…and this is a 
What a day to be stuck in airplanes for hours on end; I had to slurp in a bunch of files on my iPhone and then look at them on that itty-bitty screen, just to catch up on the story of Ardipithecus. Fortunately, you can just read Carl Zimmer's excellent summary to find out what's cool about it.
For a summary of a summary: it's another transitional fossil in our lineage. Ardipithecus ramidus is old, 4.4 million years or so — so it's well before Lucy and the australopithecines. The latest result is a thorough analysis of a large number of collected specimens that shows it is an interesting mosaic of traits: it was bipedal, but not quite so well adapted to terrestrial locomotion as we are, and it had feet with an opposable big toe. And of course it had a small brain, only a little larger than a chimpanzee's.
Digital representations of the Ar. ramidus cranium and mandible. (A to D) The ARA-VP-6/500 and downscaled ARA-VP-1/500 composite reconstruction in inferior, superior, lateral, and anterior views (in Frankfurt horizontal orientation). (E) Individual pieces of the digital reconstruction in different colors. Note the steep clivus plane intersecting the cranial vault on the frontal squama (as in Sts 5 and not apes). (F and G) Lateral and superior views of the ARA-VP-1/401 mandible (cast). (H and I) Lateral and superior views of the ARA-VP-6/500 left mandibular corpus with dentition.
Ardipithecus is clearly different from (but related!) to us, and it's also very different from a chimpanzee. One thing I'm finding baffling in all the commentary is the argument that this somehow shows that the last common ancestor of humans and chimpanzees would have been very unchimpanzee-like, and perhaps closer in morphology to us than to modern chimps. I'm not buying it. Has anybody actually ever suggested that chimpanzees have been in a state of relative stasis for 6 million years? Chimps have evolved in parallel with us for all of that time, so that argument is addressing a non-controversy, or at least, an argument that should have been recognized as silly all along.
We're also going to have to push the fossil record back another couple of million years to get to that last common ancestor, and there's no reason to presume that Ardi's ancestors weren't also rather different from Ardi. We also need to know more about the breadth of the primate family tree at that time; was Ardi a weirdly specialized sub-branch, or actually representative of a wider trend in the ape species that would lead to us? I think this image is a nice way to illustrate Ardipithecus's place in the family tree.
Evolution of hominids and African apes since the gorilla/chimp+human (GLCA) and chimp/human (CLCA) last common ancestors. Pedestals on the left show separate lineages leading to the extant apes (gorilla, and chimp and bonobo); text indicates key differences among adaptive plateaus occupied by the three hominid genera.
Don't get me wrong: Ardipithecus is a magnificent addition to our family album, and the author's of the multiple papers that have come out have done a very impressive job of analysis and documentation. We can all jump up and down with joy at these new data, and we can rightly point to this species and say, "Transitional form! Boo-ya, creationists!"
Unfortunately, I'm also seeing the press mangling the story already. National Geographic says, Oldest "Human" Skeleton Found—Disproves "Missing Link", which is annoying. The article itself isn't bad, but can we just kill the "missing link" nonsense altogether? It's as if the only way some science journalists can grasp a new discovery is by relating it to a misbegotten misconception.
The prize for the very worst coverage has to go to Metro News and the Torstar News Service (is that from the Toronto Star?). They put up an article titled New theory may answer missing link question, which opens with the bizarre assertion, Man didn't descend from apes. There is no new theory here. There is new evidence and further data documenting the details of one lineage's descent. And if you put the phrase "missing link" in your headline any more, we're going to have to put a silly hat on your editors and make them sit in a corner.
But the very worst part is this misinterpretation of the suggestion that the LCA of humans and chimps would have had characters we consider human-like. I guarantee you that this will be the core of the creationist response to Ardi in the near future.
The four-foot, 110-pound female's skeleton and physiological characteristics bear a closer resemblance to modern-day humans than to contemporary apes, meaning they evolved from humanlike creatures -- not the other way around.
Brace yourself, gang. The creationists are going to be claiming that this shows humans were created first, and all of these other hairy beasts the paleontologists are digging up are just degenerate spawn of the Fall.
Life Science
Comments
Posted by: Glen Davidson
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October 2, 2009 11:22 AM
One trouble is that the media often don't understand science much better than the public, so if something shows up that changes the story (always expected, often hoped for, by paleo-anthropologists), they think that it must be threatening to science.
Sorry, no, it's the progress of science that's going on.
Luskin's whining that it was "crushed nearly to smithereens," as if that's unusual for fossils--or necessarily an impediment to the conclusions reached.
Throwing doubts at good science is their single ability, however. Doing science, not so much.
Glen D
http://tinyurl.com/mxaa3p
Posted by: Zeno
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October 2, 2009 11:26 AM
The estimable David Perlman had a nice article on the front page of the San Francisco Chronicle. I'll bet they get two kinds of protests:
(1) The artist's rendering of "Ardi" shows her breasts. Naked titties on the front page of the newspaper. Oh, my!
(2) The article talks about the painstaking reconstruction of the damaged fossil remains. Creationists will promptly chime in with "Aha! They assembled it according to their preconceived notions!" Creationists are quick to accuse others of preconceived notions, but they're a little unaware of how amusing that is.
I'll watch to see if I'm right the next few days.
Posted by: AJ Milne OM
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October 2, 2009 11:34 AM
Ignoring, for a moment, the inevitable obfuscatory asshattery of the creonuts, that's one beautiful, beautiful fossil, and a beautiful piece of work on the part of the researchers.
Slow-cooked science for the win.
Posted by: bobxxxx
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October 2, 2009 11:34 AM
Magical creation asshole and stupid piece of shit Luskin didn't waste any time lying about it.
http://www.evolutionnews.org/2009/10/key_bones_of_new_hominid_fossi.html Posted by Casey Luskin on October 1, 2009 3:41 PM
I think the Dishonesty Institute retards, and other retards like Ken Ham, are no different from Muslim terrorists and they should be treated like terrorists.
Posted by: Ray Moscow
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October 2, 2009 11:39 AM
The devastating Christian response has already begun: http://www.rr-bb.com/showthread.php?t=110943
(from a link posted at WEIT on the same topic)
Time to hang up the "science" and dust off the Bibles, folks. Jebus wins again.
