Piltdown and the search for Human Ancestors

[mark kennedy]

So now your reasoning is "there's no way Turkana Boy was a modern ape, therefore it was a human." Are you serious?

A skull 900cc is not within the range of apes and it is well within that of humans. The low end is 800cc and the high end is 2000 so I am being perfectly serious.

Do you have any reason to believe that God couldn't have created hominids that were neither modern-ape nor human?

I have every reason to conclude that he didn't create ape-men or derived men from apes.

A 900cc cranial capacity on a 1.6m tall skeleton does not make a human, any more than an 8cm-long skull on a 2m-long canine skeleton would not make for a convincing Great Dane.

Virtually every part of the boy is human right down to the teeth which have no basis of comparison to apes.

The range of human cranial capacities has been taken into consideration.

Sure you did, so what is the range of cranial capacity? I have 800cc to 2000cc for modern humans, what have you got besides a chart based on a random sampling and a median average?

I believe this is called a "switch-and-bait", whether or not Turkana Boy could have evolved from apes or into a human, or whether or not Turkana Boy could have displayed human behaviour, is irrelevant to whether or not Turkana Boy was anatomically a H.sap. Nowhere have I claimed that Turkana Boy would have been an ape or would have grunted and went about naked, he could have been making tools or speaking English for all I care and I wouldn't have known. But even that would not have made him anatomically a H.sap.

You have no clue about what a unique human feature is do you? Turkana Boy comes painfully close to his Homo habilis ancestors and this creates a major problem for TOE whether you know it or not, whether you want to admit it or not. The jump from the Homo habilis to Homo Erectus fossils is nothing less then a brain twice the size. This is classic Darwinism, you are not making a scientific arguement you are simply pointing something out that is beyond the median average:

"But how can a scientist infer history from single objects? This most common of historical dilemmas has a somewhat paradoxical solution. Darwin answers that we must look for imperfections and oddities, because any perfection in organic design or ecology obliterates the paths of history and might have been created as we find it. This principle of imperfection became Darwin's most common guide. ... I like to call it the "panda principle" in honor of my favorite example -- the highly inefficient, but serviceable, false thumb of the panda." [Stephen J. Gould, "Evolution and the Triumph of Homology, or Why History Matters," American Scientist 74 (1986)]

"The dynamics would not change, he would still be off any chart of human growth, and the issue here is not just his height but his cranial capacity which is simply out of the range of adult humans."

Now you are making baseless generalities using a graph of median averages from a random sampling. Anything that does not fall within the range of your graph cannot be human. Tell me something, if the cranial capacity of a skull is 1600cc is it still human?

Homo sapiens Anatomically modern man, although this designation (without the subspecific moniker sapiens is usually reserved for archaic forms. Some scientists recognize several subspecies, including H. s. mapaensis in Asia and H. s. heidelbergensis in Europe and Africa. Homo sapiens is believed to have originated in Africa by 500,000 BP and spread across the Old World. A third subspecies, Homo sapiens neanderthalis, represents a highly specialized form adapted to the rigors of glacial Europe and western Asia that was extinct by 30,000 BP.
Homo sapiens sapiens Us. Modern human beings. Probably arose in Africa around 150,000 years ago. The only form of Homo known to have dispersed to the New World. Occurred in Australia by 50,000 BP; North America probably by 18,000 BP, and known from Tierra del Fuego, South America, by 11,000 BP.http://www.radford.edu/~swoodwar/CLASSES/GEOG303/humnglos.html#Hssapiens

There is not a definition to be had in all these links and you seem to have assembled them at random. If you want to look at the features of Turkana Boy and the other Homo erectus fossils well and good but don't just post a link and call it a definition.

"Go away and then come back"? I really don't know what you're trying to say here, you'll have to elaborate.

Just how is Turkana Boy within the range of human cranial capacities?


When preparing the error bars I utilised Wikipedia information as stated #325: Wikipedia says the range is 1100cc-1700cc; I take it to mean the standard deviation is about 100cc (range ~= 6 std. dev.), and note that my average is lower than the given average of 1400 (which means I am being generous to the creationists).

That is based on a median average, the range goes from 800cc to close to 2000cc.

"The range of cranial capacities for fossil humans is then in line with the range of cranial capacities for modern humans. Modern humans have a cranial capacity range from about 700 cubic centimeters all the way up to about 2200cc (*). This range- a factor of three- is an amazing spread and most unusual in the biological world. It is recognized that this spread had virtually nothing to do with intelligence, because human intelligence is more dependent on how the brain is organized than on sheer brain size alone." -Marvin Lubenow, "Bones of Contention" [/QUOTE]

 

[Chalnoth]

"The range of cranial capacities for fossil humans is then in line with the range of cranial capacities for modern humans. Modern humans have a cranial capacity range from about 700 cubic centimeters all the way up to about 2200cc (*). This range- a factor of three- is an amazing spread and most unusual in the biological world. It is recognized that this spread had virtually nothing to do with intelligence, because human intelligence is more dependent on how the brain is organized than on sheer brain size alone." -Marvin Lubenow, "Bones of Contention"

Human heights also vary quite a lot. I can guarantee you that modern humans with 900cc cranial capacities are much shorter than 1.6m as adults.

