Ergaster

Part two of three
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What made them bipedal is the same kind of anatomy that makes us bipedal. Hip bones that are bowl-shaped, and shortened from top to bottom. This shape shifts the position of the hip, thigh, and abdominal muscles so that the leg can be swung out and around, that the thigh can be extended in front of the body, and so that the torso can be balanced upright over the hips. This is NOT the configuration that is found in apes, who have tall and narrow hip bones, with the important locomotor muscles in a completely different position around the hip joint than in australos and humans.

Lumbar lordosis. the curvature in the lower back found in humans that allows us to stand straight. Australos have lumbar lordosis, apes do not.

Widened sacrum. The sides of the sacrum are very broad and flared in australos and humans, indicating that body weight is concentrated in the sacrum and distributed outward through the sacral alae, through the pelvis, and into the thigh bones. Apes do not distribute their body weight in that manner (it is not concentrated onto the sacrum), so their sacrum is very narrow.

Femoral angle. The condyles (the pair of bumps) at the knee-end of the femur in australos and humans are not at the same angle-that is, if you place both condyles on a flat surface, the shaft of the bone tilts off to the side. This is because when both humans and australos stand upright, the knees come together at the midline of the body. The ape femur has no angle. If you place both condyles on a flat surface, the ape femur sticks straight up in the air.

Patellar groove. Because of the femoral angle, there is a tendency for the kneecap to want to be pulled off to one side. The deep groove on the front of the femur, and the elevated lip along the outside edge of the groove, helps keep the kneecap in place. Apes do not have it, because they do not need it.

The horizontal angle of the distal tibia. In a biped, the articulation between the lower leg and the ankle bones is horizontal, for obvious reasons. In apes, it is not.

The internal stress-reducing structure of the spongy bone of the hip. Radiographs of humans and australos have shown that the arrangement of trabeculae in the hip bones of australos is arranged in largely the same way as it is in humans-a way that disseminates stress and distributes the weight of the body into the thigh bones. This arrangement is absent in chimps and quadrupedal primates, because the body is not habitually held upright (see: Galichon V & Thackeray JF. 1997. CT scans of trabecular bone structures in the ilia of Sts 14 (Australopithecus africanus), Homo sapiens, and Pan paniscus. South African Journal of Science 93:179-180).

These are just some of the anatomical correlates of bipedalism. They are all found in modern humans and in australos. None of them are found in apes.

Australos did not knuckle-walk. There is evidence that the last common ancestor of African apes and australos (and humans) knuckle-walked, but that this was lost in the lineage leading to humans (i.e. in australos and earlier bipedal hominids). Modern human wrists and finger bones do have hints of this knuckle-walking past, but you can tell that australos did not knuckle-walk because there is no evidence that they bore weight on their forearms (their elbow joints and finger joints look pretty much like those of modern humans).

ALL the evidence says that the ONLY way australos walked while on the ground was on two feet. They were not quadrupeds at all.

I hope you start checking your sources rather more carefully. And since no-one expects an australopithecine to behave like a modern human…shrug….

[quote]Deb: There was actually a fair amount of variability in the fossils. A further, greatly enhanced study that included a large number of primates, showed that the link between locomotion and the proportions of the bony labyrinth is even LESS clearcut than was thought, and no direct associations can be made. However, I have seen no creationist source cite this later, more comprehensive paper--could it be because the conclusions are not very favourable to them? This study is: Spoor F. & Zonnefeld F. 1998. Comparative review of the human bony labyrinth. Yearbook of Physical Anthropology 41:211-251.

My point is that creationists have a bad habit of not modifying their arguments in the face of plainly contrary evidence. I predict that this argument will continue to be used even though it has been markedly weakened by subsequent research. At the moment the fact that the bony labyrinth is not like that of modern humans is evidence of nothing, except the entirely trivial observation that australos were not modern humans….well, duh.

HARUN YAHYA???? BWAHAHAHA!!!! That source is even more ridiculous than quoting Duane Gish or Kent Hovind, if such a thing is possible! But go right ahead and use it, if personal credibility means nothing to you….

