Ardipithecus ramidus

Exciting!

I appreciate all this material being gathered in the one spot.

Note that you can download PDFs of all the journal articles on Ardipithecus ramidus for free at that link if you register.

The only downside is they ask a bunch of personal info in the registration process.

Also note that one of the segments doesn't have a link to the PDF. That was an error. The PDF is there -- they just forgot to link it.

I was able to create the link by hand:

http://www.sciencemag.org/cgi/reprint/326/5949/40.pdf

(That link will only work if you have registered and are signed into the website.)

The official documentary on the Ardipithecus finds will debut tonight on the Discovery Channel.

I believe they created it in close consultation with the scientists who published the recent journal articles, so the documentary should be reasonably accurate.

This is fascinatin' stuff.

However, this:



--is an example of the problems that arise when journalists describe science. If, as the linked article claims, the last common ancestor between the genus homo and the great apes was six million years ago, then one and half million years later does not qualify as "soon after," and there is not necessarily a plausible basis for assuming that ardipithecus is the link from that common ancestor to the Australopithecines. It is entirely possible that there is yet another intermediate species, or even more than one--both before and after ardipithecus. This is not a big deal, but i do wish people who are essentially journalists would not make statements which are essentially scientific in character.

And i've learned that these scientists are not suggesting that ardipithecus is necessarily the only transitional form from the common ancestor to hominids.

I took the little dogs for a sashay this evening, and when i walked back in the door and turned on the teevee, i punched in the programming guide. Coincidentally, the channel selected on the receiver was right next to the Discovery Channel, so i saw "Ardi" in the programming guide, and immediately selected it. I had missed maybe two minutes of the program. I had forgotten all about it, too, so discovering this was serendipity.

Lots of surprises, not the least of which was the high quality of the program itself. I'm pretty disillusioned with contemporary programs, but they did a first rate job on this one.

First, they detailed the seventeen year process whereby the bones were found, assembled and studied to produce the results we can now peruse. That was the first part. The next part looked at the implications of the skeletal structures they found. Ardipithecus had a cuneiform bone (i.e., wedge-shaped) in the wrist characteristic of "knuckle-walkers," but, the rest of the bones of the wrist and hand were not the bones of a knuckle-walker. Furthermore, the pelvis clearly shows that ardipithecus was bipedal.

They then briefly reviewed the geological data which placed the remains very precisely within a 100,000 year time period based on the argon content of volcanic glass. They are able to date the remains from the stratum to 4.4 million y.a. plus or minus 50,000 years--which is pretty precise for this kind of thing.

The next part was a look at the environment from which ardipithecus arose, and contrary to long-held assumptions, it was not a savanna. The conventional wisdom ran that bipedalism would have been selected for in a savanna environment, when there were few trees. But the study of the environment, based on other fossil bones and the fossilized remains of plants show that in that time period, the area was forested. And ardipithecus had prehensile toes, with a very nearly opposed big toe--so you have a bipedal creature which retained the structure of feet useful for climbing.

They went over the methods with which the bones were studied, including microscopic CAT scan technique done in Japan. They also did a detailed account of the artist who reconstructed the image of ardipithecus, along with their use of a Hollywood company which does motion studies of how the musculoskeletal system articulates. They got a very small stunt woman of Asian descent who is the same size as the woman whose remains were found, and did computer-assisted studies of her walking and climbing.

Altogether, a fascinating and extremely well-done program. At the very end, they told of some fossilized bones which they have tentatively dated to 5.7 million y.a. in the same region of Ethiopia. Fascinatin' stuff.

Thanks for the followup, setanta.

You bet, Boss. If you get a chance, check out that program on the Discovery Channel.

No cable service.

Here's a link for the Discovery Channel's web page on this subject. As this program is contemporary, it will probably be a while before you can access it, but i'll bet that at no terribly distant date in the future the program will be available in their video library. It runs two hours with commercials, so i suspect between one and a quarter and one and half hours without commercials--if you have dial-up at home, that could take all day to down load. But it would definitely be worth your while, and if you have DSL, it shouldn't be that much of a problem. Check them out every once in a while to see if the program is in their video library.

At the top of that page there is a link for video, and if you hover your mouse over the rubric, a drop-down menu appears with a "Watch full episodes" link. Check it out from time to time to see if the full program is available. Right now, there are several clips from the program available.