Edit:
And then, even if you somehow think you can sweep the cranial capacity under the rug, as other posters have noticed, that is not the only difference between the skeleton and modern humans.

 

[shernren]

A skull 900cc is not within the range of apes and it is well within that of humans. The low end is 800cc and the high end is 2000 so I am being perfectly serious.

Source, please, and qualifications as to whether this range is for humans or adult humans. I_Love_Cheese has already provided a source that shows the distribution among even children (let alone 1.6m adolescent) not even going anywhere near 900cc, so I'm waiting for your source.

I have every reason to conclude that he didn't create ape-men or derived men from apes.

That you might conclude that God did not derived men from apes might be logical given your beliefs. But why couldn't God have created other hominids? Does God have a thing against hominids? Do you have a conclusive list of "things God didn't create" somewhere in your Bible?

Virtually every part of the boy is human right down to the teeth which have no basis of comparison to apes.

Except the brow ridges, heavy jaws, and small cranial capacity?

Sure you did, so what is the range of cranial capacity? I have 800cc to 2000cc for modern humans, what have you got besides a chart based on a random sampling and a median average?

Chart's good enough, I have qualified exactly where my data comes from and just what it applies to (i.e., the relationship between age, height and cranial capacity). Can you qualify your sources? Is your range for modern humans a range from childhood to adulthood, or a range applicable to adult humans? And is this cranial capacity correlated to height, or not?

You have no clue about what a unique human feature is do you? Turkana Boy comes painfully close to his Homo habilis ancestors and this creates a major problem for TOE whether you know it or not, whether you want to admit it or not. The jump from the Homo habilis to Homo Erectus fossils is nothing less then a brain twice the size. This is classic Darwinism, you are not making a scientific arguement you are simply pointing something out that is beyond the median average:

"But how can a scientist infer history from single objects? This most common of historical dilemmas has a somewhat paradoxical solution. Darwin answers that we must look for imperfections and oddities, because any perfection in organic design or ecology obliterates the paths of history and might have been created as we find it. This principle of imperfection became Darwin's most common guide. ... I like to call it the "panda principle" in honor of my favorite example -- the highly inefficient, but serviceable, false thumb of the panda." [Stephen J. Gould, "Evolution and the Triumph of Homology, or Why History Matters," American Scientist 74 (1986)]

Again, I have not raised the question at all of whether or not humans did evolve from Turkana Boy or from other hominids.

Now you are making baseless generalities using a graph of median averages from a random sampling. Anything that does not fall within the range of your graph cannot be human. Tell me something, if the cranial capacity of a skull is 1600cc is it still human?

Please quantify these terms:

median average
random sampling

They have strict statistical usages which make no sense within the context of your sentence.

Why not? It falls right within 3s.d. of my graph using a mean of 1300cc, and using Wikipedia's mean of 1400cc (which moves Turkana even farther off the graph) it is within 2s.d.

There is not a definition to be had in all these links and you seem to have assembled them at random. If you want to look at the features of Turkana Boy and the other Homo erectus fossils well and good but don't just post a link and call it a definition.

Those are links to sites pertaining to anthropology, if you have a better definition by all means put it up. A Homo sapiens is simply an anatomically modern human and Turkana Boy simply does not match the proportions of an anatomically modern human.

"Go away and then come back"? I really don't know what you're trying to say here, you'll have to elaborate.

That is based on a median average, the range goes from 800cc to close to 2000cc.

"The range of cranial capacities for fossil humans is then in line with the range of cranial capacities for modern humans. Modern humans have a cranial capacity range from about 700 cubic centimeters all the way up to about 2200cc (*). This range- a factor of three- is an amazing spread and most unusual in the biological world. It is recognized that this spread had virtually nothing to do with intelligence, because human intelligence is more dependent on how the brain is organized than on sheer brain size alone." -Marvin Lubenow, "Bones of Contention"

Again you are fudging the issue, just what age group / height group is this 700cc-2200cc range taken over? And do any of the 880cc humans have skulls that have heavy brow ridges and large jaws?

 

[mark kennedy]

"It was once thought that the evolution of the genus Homo was an example of anagenesis, the continual and gradual change of one parent species into its daughter species in a linear fashion. As the fossil record began to expand and more early human fossils were found dating to the period between 2 million and 1 million years ago, some questions as to the validity of this hypothesis were raised. "

The Homo habilis Debate

The canidates for the ancestors of KNM-15000 'Turkana Boy' would be ER 1470 (2 mya) and ER 1813 ER (1.9 mya)

"1470 has a cranial capacity of 775cc, where ER 1813 has a cranial capacity of only 510cc (which is above the australopith average, but well below the accepted 600cc cutoff for Homo)" (Homo habilis debate, Smithsonian Human Family Tree)

Then you have Turkana Boy at 1.6 mya with a cranial capacity of about 900cc. It sounds like a neat linear progession doesn't it? There is just one major problem, the habilines were little more then apes and with the advent of ergaster/erectus this dramatic spike in cranial capacity just stops. Mind you, the previous canidates for human ancestors are not all that different from apes while the Homo erectus fossils are pretty much human.