Posted by: Sili
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October 2, 2009 11:41 AM
I see that stridency is an ancient trait. Must be why it's so maligned.
What a refreshing change of pace.Posted by: Roameo
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October 2, 2009 11:41 AM
You know what, I really hope they do adopt that line of argument. If try to say that humans came first, and that these other species evolved from us, regardless of the chronological fuckups they're going to have to use evolution to back that up. And once they start doing that, we've won.
Posted by: Nerd of Redhead, OM
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October 2, 2009 11:46 AM
Josh first posted about this on the Horror thread yesterday, and it was all over the Discovery News (the TV channel) web site yesterday. Very interesting reading. Makes a beautiful fit into the fossil record.
Posted by: Knockgoats
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October 2, 2009 11:54 AM
One thing I'm finding baffling in all the commentary is the argument that this somehow shows that the last common ancestor of humans and chimpanzees would have been very unchimpanzee-like, and perhaps closer in morphology to us than to modern chimps. I'm not buying it. Has anybody actually ever suggested that chimpanzees have been in a state of relative stasis for 6 million years? Chimps have evolved in parallel with us for all of that time, so that argument is addressing a non-controversy, or at least, an argument that should have been recognized as silly all along. - PZ
You're not buying what? There's a real controversy, for example, about whether our LCA with chimpanzees was a knuckle-walker - the argument in favour being that gorillas are also knuckle-walkers, but genetic evidence indicates chimpanzees are more closely related to us than to gorillas, so convergent evolution of knuckle-walking would be required if our LCA with chimpanzees was not a knuckle-walker. The authors of these papers claim Ardipithecus shows no knuckle-walking adaptations, and that it is in several respects closer to earlier ape fossils than to chimpanzees or gorillas, suggesting knuckle-walking is a derived condition and did indeed evolve convergently in chimpanzees and gorillas.
Posted by: neon-elf.myopenid.com
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October 2, 2009 12:04 PM
I was just reading about this on Slashdot about half an hour ago and thought it was something that should be mentioned here and you have beaten me to it.
Very interesting stuff.
Posted by: rlrr
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October 2, 2009 12:13 PM
And of course it had a small brain, only a little larger than
a chimpanzee'sGlenn Beck's.Posted by: ArmandTanzarian
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October 2, 2009 12:17 PM
http://www.icr.org/article/not-leg-stand/
Thought I'd drop by to post the response offered by the Institute of Creation Research. It's not a long read, I doubt creotards have the attention span to read anything even as long as the NatGeo article.
Posted by: truthspeaker
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October 2, 2009 12:22 PM
Which is nonsense. Clearly all great apes are descended from Pak breeders. The relatively large amount of diversity in their descendent species was probably the result of an increased mutation rate caused by the radiation from their crashed lander.
Posted by: ausador
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October 2, 2009 12:23 PM
Casey Luskin seems to be cherry-picking/mis-leading for Jebus again, notice how he repeatedly complains about the condition of the fossil when it was found and the time lag in publishing about it. He wants his readers to disbelieve in the discovery based on this, and even uses quotes from the article in Science about the discovery to support his insinuation. Yet he leaves the most important part of the "turn to dust" quote out of his "slander for Jebus" diatribe.
"They were so fragile they would turn to dust at a touch. To save the precious fragments, White and colleagues removed the fossils along with their surrounding rock. Then, in a lab in Addis, the researchers carefully tweaked out the bones from the rocky matrix using a needle under a microscope, proceeding "millimeter by submillimeter," as the team puts it in Science. This process alone took several years."
I still cannot understand why it is seen as correct to lie, mislead, and fabricate evidence in defense of your beliefs when those very beliefs call your behaviour a sin. That these are people of tiny faith and cynical belief is the only conclusion I can reach. They worship a tiny and impotent god who needs their intervention on the mortal plane to survive apparently.
It is a good thing for us that they honestly cannot see the damage they do to their own cause. We would take thousands of years to defeat this nonsense without them, with them it will only take another generation or two. :)
Posted by: Dania
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October 2, 2009 12:23 PM
At UD, the stupidity has begun:
How did this stupid idea originate? How did they go from "didn't evolve from a chimpanzee-like ancestor" to "didn't evolve from apes"? Seriously, how stupid are these people?
Posted by: MorboKat
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October 2, 2009 12:27 PM
http://www.thestar.com/article/704293
That was the front page of the TorontoStar online yesterday. The words "missing link" are used four times.
Posted by: Sven DiMilo
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October 2, 2009 12:43 PM
? [disclaimer: midterms week, so I have not read any of the primary, and little of the secondary, material on this]
Huh? This fossil postdates the chimp/hominid lineage-split, and is solidly part of the homind lineage, yes? How then does it tell us anything about the last common ancestor of modern chimps and humans?
Are they suggesting that modern chimps--and gorillas?--had bipedal ancestors? Because...why? Whatever "primitive" traits Ardipithecus retains could (more plausibly, to me, so far) have been lost, convergently, in both gorillas and chimps.
I'm sure I could answer all these questions for myself, but that won't happen for a few days. I was glad to see PZ voicing some of the same questions I had in learning about this fossil.
Posted by: shaunotd
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October 2, 2009 12:43 PM
The BBC website made a decent job of the story too, and didn't the term 'missing link' at all. How refreshing!
http://news.bbc.co.uk/1/hi/sci/tech/8285180.stm
Posted by: Glen Davidson
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October 2, 2009 12:44 PM
More predictable dreck from Casey Luskin (OMG, intelligence was used in reconstructing Ardi, not religious platitudes)
Glen D
http://tinyurl.com/mxaa3p
Posted by: Aratina Cage
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October 2, 2009 12:45 PM
The SF Chronicle report linked to by Zeno above notes that the small size of Ardi's teeth indicate Ardi was a peaceful creature. So much for the concept of original sin if, like our cousin Ardi, our humanoid ancestors were peace-loving. (Maybe Genesis is a story for those mean-spirited chimps and not humans after all.)
I guess it is a good thing PZ's book has not been completed yet. It gives him the opportunity to be one of the first authors to address this new commotion coming from the ID, YEC, and Rapture-ready camps after it plays out for a few weeks.
Posted by: Brian Switek
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October 2, 2009 1:01 PM
I don't know which is worse; that some folks are calling "Ardi" a missing link or that Wired said she was our "Baby Mama"...