Since the relationship of australos to humans is not dependent upon the proportions of the inner ear (since it is not dependent upon any single character, anyway), the quote is meaningless from an evidentiary standpoint, as well as a credibility one.

See above, about the nature of the debate. You have completely missed the point. NO debate about the fact of bipedalism. Please learn the difference.

Nope, wrong again. Try reading for comprehension, specifically the part that says "This suggests that HER ANCESTORS…walked on their knuckles". Not "she", but her ANCESTORS. I addressed this above, if you recall. The wrist of Lucy has a remnant of that knuckle-walking past, just as you and I have a remnant (we have lost the one referred to in the article, but we share some others with Lucy that stabilize the wrist). The retention of these wrist-stabilizing features no more means that Lucy knuckle-walked than they mean that we knuckle-walk. In fact, we know she didn't because, as I said above, there are no features in the elbow and fingers that indicate any ability to bear weight on the forearms, features that the knuckle-walking gorilla and chimp most assuredly DO have.

And before you start referring me to websites or other articles, when the original article came out, I went to the lab and compared the fossils for myself. I already have notes and sketches. I already know exactly what everything looks like. This is not evidence that Lucy knuckle-walked, and the articles do not claim it is (there is a longer, more recent article that came out a few months ago).

[quote]"We've got to have some ancestors. We'll pick those. Why? Because we know they have to be there, and these are the best candidates. That's by and large the way it has worked. I am not exaggerating." (Nelson, Gareth [Chairman and Curator of the Department of Herpetology and Ichthyology, American Museum of Natural History, New York], interview, Bethell T., The Wall Street Journal, December 9, 1986, in Johnson P.E., "Darwin on Trial," InterVarsity Press: Downers Grove Ill., Second Edition, 1993, p76)

"Restricting analysis of fossils to specimens satisfying these criteria, patterns of dental development of gracile australopithecines and Homo Habilis remain classified with African apes. Those of Homo erectus and Neanderthals are classified with humans." (Holly Smith, American Journal of Physical Antropology, Vol 94, 1994, pp. 307-325.

Irrelevant, meaningless, and completely out of context (please explain why I should pay any attention at all to a fish and snake expert about human evolution????) What "criteria" is Holly Smith referring to? What is the significance of patterns of dental development to the discussion we are having here, and why do you think they have any? You appear to be grasping at random.

Since we have already established that australos didn't walk like modern humans, and that being identical to modern humans is not a prerequisite to being ancestral to modern humans (in fact, it would probably indicate that they weren't)….what's yer point? Berge certainly believes they were bipedal, and she does not say otherwise in this article (and yes, I do have it in my files…).

Irrelevant. He is not referring to WHETHER australos are bipedal at all. That is one fact that there is no uncertainty about whatsoever. Why don't you fire off an email and ask?

I do say so, and you have utterly failed to demonstrate otherwise. Not a single one of your quotes contradicted the fact of australo bipedalism.

Are you sure you aren't so blinded by your own bias that you are not simply ignoring all that inconvienient evidence that they were bipedal? I mean, not a single solitary one of your quotes actually supported your position, and you CLEARLY lack the expertise required to even know enough not to make brain-dead statements like "how could an ape be like an ape from the waist up…." Duh. Most people who don't know anything at all about a topic have enough humility to try not to completely embarrass themselves in public; what is it about creationists that they so often lack this characteristic? Bait, it is plain as day that you don't know your coccyx from your olecranon process, so you have no idea whatsoever how australos compare to either humans or apes, or even where to begin to know. You have made a LOT of factual errors. As the man once said: if you find yourself in a hole, the best thing to do is stop digging.


