Another new hominid fossil

[philadiddle]

Does the cranial capacity of all animals (for those who have it) increase with time?

If there is an advantage it will increase, if not, then there's no reason for it to increase.

 

[Mallon]

Does the cranial capacity of all animals (for those who have it) increase with time?

Nope.

 

[mark kennedy]

I wouldn't invest too much in the etymology of a name. Hippopotamus literally means "river horse", but it's most certainly not a horse.
Besides, humans are apes, too.

The term is often, though not always, used in counter-distinction to African apes. While it is not a taxonomic category if it's an ape size brain its an ape in that sense.

Turkana Boy actually dates to 1.6 million years, making it 180-450 thousand years younger than Australopithecus sediba. Regardless, even if I grant you that Homo ergaster was contemporaneous with A. sediba, it still makes no difference concerning the identification of A. sediba as an ape with very human features. It may not be a direct ancestor to the human species (we have no way of knowing that), but it is certainly more closely related to humans than to chimps, again, because it shares more features in common with humans. Indeed, all Australopithecus do.

First of all you don't have to 'grant' me anything, those are the dates recognized by paleontologists. More importantly, it has a chimpanzee size brain as do most of the Homo habilis fossils. Homo ergaster is fully human with a cranial capacity within the range of human cranial volumn. This hold true for Taung and far too many of the supposed transitional fossils and the glaring fact that chimpanzee ancestors are nearly non-existent should be telling us something. The most important human feature is largely ignored, there is a reason for that, Louis Leaky and Raymond Dart being the chief architects of the Homo habilis myth.

What makes Australopithecus a chimp ancestor when it shares more features in common with humans? Are you arguing that chimps are descended from humans?
Check out this article in the American Biology Teacher (specifically, see Table 1):
http://www.nabt.org/websites/instit...y_teacher/2010/February 2010/FebABTonline.pdf

I have long realized that chimpanzee ancestors were bipedal and much larger then modern chimpanzee. The fact that this biology teacher completely bypassed the skull speaks volumes for the longevity of the Leaky/Dart slight of hand. Completely ignoring the most important anatomical feature for humans they contrive this homology argument that replace the Piltdown myth. The Cerebral Rubicon remains uncrossable since human ancestors had neither the time nor the means to nearly triple the size and complexity such a highly conserved vital organ.

"Lucy" (A. afarensis) shares 14 skeletal characters in common with 'lower' apes, and 22 in common with humans. A. sediba is even more human-like for the reasons I listed above. Australopithecus may have a chimp-like cranial capacity, but it most other respects, it is like a human.

Did you know the bed Lucy was removed from was dated 188,000 years old? I've seen these comparisons before and they are just another homology argument that refuses the inverse logic.

We don't know where the chimp ancestors are yet. We've got some teeth, but that's about it. If their current ecology is any clue, chimps likely evolved in the jungles where fossilization is exceedingly rare (too many decomposers, not much in the way of sedimentation). One thing is for sure: Australopithecus isn't a chimp ancestor. It can't be. The genus as a whole takes on a more human appearance with time, not a more chimp-like appearance.

Yes we do have chimpanzee ancestors, we have Taung, A. sediba and Lucy. The problem is that everytime a chimpanzee ancestor is dug up it's automatically one of our ancestors.

As I've shown, A. sediba can only be considered a chimp if you look only at cranial capacity and ignore everything else. In most respects, the skull of A. sebida is very human-like.

It's more or less robust, nothing more. Again, chimpanzee ancestors were larger and probably bipedal and that is where it ends. The fact that you continue to ignore the cranial capacity and that this fossil has never been and never will be even considered as a chimpanzee ancestor should be telling us something of the deceptive use of homology arguments. Just like with the Piltdown hoax people see what they want to see.

 

[mark kennedy]

If there is an advantage it will increase, if not, then there's no reason for it to increase.