This is followed by a long period of stasis that pretty much continues to this day. You keep asking me about the cranial capacity so lets look at that. Two anthropologists teamed up with two paleontologists to do endocast comparisons of Homo erectus fossils, Turkana Boy and modern Chinese cranial capacities. This is what they reported:

"Compared with the ZKD, Indonesian, and African Homo erectus specimens, Hexian has more morphological features in common with ZKD. Principal component analyses indicate that Hexian is closest to the ZKD Homo erectus compared with the modern Chinese and other Homo erectus, but its great breadth distinguishes it. Metric analyses show that the brain height, frontal breadth, cerebral height, frontal height, and parietal chord from Homo erectus to modern humans increased, while the length, breadth, frontal chord, and occipital breadth did not change substantially."

Endocranial Cast of Hexian Homo erectus from South China

The Hexian and ZKD skulls are all dated between 400 ka and 500 ka with the Turkana Boy being 1.5 mya and of course modern Chinese being contemporary. Here are the measurements of the cranial capacities:

Hexian adult, 412 ka, 1,025 cc
ZKD III juvenile, 423 ka, 915 cc
ZKD II, adult, 585 ka, 1,020 cc
ZKD X, adult, 423 ka, 1,225cc
ZKD XI, adult, 423 ka, 1,015cc
ZKD XII, 423 ka, 1030cc
Sm 3, adult, 100ka, 917cc
KNM-WT 15000, juvenile, 1.5 mya, 880cc
Modern Chinese, adult, 1,140-1,540

The first thing that sticks out in my mind is that there is not a lot of variance between Turkana Boy and the Chinese Homo erectus skulls. Bear in mind we are looking at a million years of evolution and relative stasis. Notice that Sm3 is an adult with a cranial capacity of 917cc, that is pretty close to Turkana Boy.

When you are talking about the human brain you are talking about profound energetic costs associated with both it's adaptations and it's maintanance. We are not talking about a neat, linear model here, we are talking about an unprecedented leap. It would require hundreds if not thousands of mutations in hundreds if not thousands of genes. This would have started suddenly, been accomplished in an astonishingly brief period of time and ended just as abruptly.

You guys are chasing the wind with these mythical apemen fables and the genuine sceinces will prove this out over time.

 

[USincognito]

What exactly do you know, or think you know about the jaw. What about the jaw is not a question, it's a diversion. The range of human cranial capacity is between 800cc and 2000cc, you won't find many at the high or low end but it happens.

I snipped your tangental quote mining because A. you're full of it on the cranial capacity and that has been demonstrated over and over so I'm not going to play your ad nauseum games and B. I really want you to answer the question and not had wave and continue to try and tangent back to an issue you've been proven wrong about.

Explain to me how that massive jaw fits with "normal human ranges" or provide me with a medical condition which would explain why it is so massive and robust. It's a whole skull. You can't just myopically focus on the parts you (incorrectly) think fit your claims.

What about the jaw?

 

[USincognito]

"The range of cranial capacities for fossil humans is then in line with the range of cranial capacities for modern humans. Modern humans have a cranial capacity range from about 700 cubic centimeters all the way up to about 2200cc (*). This range- a factor of three- is an amazing spread and most unusual in the biological world. It is recognized that this spread had virtually nothing to do with intelligence, because human intelligence is more dependent on how the brain is organized than on sheer brain size alone." -Marvin Lubenow, "Bones of Contention"

Unbelievable. Not only are you quote mining a Creationist hack and not a medical source, but you're not even including his primary source. You're just including his prosiac assertion?

- Edit Ahhh. Good old Talk Origins

Creationist Marvin Lubenow (1992) states that the lower limit of human cranial capacity is 700 cc, a much lower figure than anyone else. His source is Races, Types and Ethnic Groups by Stephen Molnar. Molnar says that "there are many persons with 700 to 800 cubic centimeters", but provides no source for this information, and none of his sources appear to do so either. In fact, one of his sources contradicts Molnar (and Lubenow). Tobias (1970) says that according to Dart, "apparently normal human beings have existed with brain-sizes in the 700's and 800's" (maybe Molnar's claim is a mis-statement of this), and that the smallest cranial capacity ever documented is 790 cc.

This strongly contradicts Molnar's claim that "many" modern humans have a cranial capacity below 800 cc, and Lubenow's derived claim that anything above 700 cc is a "normal" value. Instead, it appears from a variety of sources that values below 900 cc are exceptionally rare, and values below 800 cc virtually nonexistent.