I wish you would stop claiming that people "forget" this and that, because nobody has "forgotten" anything. It's simple: your interpretations are wrong. You are relying on unreliable creationist sources, you haven't read the articles that contain the quotes for yourself, you cannot or will not access the original material, and you do not have the necessary knowledge or training to assess what is important or what anything actually means. The skull of a Homo erectus does not look like the skull of a Neanderthal. If you cannot see the difference, it is not because the entire paleoanthropological community is lying to you, is insane, or is deluded en masse by Satan-it is because YOU do not have the personal expertise to know what to look for. Simple. Likewise, there are a large number of skeletal differences between the Nariokotome Homo erectus and modern humans, and Alan Walker himself contributed to and edited a massive monograph that compared and delineated those differences (Walker A. & Leakey R. (eds) 1993. The Nariokotome Homo erectus Skeleton. Cambridge: Harvard University Press), so I must question the context of your quote.

The skull of afarensis is not of that an ape. It differs in crucial ways. I would suggest that you stop trying to demonstrate your anatomical knowledge, because…you have none, and it is painfully obvious.

The innominate is not the "hip joint socket" (that is called the acetabulum). The sacro-iliac articulation was badly damaged during fossilization, but the hip itself (the innominate) fit back together fairly well; whatever distortion was present had no effect on the overall shape and proportion of it-in order to change that, you'd simply have to smash it into powder with a hammer. Ain't possible. Besides, there already exists an almost complete australo hip, one that's been around for decades before Lucy was ever found-Sts 14. The two are consistent in morphology; in fact, they are almost identical (it would be rather strange to have the hip bone of an australo from East Africa and the hip bone of an australo from South Africa get distorted in exactly the same way, don't you think?).

Anyway, I don't have to look at pictures of Lucy, I have handled a cast of the fossil myself, and that includes the hip bone. So I know what it looks like, I know where the damage is and isn't, and it looks far more human than it does any ape. It is not identical to the hip of modern humans, but it is so close that the differences are in the fine details, and it is, of course, unambiguously bipedal. There's no way around it, I'm afraid.

LOL!! Yeah, right! Bait, admit it-you couldn't tell if that knee belonged to your grandmother or to Bonzo the chimp! Let's not play games, here. You don't have the faintest clue how to tell the difference, do you?

"We", Kemo Sabe? Speak for yourself. Take a course in human evolutionary anatomy and then get back to us. I don't have any trouble telling the difference.

For you to support your assertion. You are claiming that there is a debate in the profession about the FACT of australo bipedalism. Need I repeat all this? Every quote you have provided, if they were relevant at all (and many simply weren't-all the blather about what the footprints looked like were quite irrelevant to the issue, because even if humans did make the tracks, that says nothing whatsoever about the bipedality of australos), had to do with the nature of australo bipdalism, not its factuality.

Using another source you have not read, Bait? Let's complete the quote (which comes from the abstract), shall we? It goes on to say: "Discovery of 2.5 Ma hominid cranial and dental remains from the Hata beds of Ethiopia's Middle Awash allows recognition of a new species of Australopithecus. This species is descended from Australopithecus afarensis and is a candidate ancestor for early Homo. Contemporary postcranial remains feature a derived humanlike humeral/femoral ratio and an apelike upper arm-to-lower arm ratio." (p.629)

Shall we finish the authors' train of thought here, as well? You seem to have rather unceremoniously cut them off:

"The 2.5 Ma Bouri Hata hominids bear directly on these issues. (p. 630).

So in other words, instead of reinforcing the problem of a lack of fossil evidence, your quote actually PROVIDES evidence, not only for remains within the time frame in question BUT ALSO a possible ancestor for Homo. Boy, I love irony!!


It would have been better if you had provided accurate quotes, don't you think? But let's look at your "analysis". Firstly, the discovery is not of a "new, similar species to Australo's (sic)". It IS an australopithecine. It is a new species of australopithecine. This is not nit-picking. If you want to have some small credibility, you must demonstrate at least a minor familarity with the most basic terms and concepts. You do not.

Secondly, White (and it would be DR White) was NOT referring to the origin of the species Homo sapiens! PLEASE, if you learn anything at all, learn that when one refers to the genus Homo, we do NOT automatically mean Homo sapiens, and if we talk of the origin of the genus Homo, we DEFINITELY are not referring to H. sapiens. I doubt very much, just judging from the-um, lack of expertise you have so far displayed here, that you could distinguish between the earliest species of Homo and its immediate non-Homo ancestor. If evolution is true, they should look exceedingly similar and may differ in only very small ways. In fact, the article you attempted to quote from discussed this. Did you not read it?