The advantage is an effect not a cause. In order for the cranial capacity to increase a dramatic overhaul of highly conserved genes would be required in a very short space of time. For instance:

At least one highly conserved regulatory gene would have had to have 18 substitutions in a gene that has not changed significantly since the Cambrian Explosion:

"The developmental and evolutionary mechanisms behind the emergence of human-specific brain features remain largely unknown. However, the recent ability to compare our genome to that of our closest relative, the chimpanzee, provides new avenues to link genetic and phenotypic changes in the evolution of the human brain. We devised a ranking of regions in the human genome that show significant evolutionary acceleration. Here we report that the most dramatic of these ‘human accelerated regions’, HAR1, is part of a novel RNA gene (HAR1F) that is expressed specifically in Cajal– Retzius neurons in the developing human neocortex from 7 to 19 gestational weeks, a crucial period for cortical neuron specification and migration. HAR1F is co-expressed with reelin, a product of Cajal–Retzius neurons that is of fundamental importance in specifying the six-layer structure of the human cortex. HAR1 and the other human accelerated regions provide new candidates in the search for uniquely human biology."

The 118-bp HAR1 region showed the most dramatically accelerated change, with an estimated 18 substitutions in the human lineage since the human–chimpanzee ancestor, compared with the expected 0.27 substitutions on the basis of the slow rate of change in this region in other amniotes. Only two bases (out of 118) are changed between chimpanzee and chicken, indicating that the region was present and functional in our ancestor at least 310 million years (Myr) ago. No orthologue of HAR1 was detected in the frog (Xenopus tropicalis), any of the available fish genomes (zebrafish, Takifugu and Tetraodon), or in any invertebrate lineage, indicating that it originated no more than about 400Myr ago​

(Nature, August 2006)​

What's the big difference? this is the big difference:

FIGURE 2. Comparative neuroanatomy of humans and chimpanzees. (Genetics and the making of Homo sapiens. Nature April 2003)​

This will help to put the timeline in perspective:

A. Afarensis with a cranial capacity of ~430cc lived about 3.5 mya.
A. Africanus with a cranial capacity of ~480cc lived 3.3-2.5 mya.
P. aethiopicus with a cranial capacity of 410cc lived about 2.5 mya.
P. boisei with a cranial capacity of 490-530cc lived between 2.3-1.2 mya.
OH 5 'Zinj" with a cranial capacity of 530cc lived 1.8 mya.
KNM ER 406 with a cranial capacity of 510cc lived 1.7 million years ago.​

Right around the time frame we are talking about:

"The skeleton was about 1.60 m (5 ft 3 in) tall, although he might have been 68 kg (150 lb) and 1.85 m (6 ft 1 in) tall had he lived to adulthood. The total skeleton is made up of 108 bones accounted for. The cranial capacity of Turkana Boy was about 880 cc, although if he had lived to adulthood, it would have been about 910 cc"​

(Turkana Boy, Wikipedia)

Hexian 412,000 years old had a cranial capacity of 1,025cc.
ZKD III (Skull E I) 423,000 years old had a cranial capacity of 915cc.
ZKD II (Skull D I) 585,000 years old had a cranial capacity of 1,020cc
ZKD X (Skull L I) 423,000 years ago had a cranial capacity of 1,225cc
ZKD XI (Skull L II) 423,000 years ago had a cranial capacity of 1,015cc
ZKD XII (Skull L III) 423,000 years ago had a cranial capacity of 1,030cc
Sm 3 >100,000 years ago had a cranial 917cc
KNM-WT 15000 (Turkana Boy) 1.5 million years ago had a cranial capacity of 880cc
(Source: Endocranial Cast of Hexian Homo erectus from South China, AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 130:445–454. 2006)​

Finally here is why it is a challenge to Darwinian evolution according to Charles Darwin:

If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case. No doubt many organs exist of which we do not know the transitional grades, more especially if we look to much-isolated species, round which, according to my theory, there has been much extinction. Or again, if we look to an organ common to all the members of a large class, for in this latter case the organ must have been first formed at an extremely remote period, since which all the many members of the class have been developed; and in order to discover the early transitional grades through which the organ has passed, we should have to look to very ancient ancestral forms, long since become extinct. (Darwin, Origin of Species. Chapter 6 - Difficulties on Theory)​

To date I have seen no honest treatment of these facts by evolutionists. That why these homology arguments are inheritantly disingenuous since they purposely deny the inverse logic that should be intuitively obvious.