 

[shernren]

"It was once thought that the evolution of the genus Homo was an example of anagenesis, the continual and gradual change of one parent species into its daughter species in a linear fashion. As the fossil record began to expand and more early human fossils were found dating to the period between 2 million and 1 million years ago, some questions as to the validity of this hypothesis were raised. "

The Homo habilis Debate

The canidates for the ancestors of KNM-15000 'Turkana Boy' would be ER 1470 (2 mya) and ER 1813 ER (1.9 mya)

"1470 has a cranial capacity of 775cc, where ER 1813 has a cranial capacity of only 510cc (which is above the australopith average, but well below the accepted 600cc cutoff for Homo)" (Homo habilis debate, Smithsonian Human Family Tree)

Then you have Turkana Boy at 1.6 mya with a cranial capacity of about 900cc. It sounds like a neat linear progession doesn't it? There is just one major problem, the habilines were little more then apes and with the advent of ergaster/erectus this dramatic spike in cranial capacity just stops. Mind you, the previous canidates for human ancestors are not all that different from apes while the Homo erectus fossils are pretty much human.

This is followed by a long period of stasis that pretty much continues to this day. You keep asking me about the cranial capacity so lets look at that. Two anthropologists teamed up with two paleontologists to do endocast comparisons of Homo erectus fossils, Turkana Boy and modern Chinese cranial capacities. This is what they reported:

"Compared with the ZKD, Indonesian, and African Homo erectus specimens, Hexian has more morphological features in common with ZKD. Principal component analyses indicate that Hexian is closest to the ZKD Homo erectus compared with the modern Chinese and other Homo erectus, but its great breadth distinguishes it. Metric analyses show that the brain height, frontal breadth, cerebral height, frontal height, and parietal chord from Homo erectus to modern humans increased, while the length, breadth, frontal chord, and occipital breadth did not change substantially."

Endocranial Cast of Hexian Homo erectus from South China

The Hexian and ZKD skulls are all dated between 400 ka and 500 ka with the Turkana Boy being 1.5 mya and of course modern Chinese being contemporary. Here are the measurements of the cranial capacities:

Hexian adult, 412 ka, 1,025 cc
ZKD III juvenile, 423 ka, 915 cc
ZKD II, adult, 585 ka, 1,020 cc
ZKD X, adult, 423 ka, 1,225cc
ZKD XI, adult, 423 ka, 1,015cc
ZKD XII, 423 ka, 1030cc
Sm 3, adult, 100ka, 917cc
KNM-WT 15000, juvenile, 1.5 mya, 880cc
Modern Chinese, adult, 1,140-1,540

The first thing that sticks out in my mind is that there is not a lot of variance between Turkana Boy and the Chinese Homo erectus skulls. Bear in mind we are looking at a million years of evolution and relative stasis. Notice that Sm3 is an adult with a cranial capacity of 917cc, that is pretty close to Turkana Boy.

When you are talking about the human brain you are talking about profound energetic costs associated with both it's adaptations and it's maintanance. We are not talking about a neat, linear model here, we are talking about an unprecedented leap. It would require hundreds if not thousands of mutations in hundreds if not thousands of genes. This would have started suddenly, been accomplished in an astonishingly brief period of time and ended just as abruptly.

You guys are chasing the wind with these mythical apemen fables and the genuine sceinces will prove this out over time.

Before directly addressing the points above, can I take this as a concession by silence that Turkana Boy could not have been an anatomically modern H.sap? There is a point to this repeated questioning.

 

[mark kennedy]

Before directly addressing the points above, can I take this as a concession by silence that Turkana Boy could not have been an anatomically modern H.sap? There is a point to this repeated questioning.

I'm still waiting for the scientific definition for the genus Homo. I'll give you a hint, the genus is hotly debated and far from certain. If you get to the article I quoted, cited and linked, after going to some trouble to find, I would be interested in your thoughts. Look forward to discussing it with you guys when you get tired of arguing in circles around these 'anatomical features' you speak of in generalities.

 

[mark kennedy]

Unbelievable. Not only are you quote mining a Creationist hack and not a medical source, but you're not even including his primary source. You're just including his prosiac assertion?

Oh that's right, creationists are never relevant even when the topic is creationism.

- Edit Ahhh. Good old Talk Origins

So you slam creationist hacks and post a link to the evolutionist hacks without making a substantive remark about either. Pedantic satire is allways a good comeback.

 

[USincognito]

Oh that's right, creationists are never relevant even when the topic is creationism.

No Mark. No matter how many times you try and change the subject we're going to keep dragging you kicking and screaming back to what's actually being discussed. The quote you mined from Lubenow was not about Creationism, it was about ranges of cranial capacity in humans. I would think one would consult an on-line medical dictionary rather a quote mined from a lay book by a Creationist hack who didn't even cite a primary source himself.

So you slam creationist hacks and post a link to the evolutionist hacks without making a substantive remark about either. Pedantic satire is allways a good comeback.