I've posted my own initial thoughts about Ar. ramidus here.
Posted by: Pygmy Loris
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October 2, 2009 1:03 PM
There are fused carpals in the wrists of Homo, Pan, and Gorilla that are consistent with adaptation to knuckle-walking. I'm of the opinion that knuckle-walking is a derived trait of the African Clade and that hominins subsequently lost it when we adopted habitual bipedalism.
Due to the paucity of data regarding the 6-4mya time period of hominid (African apes in general) evolution, I think it's still a bit too early to say whether Ardipithecus is a hominin or not. This Late Miocene/Early Pliocene time period is still littered with the remains of the great bushy ape tree that developed in the Miocene. We just don't have enough comparative material to draw too many phylogenetic conclusions.
Posted by: Sven DiMilo
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October 2, 2009 1:14 PM
ah, OK, a quick look at PZ's Fig. 2 (btw, lose that stray apostrophe just underneath the fig.; it's embarrassing) and I see where I was wrong.
The "primitve" features retained by Ardipithecus are arboreal adaptations. So they've got the LCA for modern chimps and humans as an arboreal specialist, "palmigrade" meaning (I think) they grasped branches as we (and all other tetrapods?)would, palm down. So then knuckle-walking evolved convergently in gorillas and chimps because of their independent move to (semi-)terrestriality. The hominid lineage, in a third independent descent from the canopy, went bipedal instead. Ardipithecus represents a relatively early stage in that process. The LCA of modern chimps and humans was unlike either because it was more arboreal; think orangs or smart giant gibbons.
That's a cool and plausible story, but man, that's nothing like the impression I had from a light skim of the news, including PZ's account (haven't read Zimmer yet). Creationist lies apart, this is looking like another total failure of science journalism in general.
Posted by: raven
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October 2, 2009 1:15 PM
What is odd is that we have IIRC, a series of human line fossils going back now to 4.4 million years BP. There are no chimp or gorilla fossils. The speculation is that they are forest creatures that don't fossilize often for environmental reasons whereas our line is savannah and plains dwellers which do, at least more often.
It would really help if we did have fossils of chimp and gorilla forerunners.
It is to early to say that we are primitive hominins and the living African apes are the derived ones. But one can make a good case that this is what happened. I can hear it now. Fundie chimps are screaming, "I didn't come from no humans."
Posted by: raven
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October 2, 2009 1:18 PM
Sure. And the neighbor's dog will bark again. With about the same informaiton content and significance. They are just dust in the wheels of progress.
Posted by: Miles670
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October 2, 2009 1:21 PM
#5
Are these people serious? I don't understand why the fuck they're happy to just post away slagging off credible science instead of actually trying to learn for themselves just how credible it is. Why did you have to post that?! I was smiling 5 minutes ago DAMNIT.
Lol but thanks anyway, seeing how idiotic some people can be, whilst it makes me a little ashamed, it also makes me proud to be me.
Posted by: Knockgoats
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October 2, 2009 1:26 PM
This fossil postdates the chimp/hominid lineage-split, and is solidly part of the homind lineage, yes? How then does it tell us anything about the last common ancestor of modern chimps and humans? - Sven DiMilo
Because (the authors say) it has characteristics that indicate no knuckle-walking, and a mode of locomotion in trees resembling that of arboreal monkeys and of earlier fossil apes, not that of chimpanzees or gorillas. Now this set of features could have evolved to allow knuckle-walking, then back, but they evidently find this less believable than convergent evolution of knuckle-walking in chimpanzee and gorilla. I'm not taking a view on whether they are right, but surely the general point is clear: if Ardipithecus has traits that differ from chimpanzees and gorillas, but are common to more distant outgroups, the probability is that these existed throughout its evolutionary history back to common ancestors with those groups, and were therefore shared with the LCA of human and chimpanzee (on the assumption it is indeed descended from that taxon).
Are they suggesting that modern chimps--and gorillas?--had bipedal ancestors? Because...why? Whatever "primitive" traits Ardipithecus retains could (more plausibly, to me, so far) have been lost, convergently, in both gorillas and chimps.
No, they are not. They suggest that our LCA with chimpanzees (and that with gorillas) was a
"palmigrade tree climber/clamberer (not suspensory or knuckle-walking)", with a long, flexible lower back, and flexible palm and wrist (these features are unlike those of extant African apes and more like humans). Hominids, chimpanzees and humans all then adapted to a more terrestrial lifestyle, with hominids evolving bipedality (Ardipithecus being a facultative biped, much less efficient at walking or running that later hominids), while the ancestors of gorilla and chimpanzee independently evolved knuckle-walking and suspensory arboreal movement.
Posted by: Peter G.
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October 2, 2009 1:26 PM
You had me worried there for a minute. I thought those images looked like my cousin Ray but I checked and he's okay.
Posted by: Sven DiMilo
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October 2, 2009 1:28 PM
So well OK I still didn't have it quite right (e.g., "palmigrade" seems to mean moving--all fours--above branches as opposed to hanging below them, and Ardipithecus is itself envisioned as only semi-terrestrial).
Read Laelaps and Zimmer for the real deal.
Posted by: Sven DiMilo
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October 2, 2009 1:31 PM
Thanks, Nick. We crossed comments there. Sorry for thinking out loud before homework.
Posted by: the_fishiologist
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October 2, 2009 1:43 PM
The dreck continues at the Wall Street Journal (of all places - aren't their readers supposed to be educated?).
http://online.wsj.com/article/SB125440678661956317.html?mod=WSJ_hpp_MIDDLETopStories#articleTabs%3Dcomments
The article, however, does not mention any "missing link", which is nice, but I'm a little unclear on what they meant when they said that the discovery of these fossils "widens the evolutionary gulf separating humankind from apes and chimpanzees". Are they trying to say that the LCA is further back than we thought? or simply that humans and apes diverged more quickly than they thought? ambiguous. the commentary makes me grind my teeth though.
Posted by: Ray Moscow
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October 2, 2009 1:47 PM
Yes, they're serious. They would be hilarious if they weren't adults with some measure of influence in society. OK, they're funny anyway.I grew up with these people, and I'm glad to be clear of them. But they're still there, leaching off the accomplishments of science and other pursuits of reason while trying to destroy them.
