Saturday, March 3, 2012

We Found the Hominids But Where Are the Chimpanids?


In searching to better understand the intelligent design/evolution debate I’ve come across many different arguments – all making good points as well as making questionable ones. I was having a hard time deciding exactly what to focus on.While immersing myself in this debate I've also been researching for another project dealing with Neanderthals – precursors to humans (or so the evolution theorists say). In researching these hominids and other proto-humans I thought what of chimpanzees? do they, too, have proto-chimpanzees – (chimpanids I’ll call them)?

According to evolutionary biologists, at one moment in time there existed a common ancestor of the chimpanzee and the modern human. After a long period of time a split formed – proto-human going its way and proto-chimpanzee going its way (5 to 8 million years ago). So far scientists have discovered skeletal remains of hominids leading up to the modern human but what of chimpanids leading up to the modern chimp?

Here I had finally found a question I had never considered!

I began searching then for any information on the evolutionary development of the modern chimpanzee – surely they have a similar amount of fossils to that of the hominid fossils, or at least a couple suggesting a gradual change from common ancestor to modern chimp.

In searching I found an article about such fossils. The find happened in 2005 (6 years ago); and the discovery? Teeth. 500,000 year-old teeth are the first known chimpanzee fossils.

It is impossible to tell if these teeth belong to modern chimpanzees or some proto-chimpanzee – a species long extinct. If it is the case that those teeth belong to a modern chimpanzee, then these chimps have been around quite a long time. The modern human has been around for only 200,000 years while an ancestor of the modern human, Homo erectus, had lasted about 1 million years.


With this find another question emerged: did the human-chimp separation happen do to physical separation as previously believed?

Prior to this discovery the main theory suggested that “chimps never crossed east of the Rift Valley, but instead stayed in the jungles of western and central Africa.”  However the chimp remains found were east of this divide. This discovery not only calls into question the cause of separation between humans and chimps evolutionarily but it also undermines the theory of how humans evolved bipedalism – the previous claim being that because proto-humans lived in a savannah bipedalism was a necessary adaption; Yet here scientists have found chimps living in these semi-arid conditions as well.

So what does all this have to do with the intelligent design/ evolutionary debate? I suppose it is another unanswered question in the evolutionary theory. Intelligent design can explain this problem by simply stating there was no divide to begin with. There were separate species already made – unrelated to one another except for the “fact” that they came from a designer. There was no proto-chimp or proto-human – just different species of non-human. Then, an intelligent designer created the first humans. There was no gradual change of one species of hominids into Homo sapiens. All of this of course is speculation as there is no evidence of this intelligent designer like there is the fossil record for evolution (although one could argue the fossil record has little evidence of gradual change).

human ancestor

Another issue I’m having that is not addressed in the article is the identification of the fossils found. The paleontologists found three 500,000 year old teeth – three! Apparently this is enough to say what species they belong to. That alone is amazing to me but I must say questionable too. The anthropologist behind the find, Sally McBrearty, says that the lack of chimpanzee fossils is a “frustrating puzzle” but easily explainable – fossils are rare and the supposed habitat of these chimpanids is not conducive to fossilizing bones. A nice tidy answer to the big problem in the evidential value of the  fossil record but that is for another blog entry.

Nonetheless, it is a fascinating discovery that seemed to have gotten swept under the rug (well I hadn’t heard of this discovery before). McBrearty says in the article that she will return to the area of the discovery to look for more chimpanzee fossils. No one was expecting to find chimpanzee fossils in the hominid habitat but now there is new perspective. Hopefully with these fresh eyes more will turn up – perhaps a couple of phalanges or some rib bones.

--Elise Edoka



1 comment:

  1. It's funny how scientist can find so few fossils and base an entire theory on those few findings! Nevertheless, it's an interesting finding that causes us to question the knowledge that was previously accepted by many. I'm all for it!
    -Rachael Morris

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