You without shame sir, utterly without shame. Unlike your quote from Lubenow, the quote I took from Talk Origins actually had citations showing where Lubenow got his data set from. In case you missed it.

Creationist Marvin Lubenow (1992) states that the lower limit of human cranial capacity is 700 cc, a much lower figure than anyone else. His source is Races, Types and Ethnic Groups by Stephen Molnar. Molnar says that "there are many persons with 700 to 800 cubic centimeters", but provides no source for this information, and none of his sources appear to do so either. In fact, one of his sources contradicts Molnar (and Lubenow). Tobias (1970) says that according to Dart, "apparently normal human beings have existed with brain-sizes in the 700's and 800's" (maybe Molnar's claim is a mis-statement of this), and that the smallest cranial capacity ever documented is 790 cc.

Maybe when you start providing citations in your quotes that you mine from books you can take such a smug condescending attitude, but until then, please, just actually respond to the substance or slink away quietly.

Like will you ever get around to actually addressing that massive jaw on supposedly "normal human" Turkana Boy?

 

[shernren]

I'm still waiting for the scientific definition for the genus Homo. I'll give you a hint, the genus is hotly debated and far from certain. If you get to the article I quoted, cited and linked, after going to some trouble to find, I would be interested in your thoughts. Look forward to discussing it with you guys when you get tired of arguing in circles around these 'anatomical features' you speak of in generalities.

It's quite simple, really.

A Homo sapiens is an anatomically modern human.
Anatomically modern humans don't have 880cc skulls on 1.6m skeletons.
Turkana Boy has an 880cc skull on a 1.6m skeleton.
Therefore, Turkana Boy is not an anatomically modern human.

Can you find me a definition of Homo sapiens that works any better?

 

[USincognito]

For all this talk about how "normal" Turkana Boy is I'd make the case that were Mark correct, this would be one of the most extraordinary finds in the history of Anthropology.

What we have is the 1.5 million year old anatomically modern "normal" human skeleton of a strapping 5'2" 12 year old boy who is projected to have been around 6' at adulthood (tall even by 20th Century standards) who has one of the smallest cranial capacities ever (equal to that of a 3 or 4 year old toddler) and a massive jaw at least 5 times larger than any one I have ever seen on a human being - pathological or not.

This kid was a trifecta of the some very extreme body proportions and somehow wound up being lucky enough to die where he'd leave one of the most complete "normal" human skeletons older than 40,000 years a whopping 1.5 million years ago.

If that's anything but "normal", I don't know what is...

 

[mark kennedy]

For all this talk about how "normal" Turkana Boy is I'd make the case that were Mark correct, this would be one of the most extraordinary finds in the history of Anthropology.

What we have is the 1.5 million year old anatomically modern "normal" human skeleton of a strapping 5'2" 12 year old boy who is projected to have been around 6' at adulthood (tall even by 20th Century standards) who has one of the smallest cranial capacities ever (equal to that of a 3 or 4 year old toddler) and a massive jaw at least 5 times larger than any one I have ever seen on a human being - pathological or not.

He would have had a cranial capacity of 910cc which is well within human variation, didn't you see the comparison of Asian Homo erectus, KNM-WT 15000 and modern Chinese? It is remarkable that you missed the only real scientific comparisions in the thread. I should'nt be supprised especially when you are making so much noise about the jaw. So far I have not been able to find any direct comparisons but I thought I would offer you what I did manage to find?

"But how does this relate to the anatomical differences seen in modern humans versus non-human primates? First, the jaw muscles and their bony attachments in apes and monkeys are much larger and more powerful than in humans. At the tissue level, the researchers found that macaque chewing and biting muscles are nearly ten times as large as in humans, which correlates with the fact that MYH16 protein is made in macaques and not in humans. So maybe the "disease" is a weaker bite, raising a question as to why this mutated version of the gene could have become so widespread among modern humans.

By comparing a portion of the MYH16 gene sequence in humans to that in five other animals--quantifying the so-called molecular clock--the researchers calculated that the inactivating mutation appeared in a hominid ancestor about 2.4 million years ago, after the lineages leading to humans and chimpanzees diverged. Shortly thereafter, roughly 2.0 million years ago, the less muscled, larger brained skulls of the earliest known members of the genus Homo start to appear in the fossil record.

From this the investigators postulated that the first early hominids born with two copies of the mutated MYH16 gene would show many effects from this single mutation--most notably a reduction in size and contractile force of the jaw-closing muscles, some of which exert tremendous stress across and/or cause deposition of additional bone atop growth zones of the braincase. "The coincidence in time of the gene-inactivating mutation and the advent of a larger braincase in some early Homo populations may mean that the decrease in jaw-muscle size and force eliminated stress on the skull, which 'released' an evolutionary constraint on brain growth," says Minugh-Purvis. Indeed, aspects of the evolutionary trend of shrinking jaws and teeth, resulting in the lighter, more delicate structure found in humans today, roughly coincided with the increase in brain size characterizing the evolution of Homo over the past two million years. "​

First Protein Difference Between Humans And Primates That Correlates To Anatomical Changes In Early Hominid Fossil Record

This kid was a trifecta of the some very extreme body proportions and somehow wound up being lucky enough to die where he'd leave one of the most complete "normal" human skeletons older than 40,000 years a whopping 1.5 million years ago.