Posted by: Pygmy Loris
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October 2, 2009 2:06 PM
Looking at the Lovejoy et al. article in Science on the forelimbs of Ardipithecus I'm unconvinced that the genus is part of the hominin clade. This is the problem with the Late Miocene/Early Pliocene search. We need a better picture of the evolution of Pan, Gorilla, Pongo and Homo. All three ape genera are adapted to some degree of suspensory locomotion. Homo retains characteristics of the shoulder and elbow that relate to suspensory locomotion. It's going to take a lot of evidence to justify the evolution of these complexes independently in 4 lineages, one of which has no reason to evolve it if they were already bipedal.
So many of the traits exhibited by Ardipithecus are not traits of extant great apes, but more similar to some of the Miocene apes and Old World monkeys. There doesn't appear to be too much in the way of derived hominin characterics or derived hominid characteristics.
Posted by: lordshipmayhem
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October 2, 2009 2:20 PM
FYI, the free daily Metro News and the Toronto Star are both publications of Torstar. And I've never been terribly impressed by the quality of the Star's reporting, so I'm not surprised they published this pseudoscientific "man didn't descend from apes" crap.
Posted by: The Naturalist
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October 2, 2009 2:27 PM
In our evolution, many branches off our ancestorial line died out. So my question is: how do we know that the particular group represented by this fossil evolved into our species?
Posted by: mythusmage
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October 2, 2009 2:36 PM
And it just so happens that quite recently British scientists in Indonesia have reported finding evidence for the orang pendak. A reputed relative of the orang utan.
A couple of caveats here. One, they could have found hair and tissue from an orang utan. Two, it could be a new sub-species of orang utan. If it is a new species of ape it shows that we don't know this world as well as we think we do, and that there is value in exploring the natural world for new life forms.
On the other hand, the claim that the orang pendak is supposed to be very strong because...
...is not necessarily a good one, because rotting logs are really not all that strong.
Posted by: stptrck75
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October 2, 2009 2:42 PM
..."Degenerate spawn of the Fall" - great movie title
Maybe we could get Kirk Cameron? Fingers crossed...
Posted by: amphiox
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October 2, 2009 2:49 PM
#24: "There are no chimp or gorilla fossils"
Another contributing factor to this may well be the tendency to play up virtually every fossil discovery between 7 and 4 million years ago as being a potential new human ancestor. I recall the discoveries of Orrorin and Sahelanthropus, where the discoverers of each are convinced that their fossil is a human ancestor, and are arguing that the other guy's fossil is on the chimp side of the split. Quite possibly one or both of these will actually turn out to be on the chimp side, and we may well have chimpanzee precursors buried in some museum drawer somewhere, labeled by their discoverers as human ancestors, awaiting reassessment.
#17: "Are they suggesting that modern chimps--and gorillas?--had bipedal ancestors?"
There isn't any evidence that I am aware of to suggest this, but then again the only evidence we have for the hypothesis that bipedal gait was the defining feature of our branch of lineage, arising after we split from the chimps, are fossils from our own lineage after the split, combined with some considerations of parsimony. So if we should one day find an earlier chimpanzee ancestor that turned out to have a bipedal gait, I would only be slightly surprised. And if we one day discover that facultative bipedalism was present in our lineage before the split with gorillas, I would also only be slightly surprised. (One interesting consequence of such finds would arise from the fact that at present we are pretty much defining bipedalism as the characteristic trait distinguishing our lineage from other apes, so if we discover that bipedalism predates the split with chimps and gorillas we would either have to change this definition, or start thinking of chimps and gorillas as human)
Posted by: RBH
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October 2, 2009 3:00 PM
The "Man didn't descend from apes" phrase comes from a press release issued by Kent State, Owen Lovejoy's home institution. The title of the release isMan Did Not Evolve From Apes Says Leading Anthropologist
The PR flack must be angling for an AIG gig.
Posted by: amphiox
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October 2, 2009 3:01 PM
#35: "In our evolution, many branches off our ancestorial line died out. So my question is: how do we know that the particular group represented by this fossil evolved into our species?"
We don't. In all likelihood all the fossils we have represent offshoots and side branches. Even the fossils of early H. sapiens, up to a certain point, are likely not to be directly ancestral to anyone living today. Because the tree is so bushy and fossilization so rare, we are far more likely to find the fossils of cousins than the fossils of direct ancestors. But our ancestors contemporaneous with these fossil cousins will be closely related to those cousins (more closely related, for example, than we ourselves would be to them - your great-great grandfather is more closely related to your great-great granduncle than he would be to you, for example), and thus similar in most respects.
Posted by: Rev. BigDumbChimp
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October 2, 2009 3:23 PM
Posted by: Yubal
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October 2, 2009 3:45 PM
Hey guys!
PZ mentioned something above that made me curious of one thing
How does the chimpanzee family album look like? Since chimps and humans evolved in a similar habitat, or at least close-in-space habitats, and presumably had similar population sizes, we should find fossils tracing the chimpanzee evolution as well. I know these fossils aren't that fancy because they do not show o u r evolution, but I think the evolution of our closest living relative is also highly interesting.
Does anyone know how many fossils in the chimpanzee linage have be found? Which ones they are? Any good scientific literature on that question?
Thanks!
Posted by: Yubal
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October 2, 2009 3:47 PM
...have been found...
Posted by: Strangel
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October 2, 2009 3:55 PM
lol.. nice Rev!
A few weeks ago we had a family reunion for a wedding. Most of them are well educated (quite a few Phd's) and devoutly religious. Every once in a while I would be approached by one of them; "So, I hear you're going for a degree in Paleoanthropology?"
Oh, boy... here we go again. "OK, first off; I need to know how old you believe the earth is." Surprisingly enough (or not) many of these highly intelligent relatives of mine are YECs. After a while I realized there were none whose degrees depended on the truth of our evolution; not even the biochemist. The historian (my father-in-law) is an OEC but offered me no assistance as he watched me dodge around answers which would offend our family and upset the delicate position that the few atheists in the family do hold.
By the second day I just started saying, "Yeah. Crazy, huh?"