There are some issues over the origin of the species Homo sapiens, but that is an entirely separate discussion from the one here, with a whole other set of researchers. Nothing to do with this discussion.

Sorry, Bait, but you still don't get it. The quotes you have provided are either irrelevant to the question of bipedality, or discuss HOW australos are bipedal. NONE of them question THAT australos are bipedal. I suggest you really try to grasp this fact, and take a careful look at the references.

Irrelevant. We already know without doubt that bipedalism preceded encephalization. Since natural selection clearly did not "eliminate that species", your question is meaningless. In actual fact, the fossil hominid record indicates that bipedality alone was an enormously successful strategy, because there are no less than 8 species of australopithcines that were bipedal, and several of these species lived at the same time. The evidence seems pretty strong that bipedalism was a niche that led to a great diversification of hominids, including the species that was ancestral to Homo. Even if we do not know exactly why hominids became bipdal, it was beyond question an extremely successful adaptation. Your speculations above bear no relation to reality.

It means nothing whatsoever. Johanson's "contentions" have been more than supported by the evidence. If I search my database for articles about A. afarensis, I get dozens of hits. If I add "and Johanson" to the search, I get three. In other words, Johanson has contributed very little to the actual analyses of A. afarensis. It is specious to focus on the contributions of a single individual.

Bait original: Australopithecine members had much longer and curved toes (phalanges) and fingers. They also had a cranially orientated shoulder joint and other features of the arms, typical of tree climbers. As well as the foot, and foramen magnum, we see bipedalism in the shape of the pelvis and the angle between the thighbone and the knee (Leakey, 1994).
Deb: Well, so far so good; are you sure you wanted to include this?

LOL!! And what do you think the arms of bipedal walkers would look like? Last time I looked, bipeds walk with their legs, not their arms!

At any rate, the orientation of the shoulder joint is ho-hum news. Coulda told you that myself.

By the way: compared to all other animals, only humans and the apes have a shoulder joint that allows for complete rotation of the arm while holding it above our heads, along with a broad thorax that places our shoulder blades at the back instead of on the sides. Apes have this enormous flexibility because of their origins in arboreal settings. Now why should we have exactly the same anatomy and flexibility of the thorax and shoulder?

Well, it's not exactly "Johanson's hypothesis", since australo bipedality was pretty firmly established before Johanson arrived. But, as I've said, focussing on an individual is meaningless. Scientific hypotheses are not tied to the loudest mouth, but to the evidence. Johanson made an enormous contribution by discovering the Hadar fossils. But the fossils, and the data they contain, are not his. They are everyone's (and if you think that most paleoanthros go into the biz for "money and fame"-well, you're even more naïve than I thought possible!). The possible ancestral status of A. afarensis has gone far beyond any possible influence Johanson could have. If you don't think australos are ancestral, you are on entirely the wrong track in attempting to disprove it.

[ March 31, 2002: Message edited by: Ergaster ]</p>

Ergaster

Part three of three (sigh)

Irrelevant (and that would be DR Johanson). Facts are facts, regardless of whom you are responding to. Since it is the data that count and not anyone's "motivations", it is a waste of time to delve into them. Besides, you seem to be missing an important point here: science is a competitive business. We are explicitly trained and encouraged, in seminars and reading assignments and presentations, to question and critique each other, "each other" meaning not only our classmates, but our supervisors, professors, and the other professionals in the field. We are trained to examine the data, and examine the analyses, and examine the conclusions. Believe me-if Johanson had been wrong, someone (likely plenty of someones) would have been MORE than happy to point it out. New discoveries and novel interpretations are not received unquestioningly; people are highly skeptical until the evidence either disproves or fails to disprove it.

(irrelevancies snipped)

Who cares? That's not the sum total of the evidence. In fact, it doesn't even matter.

He didn't. Lucy was clearly bipedal without it. If you do not understand how everyone knows this, that is merely an indication of your own limitations.