If that's anything but "normal", I don't know what is...

You don't get it do you, his skull would have had adult proportions of 900cc which makes him anatomically human in every way including brain size. This guy is dated 1.6 mya and the late Homo habilis are dated 1.9 mya. What you have is a brain size that exploded not in millions or years but in a few hundred thousand. This creates a very serious problem that would have discredited any other theory in modern science. A common ancestor gets a pass because there must be a common ancestor whether we have a scientific basis or not.

 

[Chalnoth]

But Mark, you've been shown incontrovertible evidence that humans and apes share a common ancestry (ERV's). How can you doubt that these fossils are actually partway between human and ape?

 

[shernren]

He would have had a cranial capacity of 910cc which is well within human variation, didn't you see the comparison of Asian Homo erectus, KNM-WT 15000 and modern Chinese? It is remarkable that you missed the only real scientific comparisions in the thread.

What, you mean these?

Sorry brother, but there is a wide gap between Homo erectus and modern Chinese. Those "95% prediction interval" dotted lines mean that 95% of human variation falls between those lines, roughly 1.96 std. devs., 3 std. devs. might just nudge ZKD X in but everything else looks much farther away.

I shouldn't be supprised especially when you are making so much noise about the jaw. So far I have not been able to find any direct comparisons but I thought I would offer you what I did manage to find?

"But how does this relate to the anatomical differences seen in modern humans versus non-human primates? First, the jaw muscles and their bony attachments in apes and monkeys are much larger and more powerful than in humans. At the tissue level, the researchers found that macaque chewing and biting muscles are nearly ten times as large as in humans, which correlates with the fact that MYH16 protein is made in macaques and not in humans. So maybe the "disease" is a weaker bite, raising a question as to why this mutated version of the gene could have become so widespread among modern humans.

By comparing a portion of the MYH16 gene sequence in humans to that in five other animals--quantifying the so-called molecular clock--the researchers calculated that the inactivating mutation appeared in a hominid ancestor about 2.4 million years ago, after the lineages leading to humans and chimpanzees diverged. Shortly thereafter, roughly 2.0 million years ago, the less muscled, larger brained skulls of the earliest known members of the genus Homo start to appear in the fossil record.

From this the investigators postulated that the first early hominids born with two copies of the mutated MYH16 gene would show many effects from this single mutation--most notably a reduction in size and contractile force of the jaw-closing muscles, some of which exert tremendous stress across and/or cause deposition of additional bone atop growth zones of the braincase. "The coincidence in time of the gene-inactivating mutation and the advent of a larger braincase in some early Homo populations may mean that the decrease in jaw-muscle size and force eliminated stress on the skull, which 'released' an evolutionary constraint on brain growth," says Minugh-Purvis. Indeed, aspects of the evolutionary trend of shrinking jaws and teeth, resulting in the lighter, more delicate structure found in humans today, roughly coincided with the increase in brain size characterizing the evolution of Homo over the past two million years. "​

First Protein Difference Between Humans And Primates That Correlates To Anatomical Changes In Early Hominid Fossil Record

IOW, primates not carrying this mutation (non-human) would have had extra bone deposition in brain growth areas and large jaws, while primates carrying this mutation (human) would not have those extra bone deposits.

Now, Turkana Boy had heavy brow ridges and huge jaws. Which makes him ...

You don't get it do you, his skull would have had adult proportions of 900cc which makes him anatomically human in every way including brain size. This guy is dated 1.6 mya and the late Homo habilis are dated 1.9 mya. What you have is a brain size that exploded not in millions or years but in a few hundred thousand. This creates a very serious problem that would have discredited any other theory in modern science. A common ancestor gets a pass because there must be a common ancestor whether we have a scientific basis or not.

... not anatomically human in any way, whether you consider cranial capacity vs. height, skull structure, or the presence of heavy brow ridges and a huge jaw.

 

[mark kennedy]

But Mark, you've been shown incontrovertible evidence that humans and apes share a common ancestry (ERV's). How can you doubt that these fossils are actually partway between human and ape?

The ERV arguement is based on speculation that was being made prior to the completion of the Human Genome Project. Things have changed and these tired old homology arguements run their course and this one never had much going for it. It's just like the 98-99% DNA is the same in humans and chimpanzees, it has been conclusivly proven to be false and evolutionists still propagate the idea.

Where are the HERV seqeunces located, how long are they and what is the nucloetide seqeunce identity? My guess is that you have no clue so save the tired homology arguements for the newbies.