Posted by: amphiox
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October 2, 2009 3:55 PM
Yubal #42:
To the best of my knowledge, we actually don't have much significant in the way of fossils for the chimpanzee lineage (ie chimps are the ones who actually have a "missing link"!). I had heard about talk at one time of a hypothesized East/West Africa split, ie the population in East Africa in and around the Rift Valley gave rise to humans, while the West African population went on to become chimpanzees, but I think that's been discarded now due to finding early hominid fossils in West Africa.
As I had mentioned in an earlier post, for fossils dating to very close to the split, it would be hard to tell for certain whether it is on the human or the chimp side, and I think there is likely a bias towards classifying all such fossils as being on the human side (as they'd be more interesting/more likely to attract further grant funding).
A forest environment is also much worse for preserving fossils than a savannah environment (not that a savannah environment is that great for it either), and the human lineage ultimately achieved a much greater geographic distribution than the chimp lineage.
Posted by: amphiox
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October 2, 2009 3:59 PM
re #44:
Of course, there is no correlation between being intelligent and being right. Greater intelligence simply means a greater facility for being mistaken in more complicated ways.
Posted by: Josh
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October 2, 2009 4:21 PM
This isn't true. As written, this statement is really too broad to be meaningful. The "forest environment" can (and usually does) contain multiple sedimentary facies (especialy if we're including soils here...), all of which interact with buried bones differently. If there is a river running through your forest, then that river plays a major role in controlling sedimentation, and overall, your forest should be a rather good place for bones to survive burial. Indeed, all things being equal (which they aren't), most forest environments are probably better at presevation than savannahs just by virtue of the fact that if there is that much vegetation growing there, then there should be more streams (due to more rain) and thus more sediment being moved around and thus a higher potential for burial. If you're talking about soil, then yes, there should be a higher probability of element survival in most savannah soil types than in lots of forest soil types. But, soils isn't the same thing as sediment and saying "forest soils" is not at all the same thing as saying "forest environment." Vertebrate preservation potential tends to be complex, and it appears to be (since not all that much work has really been done in this area), at least in humid environments, controlled more at the facies level (e.g., river channels versus floodplains versus crevasse splays versus levees) then at the "environment" level (e.g., the forested river valley as a whole).
Posted by: raven
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October 2, 2009 4:22 PM
The pictures in the post show a lot of skull details. I read somewhere that a "U" shaped lower jaw is characteristic of fossils on the line to humans whereas a "V" shaped jaw is characteristic of Australopithecines not on the human line.
To my amateur eye, the lower jaw looks more U shaped than V shaped. Anyone who knows more agree or not?
Posted by: bybelknap
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October 2, 2009 4:23 PM
Just popping in to say how much I love this kind of post. It's great; the science, the creotard bashing, the thoughts and ideas banging around - I just learned a new word or two "palmigrade" what a great word! - and the arguments and interpretations and re-interpretations. So many smart people in one place. It is the antidote to the tardensity of UD and AiG, and it smells like Victory!
Posted by: 'Tis Himself, OM
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October 2, 2009 4:30 PM
Pigmy Loris #22
But how do you explain Ken Ham, Ray Comfort, and all the other knuckle-dragging creationist?
Posted by: amphiox
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October 2, 2009 4:36 PM
"But how do you explain Ken Ham, Ray Comfort, and all the other knuckle-dragging creationist?"
Atavisms?
Posted by: NixManes
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October 2, 2009 4:39 PM
This is the perfect event to coincide with 150th anniversary of Darwin's *Origin of Species*! The timing couldn't have been better.
Fundies will be buying blood pressure medication by the pound for the next few months, but that's the price they'll have to pay for sticking with a god delusion that looks increasingly silly with each passing year. They'll scream, yell and quote bible verses for their own twisted comfort, but the rest of us will continue to learn about our history and be glad to have increased the level of knowledge about ourselves.
The party's over here! Come and join us in a toast to the continuing search for knowledge. It's cool to be chasing after knowlege. Really.
Posted by: Yubal
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October 2, 2009 4:39 PM
OK, you guys say there is virtually nothing known about the evolution of the chimp based on fossil findings? Is that maybe because no one is looking for 'em?
Even if the environment is non-favorable for fossilization, there should be at least a few corpses been fossilized over the time of 4-6 millions of years. Let's guess, there might be at least ten bodies down there in the ground, or is that number not realistic?
Posted by: rolanlegargeac
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October 2, 2009 4:41 PM
Test
Posted by: raven
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October 2, 2009 4:50 PM
Hmmm, head injury? Teratogenic mishap? Deleterious mutations?
Maybe there really was an Eden and a Fall and genetic entropy does happen. But it was only for xians. It is their story after all. So the fundie gene pool is running down as they degenerate. But god will show up any minute and Rapture the deserving and kill the rest. And ignore all those pagans and heathens that didn't get in on the ground floor in the Garden, don't believe he exsts, and missed all that great stuff like a worldwide genocidal flood, the Tower of Babel, the jesus Deicide, and 2,000 years of massacres.
This is all in the bible somewhere. Or will be when I have a revelation and found a new cult. The Church of the Fortunate Unfallen.
Posted by: amphiox
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October 2, 2009 5:00 PM
#47:
Good points. One wonders if the paucity of chimpanzee lineage fossils is then simply a matter of bad luck, or an artifact of search methods? Could it be that areas more likely to yield chimp fossils have been missed or avoided by paleontologists thus far? (For example, could it be that the forested areas where chimpanzee ancestors lived and were presumably fossilized are still dense forests today, where it is hard to go looking for fossils?) So much of fossil hunting is dependent not only on what environments were good at preserving fossils in the past, but also on whether or not those environments became, in the present, places where it is feasible to search for and find the fossils.
Posted by: raven
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October 2, 2009 5:01 PM
That might be part of it. Humans are paying the bills and naturally tend to look for human ancestors. Chimps will have to train their own paleontologists.
Regarding forest versus savannah probability of fossilization. That is just something I read in more than one place. Supposedly in forests, a primate dies, falls out of tree onto the forest floor. Which has lots of decomposers and scavengers that promptly dispose of the bodies. The bone scraps are dissolved by typical acidic forest soils.
Whether all this is true or not, I wouldn't know. There might be microhabitats where fossilization will occur. The ancient primate "Ida" that we heard about lately was found in lake sediment. Somehow the monkey fell in, died, and sank to the bottom. But this must be a rare event as there is only one so they made a big deal out of it.