Now you're just being ridiculous.

…

Since Johanson is hardly all of paleoanthropology, who cares? It doesn't make australos any less bipedal.

So does this preconceived idea of yours dictate that you spout off about stuff you know nothing about? I've never understood that part.

You seem to be painting with a pretty broad brush, here. You have made at least three errors of fact in those two sentences, and at least two of inference.

BZZZZZTT!! Sorry. Wrong answer. It seems that your preconceptions have managed to blind you to reality (or at least, severely compromise your ability to read…); as you have abundantly demonstrated throughout, you have no clue as to what the actual debates are about, and yet you blithely carry on as if you know what you are talking about. Is humiliating yourself in public a prerequisite to creationism?

Ah, well…you have conflated two issues, here. The first is a) DID humans descend from ape-like ancestors? The answer is: absolutely. The evidence, from a diverse range of disciplines, is unequivocal about that.

The second is: b) WHICH species of australo did we descend from? That is a harder question to answer because fossils don't come out of the ground with genealogies attached. We can, and do, construct some pretty solid hypotheses, however, and much of the ongoing work in paleoanthropology is in testing those hypotheses. It is specious, and quite wrong, though, to pretend that lack of evidence for the exact ancestor is the same thing as lack of evidence that humans evolved. The latter hasn't been an issue for over 100 years.

Sarcasm gets you nowhere. Are you asking because you actually want to know, or are you intending to completely ignore whatever evidence you get?

Well duh….

Not lately…..

I addressed this faux pas in another post. I'll link to it here rather than go over it all again. It's the third post down.

<a href="http://iidb.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=58&t=000250&p=8" target="_blank">http://iidb.org/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=58&t=000250&p=8</a>

Oh great. A creationist quoting a creationist who cites another creationist. I'm sorry I asked….

Looking forward to the next installment….

Deb

[ March 31, 2002: Message edited by: Ergaster ]</p>

faded_Glory

Only one word: WOW !!!

This is a stonker of a thread (at least the last couple of pages). Bait, thanks ever so much for playing the 'straight man' that allows Ergaster and Oolon to land so many punches. I understand a lot more now about the details of Australopitheci and how they compare to apes and humans.

Impressive stuff.

fG

lpetrich

Ergaster, thank you for going to the trouble to respond in detail. I find it very interesting to see what the anatomical evidence is.

It's interesting to think of the Piltdown hoax in this context. It was essentially a composite of a human cranium and an orangutan jawbone, with some filing down to fit and some staining to make the bones look old.

The first "find", in 1905, aroused lots of skepticism that it was a composite, but many of the skeptics were quieted by the second "find" in 1915. The same accidental composite happening twice was too much for coincidence.

The reverse combination -- upright walking with a smaller brain -- was what the real fossils had manifest in the 1930's and 1940's, and Piltdown got viewed as an oddball case and even illegitimate by some paleoanthropologists.

It might be interesting to collect opinion on Piltdown between the "finding" of these "fossils" and their exposure. From what I recall of it, its biggest supporters were British, maybe out of "we want one too" sentiment, while paleoanthropologists elsewhere were more skeptical. However, it was not the fault of any British paleoanthropologist that Britain had been covered by a few kilometers of glacier for much of the last 2 million years.

Kosh

Deb, I want to have your baby. <img src="graemlins/notworthy.gif" border="0" alt="[Not Worthy]" />
No wait, that's impossible. How 'bout I just
buy you a beer, eh?

Oolon Colluphid

Hi Ergaster! Just wanted to add my own ‘Wow!’ and <img src="graemlins/notworthy.gif" border="0" alt="[Not Worthy]" /> Superb posts. Only problem: I suspect that Ron has scarpered.

Should he still be around, there’s just one bit I’d like to emphasise.

This, I think, is very important. This shoulder ability is called (IIRC) brachiation. It’s the reason tennis players can serve and cricketers can bowl as they do. And it is why apes can swing from their arms below branches. It is only found in apes and man. We are clearly ‘designed’ with this same shoulder mobility.