 

[Chalnoth]

The ERV arguement is based on speculation that was being made prior to the completion of the Human Genome Project. Things have changed and these tired old homology arguements run their course and this one never had much going for it.

No they haven't. The more recent analyses have not found any ERV's that are not consistent with the phylogenic tree. Since ERV's are a form of retransposon, of course, they have found similar ERV's in different organisms that are not a tracer of common descent, as they exist in different sections of the DNA, and have found a few ERV's that have disappeared from descendent lines because that section of the DNA was removed entirely.

But there has been no case yet found where you have the same ERV at the same location that is inconsistent with the phylogenic tree, just as there has been no case found where there was an ERV missing when it was expected to be there.

Where are the HERV seqeunces located, how long are they and what is the nucloetide seqeunce identity? My guess is that you have no clue so save the tired homology arguements for the newbies.

You've already been given evidence on this, a number of times. Why persist in ignoring it?

 

[rmwilliamsll]

The ERV arguement is based on speculation that was being made prior to the completion of the Human Genome Project. Things have changed and these tired old homology arguements run their course and this one never had much going for it. It's just like the 98-99% DNA is the same in humans and chimpanzees, it has been conclusivly proven to be false and evolutionists still propagate the idea.

Where are the HERV seqeunces located, how long are they and what is the nucloetide seqeunce identity? My guess is that you have no clue so save the tired homology arguements for the newbies.

fundamentally the HERV's forming a 3rd independent cladists system is not a homology argument, certainly not like the chimp-human homology one*. the issue is how the insertions can be used via parsimonious tree software to create clades that recapitulate the existing taxonomic and protein sequence ones.

Moreover, tree topology is highly sensitive to conversion events, allowing for easy detection of sequences involved in recombination as well as correction for such events. Although other animal species are rich in ERV sequences, the specific use of HERVs in this study allows comparison of trees to a well established phylogenetic standard, that of the Old World primates. HERVs, and by extension the ERVs of other species, constitute a unique and plentiful resource for studying the evolutionary history of the Retroviridae and their animal hosts.

from: http://www.pnas.org/cgi/content/full/96/18/10254

notes:
*
a homology argument essentially lines up the relevant DNA and compares them. the HERV argument is the construction of clade trees based on insertation sites(loci) and the mutations to those provirus sequences over time and parsimonious trees created from this data. Homology(as in sequence comparsion) is only part of the later mutation data. Although you could argue that the loci are homologous, if you do so, you need to note that it is a very different type of homology, one of position not sequence.

 

[mark kennedy]

What, you mean these?

Sorry brother, but there is a wide gap between Homo erectus and modern Chinese. Those "95% prediction interval" dotted lines mean that 95% of human variation falls between those lines, roughly 1.96 std. devs., 3 std. devs. might just nudge ZKD X in but everything else looks much farther away.

These differances are marginal at best, take another look at Table 1 and lets walk through this. The Sm3 is dated 100 ka, an adult and its very close to KNM-WT 15000. The problem here is that there was a period of over 1.5 million years. This taken in the context of the unprecedented expansion from Homo habilis to Turkana Boy makes this far less cut and dried as you want to make it.

"Both Hexian and the ZKD endocasts have sagittal keels and depressed Sylvian areas (seen only on the left for Hexian), in contrast to the flat regions that characterize KNM-WT 15000 and Sm 3."

I don't know if you are following this but the differences are marginal but the simularities are striking. From 1.6 mya to 100 ka certain features are still evident and the cranial capacity is very close. Then you compare Homo habilis and they are dramatic and that is a period of about 300 ka. The differences are signifigant according to the researchers:

"The differences were statistically significant for height, frontal breadth, cerebral height, frontal height, and parietal chord between Homo erectus and the modern Chinese in our sample. The height is 105.1 for the fossils (SD ¼ 5.2; range, 99.7–114.2), and 127.2 (SD ¼ 3.3; range, 119.8–135.2) for the modern Chinese. The frontal breadth is 97.4 (SD ¼ 6.1; range, 86.0–106.7) for the fossils, and 112.0 (SD ¼ 5.1; range, 102.9–122.3) for the modern Chinese. The cerebral height is 105.7 (SD ¼ 5.3; range, 98.9–116.2) for the fossils, and 121.8 (SD ¼ 4.9; range, 110.9–133.8) for the modern Chinese. The frontal height is 77.0 (SD ¼ 6.3; range, 66.0–88.2) for the fossils, and 91.5 (SD ¼ 3.6; range, 86.1–99.9) for the modern Chinese. The parietal chord is 90.0 (SD ¼ 4.5; range, 82.9–95.9) for the fossils, and 105.5 (SD ¼ 3.7; range, 97.9–114.1) for the modern Chinese. These five calculations separate Homo erectus from the modern Chinese in our sample."

If you want to talk about the differences I think that would be a good way to go with this.

IOW, primates not carrying this mutation (non-human) would have had extra bone deposition in brain growth areas and large jaws, while primates carrying this mutation (human) would not have those extra bone deposits.