Posted by: Glen Davidson
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October 2, 2009 5:04 PM
Chimp fossils have been found:
http://www.msnbc.msn.com/id/9145721/ns/technology_and_science-science/
Granted, they're on the young side, and just teeth.
I think that as far as environments go, the point re hominin fossils is that volcanic environments are pretty good places in which to be preserved. True, hominins have been found in South Africa in reasonable quantities--I'm not sure what conditions are favorable there. The fact that rift valley fossils are more datable (volcanic ash being the main reason) is certainly part of why the latter are more often sought after.
However, I believe that tropical forests are considered not to be very good environments for fossilization on the whole (of course there could be exceptions), having partly to do with acids eating up the bones and teeth. Temperate forests may in most cases be fine, I don't know.
Glen D
http://tinyurl.com/mxaa3p
Posted by: palaeodave
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October 2, 2009 5:12 PM
To raven (#57)
Not that rare:
http://en.wikipedia.org/wiki/Messel_pit
When I was there with a group a few years ago we found more than a dozen complete fish, a complete bird, a partial bird and a complete turtle, in one afternoon. It was a great day!
Posted by: Glen Davidson
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October 2, 2009 5:14 PM
Or, actually, the rift valley's preservation abilities might be more to do with the rifting than the volcanism, as in that it allows for many areas where sediments accumulate, such as in the Olduvai Gorge.
Vulcanism probably helps somewhat, but as far as I know there aren't many really deep ash falls.
Glen D
http://tinyurl.com/mxaa3p
Posted by: verreauxi
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October 2, 2009 5:16 PM
The chimp fossil record is quite pathetic and the only fossil that I can recall off the top of my head is a canine found by Sally McBrearty.
Folks have argued, on grounds of morphology, behavior, and heterochrony, that common chimps are a better behavioral model for the last common ancestor of humans/chimps than bonobos. This argument is found in a paper called "African apes as time machines" by Richard Wrangham and David Pilbeam.
This argument was also discussed in Wrangham's book Demonic Males. It kinda runs like this (I'm reaching way back into my mind to jumpstart some rather otiose synapses to recollect this): 1) we know humans are unique; 2) that said, we share a lot of behavioral traits with common chimps (group hunting, lethal-raiding, male dominance over females, violence, etc.) and these are not found in bonobos; 3) but what about bonobos, we share traits with them too? which leads to an answer: 4) but bonobos are derived and much of their behaviors can be explained through neoteny and their similarities to humans are likely parallelisms, not homologies, hence common chimps are a better model for the LCA, not bonobos.
To some, though I don't think Wrangham/Pilbeam would argue this, it would imply that common chimps have changed little since about 6-7mya, while both humans and bonobos have changed a lot (since we know that humans have accrued a lot of unique traits--autapomorphies--and because of neoteny, it's likely that bonobos have as well), but since we don't know much about chimp evolution in general (except that bonobos are likely a derived side branch) and common chimp evolution in particular (no fossil record), we might assume that common chimps have changed little from the CA. I think this might explain some of the reasoning behind the "more chimplike" "not chimplike" quotes from folks in the press releases.
Posted by: eddie
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October 2, 2009 5:23 PM
I think the difficulty here in classifying this fossil as closer to human tha chimp, or otherwise, is with the notion that a lineage can evolve a particular trait and later unevolve it. The knuckle thing is a prim(at)e example. If the prevailing environment at one time favours climbing or walking then some taits will be favoured over others. Seem that a lot of previously classified fossils may be misclassified by those thinking that more human = progress.
Also, to be fair to the journos, the phrase "man didn't descent from apes" is technically correct. We both come from some common ancestor. It's just that the sub-editors don't think enough of their readers to bother with details.
Finally, this find does seem to separate humans more widely from other primates. There used to be one gap and now there's two ;-)
Posted by: Josh
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October 2, 2009 5:29 PM
It could be a search image thing (and absolutely yes to the rest of your comment--the modern environment absolutely plays a huge part in how much a given fossiliferous unit is actually prospected--the richest trilobite horizon in the world isn't going to get pawed over all that often if the only outcrops of it are in the middle of the Amazon Basin).
It could also be preservational if we're talking about soils*. If the carcass is sitting on the forest floor for a while, then the probability of it being preserved drops way off (we will likely end up with little bone pieces that get brought deep enough into the regolith so as not to be destroyed by chemical or biological processes).
*Which is why I wrote what I wrote before. Blanket statements like "such and such forest types are poor environments for preservation" don't mean much because forests are not single depositional environments**. The Amazon rainforest: terrible preservation potential if we're talking about the soils of the forest floor. The Amazon rainforest: great preservation potential if we're talking about the levees of the river itself. I reiterate this here only because my last comment doesn't look that clear to me now as I re-read it.
**And of course because the science of modern taphonomy is still so infant--much of the work necessary to back up such statements simply hasn't been done yet.
Posted by: eddie
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October 2, 2009 5:35 PM
And again, this fossil's a girl!
Posted by: Josh
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October 2, 2009 5:37 PM
Spot on.
Posted by: Insightful Ape
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October 2, 2009 6:07 PM
OK this is what I think.
In "The Ancestors Tale" Dawkins goes over the possibilty (albeit unlikely) that the LCA of man and chimp may have been bipedal. The basis for this conjecture is the fossil
known as S Tchadensis, aka "Toumai". Unfortunately only its skull has been found-but still it likely was bipedal given the position of the foramen magnum. Toumai also happens to be about 6 million years old which puts him/her right at the chronological spot where the LCA ought to have been based on the molecular evidence.
So could there have been a line of descent from Toumai, to Luci, to us? I think that is a tantalizing possibilty. If true that would mean that knuckle walking in gorillas and chimps was convergent evolution, as the authors here have concluded.
Posted by: Dania
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October 2, 2009 6:13 PM
How so? Humans are apes that descended from apes and share a recent common ancestor with the other extant apes. Saying that humans didn't descend from apes implies that there are no apes in the human lineage, which is false.
Posted by: Sven DiMilo
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October 2, 2009 6:31 PM
Dania's right, and the same goes for "monkeys."
Posted by: Eidolon
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October 2, 2009 7:08 PM
All the above great discussion does raise the question in my mind as to why there seem to be so few chimp fossils. While there are no chimp paleoanthropologists, humans seem to be interested in just about every other fossil. Is it just a population size thing with chimps being less numerous? Thanks to all who have added to the discussion.