Now, if we were created as bipeds, why on earth do we need this particular arrangement? I suppose one could get panglossian and say that the creator wanted us to be able to play cricket. But if so, there are countless other features demonstrated in the natural world we might benefit from too, but which we don’t have.

Which leads me to another bit of Ron’s that got overlooked in the flurry of A’pith stuff:

Quite how that helps you is anyone’s guess. You’re the one claiming that we were separately created. That would leave the creator free to incorporate into the pinnacle of his creation as many Good Ideas as would fit. Yet in all these senses we are either far less efficient than these others, or else do not possess them at all. We are unnecessarily limited. And we are limited in just the ways we would expect if decent with modification were the answer. You could as well ask why sheep can’t see right in front of their noses, and so couldn’t judge the distance from one branch to another. They can’t because they almost never need to. It is more use to them to watch for predators all around themselves. Evolution can only work with what’s available at each generation, and will only improve things if the ‘improvement’ is of some benefit.

There is no pressing need for an arboreal creature to smell prey or to hear the high squeaks of small mammals some miles away, to hear the low rumbles elephants use, to taste traces of blood in water, to see infrared, ultraviolet or tiny movements on the ground hundreds of feet below, to tear raw meat with our teeth. We do have plenty of features which are useful for our (former) lifestyle: binocular vision for branch-to-branch distance judging, we can smell well enough to judge if food is spoiled, we have colour vision to judge the ripeness of fruit, and so on, and above all, we have intelligence, which allows us to make up for these ‘deficiencies’ should we need to.

Nope, you still have it backwards. Why would a creator create something so feeble? To repeat my point, given a free hand to model things however he wished, a creator could reduce starvation by allowing us to photosynthesise, made our brains grow even faster after birth and so saved women from the numerous dangers of birthing such a huge head, and let us appreciate flowers even more by seeing in ultraviolet.... and so on in a near-endless list. As to these 'regressions'...

-- Speed? I’m damn sure I could outrun a chimp if it had to run bipedally. Natural selection says the advantages of having your hands free outweighed the disadvantage of not using them for locomotion. It may catch me up on all fours... but It’ll be me holding a sharpened stick when it gets to me.

-- Strength? For what? If you’re strong enough to fashion said sharp stick, you can achieve more with it than you can by brute strength alone. Could a physically much-stronger-than-humans group of chimps bring down a mammoth?

-- Teeth? Teeth for what? A chimp’s teeth are just as feeble as ours at grinding up large quantities of plant matter, compared to a cow; nor can they mince raw flesh as well as cats’ carnassials. Since chimps do in fact eat both raw meat and plant matter, should they not have gone extinct? If, say, the teeth of Homo habilis were so puny that they should have led to its extinction, then these puny teeth would have killed the lineage stone dead at the start, and we shouldn’t find so many of them as fossils. They evidently did work well enough – and that’s all that counts. And you don’t need sharp teeth if you’ve got a sharp stone, and a sharp stone is more replaceable, and you can have different sizes for different tasks.

-- Hair? But we do have hair on top, where the sun is hottest on an upright creature. Having less elsewhere lets you cool down quicker with sweat. Nor do our infants need to cling to it – we have our hands free to hold them. Funny, though, how babies have a grasping reflex at birth, though there’s no hair to grasp, isn’t it?

-- Most of our natural defences and weapons? Like, being able to plan and work co-operatively, to use our hands to pick up weapons, to see further than any quadruped of a similar size, and so on, are of no use in this regard?

-- Apes evolved from man? And, uh, ‘regressed’ in intelligence? Once again, a fundamental lack of understanding. Evolution isn’t about progress. Nothing now alive is ‘better’ or ‘worse’ than anything else alive too. By merely being here, it demonstrates that every single one of its ancestors had whatever it took to survive and reproduce in its environment.

So Ron, are you coming back?

TTFN, Oolon

Baloo

Deb,

"..." (i.e. words fail) <img src="graemlins/notworthy.gif" border="0" alt="[Not Worthy]" />

-Baloo