I'm still trying to track down the direct comparisons but it seems odd that the dental work is fully evolved while the jaw is still enlarged. Add to that the fact that the development of the jaw is tied to the emergance of Homo erectus this creates some real puzzles.

Now, Turkana Boy had heavy brow ridges and huge jaws. Which makes him ...

... not anatomically human in any way, whether you consider cranial capacity vs. height, skull structure, or the presence of heavy brow ridges and a huge jaw.

Not anatomically human in any way? I think you mean anatomically human in every way except. Everything except for a slightly smaller cranial capacity and some external morphological differences is far from a sweeping rejection of this skull as human.

Let's look a little closer at the differences in the brain morphology since we have the information right in front of us for now.

 

[shernren]

The ERV arguement is based on speculation that was being made prior to the completion of the Human Genome Project. Things have changed and these tired old homology arguements run their course and this one never had much going for it. It's just like the 98-99% DNA is the same in humans and chimpanzees, it has been conclusivly proven to be false and evolutionists still propagate the idea.

Where are the HERV seqeunces located, how long are they and what is the nucloetide seqeunce identity? My guess is that you have no clue so save the tired homology arguements for the newbies.

Keep ignoring this, will you: http://www.christianforums.com/showthread.php?p=27819531#post27819531

These differances are marginal at best, take another look at Table 1 and lets walk through this. The Sm3 is dated 100 ka, an adult and its very close to KNM-WT 15000. The problem here is that there was a period of over 1.5 million years. This taken in the context of the unprecedented expansion from Homo habilis to Turkana Boy makes this far less cut and dried as you want to make it.

"Both Hexian and the ZKD endocasts have sagittal keels and depressed Sylvian areas (seen only on the left for Hexian), in contrast to the flat regions that characterize KNM-WT 15000 and Sm 3."

I don't know if you are following this but the differences are marginal but the simularities are striking. From 1.6 mya to 100 ka certain features are still evident and the cranial capacity is very close. Then you compare Homo habilis and they are dramatic and that is a period of about 300 ka. The differences are signifigant according to the researchers:

"The differences were statistically significant for height, frontal breadth, cerebral height, frontal height, and parietal chord between Homo erectus and the modern Chinese in our sample. The height is 105.1 for the fossils (SD ¼ 5.2; range, 99.7–114.2), and 127.2 (SD ¼ 3.3; range, 119.8–135.2) for the modern Chinese. The frontal breadth is 97.4 (SD ¼ 6.1; range, 86.0–106.7) for the fossils, and 112.0 (SD ¼ 5.1; range, 102.9–122.3) for the modern Chinese. The cerebral height is 105.7 (SD ¼ 5.3; range, 98.9–116.2) for the fossils, and 121.8 (SD ¼ 4.9; range, 110.9–133.8) for the modern Chinese. The frontal height is 77.0 (SD ¼ 6.3; range, 66.0–88.2) for the fossils, and 91.5 (SD ¼ 3.6; range, 86.1–99.9) for the modern Chinese. The parietal chord is 90.0 (SD ¼ 4.5; range, 82.9–95.9) for the fossils, and 105.5 (SD ¼ 3.7; range, 97.9–114.1) for the modern Chinese. These five calculations separate Homo erectus from the modern Chinese in our sample."

If you want to talk about the differences I think that would be a good way to go with this.

Mark, I honestly don't get you.

Firstly, a difference of something like 5 standard deviations is not marginal. In Z-testing, getting a test statistic 5 standard deviations away from the null mean is enough to sink a null hypothesis at any meaningful significance level. Look at my annotations:

Taking a 95% confidence range as 2 std. devs., and the dotted lines as representing that confidence range (by all means, if there is another way to interpret "95% individual prediction interval" do tell me, I'm no researcher XD), ZKD X falls right on a 4-std. dev. line with just about a 0.0032% chance of being human. Marginal? Yeah, the chances of Homo erectus all being anatomically modern human and yet having skulls so stubbornly far away from the human regime is marginal.

Also, the comparison in the passage cited is between Homo erectus and modern Chinese, I have no idea where you get the idea of a comparison between Homo erectus and Homo habilis. Unless you intend to say that modern Chinese are habilines, in which case I as a modern Chinese will get pretty mad.

I'm still trying to track down the direct comparisons but it seems odd that the dental work is fully evolved while the jaw is still enlarged. Add to that the fact that the development of the jaw is tied to the emergance of Homo erectus this creates some real puzzles.

Fair enough.

Now, Turkana Boy had heavy brow ridges and huge jaws. Which makes him ...

Not anatomically human in any way? I think you mean anatomically human in every way except. Everything except for a slightly smaller cranial capacity and some external morphological differences is far from a sweeping rejection of this skull as human.

Let's look a little closer at the differences in the brain morphology since we have the information right in front of us for now.

If you want to examine the cranial proportions instead, fine. But being 4-5 standard deviations away from the human norm does not count as being "slightly smaller".