Dialogue on Early Humans

Steve Patrick came across an interesting article this weekend: Earliest Human Walking Ancestor Found?

In an effort to expand my archaeological horizons outside of classical and hopewell, I decided to ask a few questions. The following is an email exchange between Mr. Patrick and myself that occurred on Sunday March 6th.

Steve,

This is great stuff. Things I don't know about though... how much does the Tibia offer proof that these are remains of a bi-pedal ancestor to humans?? Is the ancestor part complete speculation?? Can they be certain that their dating methods are accurate--3.8-4 million years old? I don't know much about bones and if dating can be relied upon.

What is it about Africa anyway? I can't remember this from Anthro 200-probably b/c I was sleeping with my eyes open...

"The findings have not been reviewed by outside scientists or published in a scientific journal." This to me is again interesting... will this story fade as other anthro's review and take a look at the bones??

What do you think? You have far more experience in this area than I...

Laura

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Laura,

The tibia is solid proof for bipedalism and if compared with other known ancestors *which is how I'm assuming they came to this conclusion* it is possible to conclude that this is an ancestor as well. If it looks like a duck, then it is a duck, that kind of thing. As far as the dating is concerned... that's probably a good call that it is questionable... Usually dates of these early hominid sites involve dating the geology surrounding the find. It's odd they didn't mention how they came by the date. It'll be interesting to see if this story fades away as you said.
With regards to "what is it about Africa anyway?"... that's just where the earliest hominids have been found. Lucy, footprints at Laetoli, Taung child, etc. There are theories that it all started there and then our ancestors (H. erectus) migrated out from there because of environmental pressures, or just general curiosity. It's also possible that there were multiple points on the earth for human evolution... because there have been some incredibly old finds in Asia which date to when the "migration" should have occurred... so either they were in a big damn hurry or the theory needs tweaked a bit.
Just thought this story on MSN was more interesting than the usual "J. Lo has New Man" type stories... :O)

-Steve
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Steve,

Thanks for your explanation... reminded me of several things I learned long ago now. Interesting that you mention potential problems with migration. A story broke recently--a few months ago?--that similar human ancestor bones where uncovered in South Carolina --which would completely rewrite the timeline of migration and when the first humans arrived in North America. I thought the article a bit odd though, archaeologists where only going off a few bone fragments which to me is completely absurd.

Are there any theories out there at to WHY it all started in Africa? I don't know much about this subject.

Laura
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Laura,

I hadn't heard that about the find in South Carolina... I'd be very interested in checking that out... you'll have to remind me of that later. The best theories about why it started in Africa revolve around either environmental pressures encouraged the evolution of a biped or that there were problems in the ape-world that made it advantageous to use your hands while moving. There are a lot of problems associated with bipedalism as opposed to quadrapeds (backpain, knee and ankle injuries, vulnerability to predators, etc), so there must have been a good reason to switch modes of transportation.

There is a guy up at Kent State named Lovejoy who thought it was a maternal issue... that the mother needed to stand in order to hold her young as they crossed the grasslands. It could also be a matter of perspective... you can get a better look over the savannah to watch for predators if you're standing. At any rate, something made these little guys stand up and walk across the savannah.

In terms of migration, I don't know why we couldn't evolve in several areas... if civilization can develop in six distinct places in antiquity, why can't the same be the case for evolution? However, I do think that the North America thing is a little preposterous... maybe I'm just old-fashioned. :O)

-Steve