a tiny fraction of what was out there anyways, so it seems remarkably bold to classify with such confidence.
The reality is that nature doesn't "care" about species. There were likely bagloads of individuals who sat on a continuum of a diversity of traits that have since disappeared because of population bottlenecks at, disease, famine, homogenization, etc.