BTW stptrck75 @37
Degenerate Spawn...great band name.
Posted by: Pew Pew Lasers!
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October 2, 2009 7:08 PM
In response to number 5. That forum made laugh so hard, especially when I read this.
"Don't start from the proposition that everything you learned in science class was correct, and then try to make God fit into that picture. Instead, start from the position that everything in the bible is true, and then try to see how science fits in with that. If it doesn't fit, it's the current world's view that's wrong, not the bible."
Posted by: Susan
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October 2, 2009 8:00 PM
Waiting for PZ to speak at AAI and it's standing room only!
Posted by: amphiox
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October 2, 2009 8:01 PM
It may be possible to settle the question as to whether or not knuckle walking in chimps and gorillas is convergent or not, but carefully analyzing the anatomy and behavior (and if possible, molecular biology) associated with it in both species. If they are convergent we should expect to see key differences that would attest to this fact, since convergent evolution tends to produce similar, but not identical features.
And if they were not convergent, but homologous, then any observed differences should fit into a pattern consistent with common descent.
Posted by: godlesschick
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October 2, 2009 8:19 PM
I'm pretty sure I've yet to see this mentioned, but on NatGeo's site there's a little more info regarding bipedalism and it's inception. It's been around awhile but I hadn't heard of it til now. From the site:
"Divergent big toes are associated with grasping, and this has one of the most divergent big toes you can imagine," Jungers said. "Why would an animal fully adapted to support its weight on its forelimbs in the trees elect to walk bipedally on the ground?"
One provocative answer to that question—originally proposed by Lovejoy in the early 1980s and refined now in light of the Ardipithecus discoveries—attributes the origin of bipedality to another trademark of humankind: monogamous sex."
It goes on to explain more about it, but I just find that incredibly believable... not to mention it was supposedly the males who started this - all for some sex!
link: http://news.nationalgeographic.com/news/2009/10/091001-oldest-human-skeleton-ardi-missing-link-chimps-ardipithecus-ramidus.html
Posted by: Darren Garrison
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October 2, 2009 8:24 PM
Poll alert!
"Creationism" is getting way too much of the vote (33%).
Do your thing.
Posted by: Darren Garrison
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October 2, 2009 8:29 PM
Dammit:
http://www.tmz.com/2009/09/22/kirk-cameron-plays-the-hitler-card/
Posted by: Cuttlefish, OM, CR
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October 2, 2009 8:35 PM
It’s predictable as sunrise; it’s predicable as tide;
As the evidence is published, it is just as soon denied.
“It’s the fossil of a monkey!” “Hey, my brother’s also short!”
“There is nothing in the Bible that’s denied by this report!”
“Evolutionist conspiracy!” I cannot list them all,
As if Ardi acts as proof there was Creation, and then Fall.
There will never be a fossil found to calm the silly storm,
That’s accepted as example that’s transitional in form.
The specimens were numerous, but never quite enough—
Unless you’ve found “the missing link”, they’re gonna call your bluff.
Our family tree has changed again, as many times before;
Each fossil was disputed in its turn, so what’s one more?
How comforting—there’s one thing that’s consistent from the start:
Creationists and ignorance will never, ever part.
http://digitalcuttlefish.blogspot.com/2009/10/ardi-you-gorgeous-creature.html
Posted by: Kirian
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October 2, 2009 9:07 PM
Breaking news! PZ Myers changes stance on evolution!
I had to go after the obvious quote-mine... sorry for the cheap shot. This is a truly awesome find, and therefore it's no surprise the creo-bots are already out there braying about it.
Posted by: MikeS29
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October 2, 2009 10:08 PM
Cuttlefish, you gorgeous creature, you!
Posted by: Sven DiMilo
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October 2, 2009 10:31 PM
Cuttlefish, can you sing?
You should have a song-writing partner.
Posted by: Jorge
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October 3, 2009 1:09 AM
I was reading this blog while waiting on my trophy wife at a Physician's appt - inside the local Catholic Hospital - through the Hospital Guest User Internet Filters - (won't do USENET though.) No Pron, A bit on the slow side, but it's free. Now if I can just find an outlet around here......
At least this Catholic Hospital has the good sense NOT to filter PZ's blog pages. There are quite a number of other places that won't come up though. ;-)
Posted by: monado
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October 3, 2009 1:19 AM
As I understand it, the chimps and gorillas bring different wrist bones into play when knuckle-walking; thus it is plausible that the habit evolved separately in each.
Brachiating occurred earlier in the family tree and is responsible for the wide, flat chests of hominins.
Posted by: Sonya
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October 3, 2009 1:42 AM
Jorge - I hope your wife feels better very soon. Be sure to take good care of her and give her lots of extra attention. Telling her how much you care is guaranteed to make her feel better!
Posted by: Jorge
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October 3, 2009 2:41 AM
#82 Sonya, Thank you very much for your kind words. My beautiful and sensitive Trophy Wife has had a rough time, and deserves some extra attention. She hasn't been able to drive for the last year, so I do the chauffeuring. I have found quite a number of places that have WiFi for customers as I wait in different places for different appts. While the Local Catholic Hospital System has a heavy filter rate, it does allow some freedom of thought to leak through.
Posted by: Drosera
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October 3, 2009 5:54 AM
That seems to be the position of Dr. Lovejoy himself. See:
http://www.kent.edu/news/newsdetail.cfm?customel_dataPageID_9299=27947
(link supplied by Michael Heath)
To me it's largely empty semantics. And we can still say that man descended from monkeys.
Posted by: Jeff Eyges
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October 3, 2009 12:08 PM
@#5: The devastating Christian response has already begun
One of the comments at Rapture Ready:
the other thing is that they need....absolutely need...to believe this mess. Otherwise their self directed view of life don't work.
They should just change the name of the religion from Christianity to Projectionism and get it over with.
Posted by: eddie
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October 3, 2009 12:12 PM
Dania @67; I totally agree. That important qualifying words like 'extant' are left out by editors that don't respect their readers was the point I was making.
