Science to publish Ardipithecus ramidus paper

That's what Kambiz Kamrani is saying. Significance:

Owen Lovejoy is one of the authors of the paper, and he says that the fossil changes the notion that humans and chimps, our closest genetic cousins, both trace their lineage to a creature that was more like today's chimp and we'll have to be rewriting our text books soon. This is big folks. What this means is that our common ancestor was a bipedal forest forager and that chimps were an evolutionary offshoot.

Update: John Hawks & Carl Zimmer.

Update II: Science's Ardipithecus page is up. You can get the papers free with registration.

More like this

I'm still waiting on the release of the papers, but if Ar. ramidus has bipedal adaptations but not knuckle-walking ones it would be consistent with the hypothesis that walking bipedally is an exaptation in hominins. This has been kicked around for a few years and supported by biomechanical studies, so it would be cool to have some fossils throw some support to that hypothesis. It isn't a novel idea, but it definitely grates against the "classic" image of a knuckle-walking, chimp-like human ancestor.

That quote seems a bit overblown to me, for a couple of reasons. One is that, even if the ancestor isn't exactly chimp-like, it's still more chimp-like than human-like in most respects. That it isn't exactly chimp-like, and that it has a few things more in common with humans, should never have been a surprise. To think otherwise would be human chauvinism.

The other reason is that, since Ardipithecus ramidus is a stem-human, it can't tell us what the polarity on these characters was. Maybe chimpanzees developed knuckle-walking on their own, but maybe knuckle-walking was lost by stem-humans very early on. We need a member of the human-chimpanzee stem group before we can determine this, and right now all we have are partial specimens like Sahelanthropus tchadensis and Orrorin tugenensis (unless those are, as some say, stem-humans, in which case we have nothing).

Well, I guess I'll wait for the paper to come out later today....

It's interesting, but I've already seen claims in the media that this means that "apes evolved from humans" rather than the other way around. Stoked in part by some scientists.

""People often think we evolved from apes, but no, apes in many ways evolved from us," Lovejoy said."

'Study: Man did not evolve from apes'
http://www.upi.com/Science_News/2009/10/01/Study-Man-did-not-evolve-fro…

I know what Lovejoy means but he ought to shut up before further confusing the unwashed lay public who don't know jack squat about cladistics, locomotory morphology, or mosaic evolution.

Ardipithecus was, of course, a dumb, poop-chucking ape that we would put in a zoo without hesitation, just like the more primitive Morotopithecus. Morotopithecus was claimed by Aaron Filler to be a bipedal "humanian" primate. Oh, brother.

Yes, despite what Lovejoy and Filler say humans did in fact evolve from apes, whether or not Ardipithecus or Morotopithecus were direct ancestors, how bipedal they were, or how much time they spent on the ground.

So they're bipedal when they're on the ground rather than in the trees where they spent most of their time. Well, so are gibbons. Put a suit on a gibbon and it kind of looks like a little person. They're still apes.

Hey Brian (Laelaps), why do you say bipedalism is an "exaptation" and not an adaptation? I'm not trying to be confrontational here (i.e., I don't have a alternative view in mind), I'm just wondering what you meant?

Errrr... I thought we were apes, so why do they say we evolved from ourselves?