Questions about Hominid Fossil classification

Yitzhak Rabin

I have a few questions that a few of the better qualified people around here might be able to answer.

It relates to how they group species of hominids. Particularly the 'youngest' ones. How can they know that they are separate species? Ones like Antecessor, Heidelbergensis, Rhodesiensis, etc. Apart from them being dated to be considerably older, what traits make them non-human? Given the rarity of fossilization, could alot of these fossils fall within the natural range of one species.

Say, for example, a large and hardy African miner was found fossilized in the future and was compared to the fossilized remains of a slight chinese office worker who was considerably smaller. I'd imagine the african, biologically would be alot bigger. The nature of his work would have made his bones alot denser. In comparison, the chinese guy would have been biologically much slighter. His work would have meant thinner bones etc. Also IIRC asians, have a different jaw structure.

Would a scientist knowing absolutely nothing about them, know they were the same 'species'?

Then there is also the case of say, African and Asian pygmies. They would look radically different in fossilized form.

Also I have heard that in comparison, humans are not very genetically diverse. So could it be the case that a lot of these different species, could be one and the same, they just have a deeper gene pool?

Anyway, so, I suppose, I'm basically asking, what criteria do Paleontologists use to differentiate between the species?

Wibbs

I agree about the confusion. Especially given the dearth of fossils. I suspect many so called different species are actually different members of the same species or different genders of the same species(without a pelvis you cant tell). "Oh look this tooth is smaller, that must mean a different species". Eh. No. I recall reading a report on the Erectus findings in Georgia and they found that the males appeared to be significantly more robust than the females in that population. Like you say, moderns can vary a lot and if we only had 5 o 6 partial skeletons, our view of who we were and how we looked and how we related to each other would be a tenuous science at best. And this is with a species like us that are incredibly closely related, nay inbred.