Posted by: Jeff Eyges
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October 3, 2009 12:20 PM
Oh, good grief! Here's another gem from that thread:
Not long ago I listened to a lecture by Chuck Missler in which he proved something you never hear of in the MSM or really in modern science teachings....they can't, it has too many Creation implications.
They have now proven that time is slowing down....literally. And at a measurable and predictable rate. It was first proven over 50 years ago by a Christian and he was laughed almost out of the academic world. Now, since they have gone to the Cesium Wold Clock, any number of people have proven it.
And....if you take the rate of slow down back to historic and beyond times....guess how old the world is?
Ya guessed it! If this is true, science and Creation are, again, not at odds. It makes all the sense in the world considering the Law of Thermodynamics (forget, 1st or 2nd law...order to disorder)
to which another genius replied:
That i havent heard about yet...but i have heard chuck talk about an australian physicist that believes the speed of light was slowing down. He stated that originally the speed of light was the same as the speed of gravity but has slowed to its current speed.
I've gotten yelled at for saying this, both here and at Ed Brayton's, but they shouldn't be allowed to vote. We need mandatory testing of intelligence and sanity as a prerequisite.
Posted by: Lynna, OM
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October 3, 2009 12:30 PM
Those males, they'll do anything for sex.Posted by: Drosera
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October 3, 2009 12:54 PM
eddie @86,
Don't shoot the messenger. Here are quotes from Dr. Lovejoy, one of the co-authors of the Ardipithecus publications, as cited on the website of his own Kent State University:
He says 'apes,' not 'extant apes,' which is consistent with his saying that "apes in many ways evolved from us." In other words, the LCA of chimps and humans should not be called an ape, according to Dr. Lovejoy. So, stop bashing journalists over this, it's not fair.
Posted by: Ichthyic
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October 3, 2009 5:20 PM
So, stop bashing journalists over this, it's not fair.
you might want to capitalize "this", or bold it, or something to highlight the fact that journalists are still ripe for critcism wrt science reporting.
moreover, it's obvious that this is most assuredly a case of "broken clock" syndrome; it's not like the journalists knew wtf he really meant.
Posted by: Ichthyic
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October 3, 2009 5:22 PM
Those males, they'll do anything for sex.
indeed...
http://www.youtube.com/watch?v=y8skJxMwWSs&feature=player_embedded
Posted by: Ichthyic
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October 3, 2009 5:26 PM
They should just change the name of the religion from Christianity to Projectionism and get it over with.
concur!
seconded!
Posted by: Dania
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October 3, 2009 5:52 PM
So, Dr. Lovejoy is using a definition of "ape" that doesn't include humans nor any species in the human lineage. If that's how he, journalists and creationists are using the term, then the phrase "man didn't evolve from apes" is obviously correct. I just can't find a good reason to use the word that way, and I think it's misleading.
Posted by: Drosera
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October 3, 2009 6:34 PM
Ichtyic,
In this case I can't blame the journalists, seeing that even PZ didn't know what Lovejoy really meant. We have already seen in the case of Ida that scientists themselves are not always above creating a hype; maybe something similar is happening here ('the missing link was not an ape after all').
Dania,
I agree that it is confusing, if not misleading, but what I think Lovejoy is saying is that in his view the term 'ape' refers to a grade, not to a clade.
Posted by: Drosera
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October 3, 2009 6:36 PM
Sorry, that should have been Ichthyic.
Posted by: Sven DiMilo
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October 3, 2009 6:57 PM
Yeah, but wtf? Is it a "grade" that includes orangutans? Then we had apes in our ancestry. Lovejoy isn't making sense, unless he excludes from "apes" an animal different from both extant chimps and humans but ancestral to both...which doesn't make sense.
Posted by: Drosera
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October 3, 2009 7:16 PM
I didn't say that it made sense to me. Lovejoy will have to concede that at some point in our phylogeny one of our ancestors was not human.
Posted by: Dania
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October 3, 2009 7:28 PM
I think you're spot on. This is probably another example of a scientist trying to make his finding sound as revolutionary as possible. It's totally unnecessary, though. This fossil is interesting in its own right.
Posted by: DingoJack
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October 4, 2009 11:56 AM
What a fascinating and awesome story. I learnt a new word too! "autapomorphies" (just for dummies like me & anyone else who is afraid to ask).
Plus, a got to witness a Kakapo try and shag a cameramen (gives a whole new meaning to 'the camera loves him'). How cool is this!! - DJ
Posted by: monado
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October 4, 2009 1:32 PM
I wonder if Prof. Lovejoy was simply saying that we can't look at the other modern great apes and imagine that the ancestor of us all was not just like one of them (because they've been evolving all along, too). Ardipithecus being semi-bipedal and semi-arboreal shows that chimpanzees evolved to be more arboreal.
Please don't jump to the conclusion that he's being misleading or hyping his discovery. It's more likely that he knows what he means when he thinks of "apes" and so did not feel any need to qualify it with "extant" or "modern African."
It will be fascinating if we can push back the story of human evolution and find out how we got from brachiating to clambering. Or is that already known in the monkey part of the story? Our anti-monkey prejudices keep "the story of human evolution" from firmly grounding itself in the monkey clades, at least in popular narrative. They all seem to start with hominids.
Posted by: Drosera
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October 4, 2009 5:17 PM
monado,
No expert would have claimed that CLCA would look exactly like a chimp.
Not necessarily. The CLCA could still have been quadrupedal and arboreal.
Of course Dr. Lovejoy knows that. Nobody doubts his expertise. But he should also know that most people mean something else when they refer to 'apes', and he should know that it is at least confusing to say: "People often think we evolved from apes, but no, apes in many ways evolved from us." This can only be true if you imply that gorillas and orangutans are not apes, and if you further assume that we are descended from Ardipithecus, that CLCA resembled Ardipithecus, and that CLCA is more like a human than like an ape. These are all hypotheses. I have little doubt that if Ardipithecus would be alive today it would be put in a zoo rather than in a hotel.
Posted by: Cuttlefish, OM, CR
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October 4, 2009 6:18 PM
The truth is, though it makes me sad, Where would we put it? A GEICO ad.Posted by: PaoloV | October 20, 2009 3:34 AM
I agree completely with killing the "missing link" comments - I've mentioned the pointlessness of the term a couple of times before and I think that we would all benefit from presenting a united front in denouncing it's use when making comments on online articles. One day the journos might take note.