Have a nice day
Mark

 

[lucaspa]

Your response will fit the second question on this diagram:

Why does the the capacity of modern human (close to the zero line to the right) have such a wide spread?

Better sampling of both sexes and different ages. H. sapiens females show sexual dimorphism with regard to brain volume -- H. sapiens heads and thus brain volumes are smaller in females. Also, there are more H. sapiens fossils which include teenagers who have not yet reached their full growth.

 

[lucaspa]

The advantage is an effect not a cause.

The advantage in the "struggle for existence" is a cause in the changing of the population.

In order for the cranial capacity to increase a dramatic overhaul of highly conserved genes would be required in a very short space of time.

That isn't the case. Because cranial capacity is dependent on Hox genes, you only need a small change in the Hox gene to get a very large morphological change. This is because the effect of the Hox gene is multiplied because of the effect on all the downstream genes that are involved in determining morphology.

At least one highly conserved regulatory gene would have had to have 18 substitutions in a gene that has not changed significantly since the Cambrian Explosion

Sorry, Mark, but you are working from analogy. You don't know that the Hox genes involved in cranial capacity require 18 changes. All you know is that the HAR1F gene has 18 substitutions since the human-chimp split. You do know that the gene did not have substitutions before that. But "highly conserved" does not necessarily mean "cannot change". You are misusing those terms. For some genes, yes, small changes will produce dramatic negative effects. Those are "highly conserved" in that changes in them tend to destroy function.

But then there are "highly conserved" in that the selection pressures are such that there is no need to change. It's not that there are dramatic negative effects on the individual, but rather that whatever changes happen are not going to be adaptive in the environment. Having a much more complex cortex is did not provide a significant advantage for species between chicken and chimps. But for the evolving hominids, it did.

What's the big difference? this is the big difference:

Please be specific. There are several differences between the chimp and human brain in the pictures.


[/quote]

This will help to put the timeline in perspective:

A. Afarensis with a cranial capacity of ~430cc lived about 3.5 mya.
A. Africanus with a cranial capacity of ~480cc lived 3.3-2.5 mya.
P. aethiopicus with a cranial capacity of 410cc lived about 2.5 mya.
P. boisei with a cranial capacity of 490-530cc lived between 2.3-1.2 mya.
OH 5 'Zinj" with a cranial capacity of 530cc lived 1.8 mya.
KNM ER 406 with a cranial capacity of 510cc lived 1.7 million years ago.
​

Right around the time frame we are talking about:

"The skeleton was about 1.60 m (5 ft 3 in) tall, although he might have been 68 kg (150 lb) and 1.85 m (6 ft 1 in) tall had he lived to adulthood. The total skeleton is made up of 108 bones accounted for. The cranial capacity of Turkana Boy was about 880 cc, although if he had lived to adulthood, it would have been about 910 cc"
​

(Turkana Boy, Wikipedia)

Hexian 412,000 years old had a cranial capacity of 1,025cc.
ZKD III (Skull E I) 423,000 years old had a cranial capacity of 915cc.
ZKD II (Skull D I) 585,000 years old had a cranial capacity of 1,020cc
ZKD X (Skull L I) 423,000 years ago had a cranial capacity of 1,225cc
ZKD XI (Skull L II) 423,000 years ago had a cranial capacity of 1,015cc
ZKD XII (Skull L III) 423,000 years ago had a cranial capacity of 1,030cc
Sm 3 >100,000 years ago had a cranial 917cc
KNM-WT 15000 (Turkana Boy) 1.5 million years ago had a cranial capacity of 880cc
(Source: Endocranial Cast of Hexian Homo erectus from South China, AMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY 130:445–454. 2006)[/quote]

What's the problem? From 2.5 Mya to 1.6 Mya there is an increase of 430 to 910 cc. The Paranthropus genus doesn't count because it is a dead end. So that is ~ a 480 cc increase in about 1 million years over at least 2 speciations (afarensis to habilis and habilis to ergastor). H. ergastor evolved into H. erectus in Asia. The species remained fairly constant ofer the next 1.2 million years.
​

Finally here is why it is a challenge to Darwinian evolution according to Charles Darwin:

If it could be demonstrated that any complex organ existed, which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down. But I can find out no such case. No doubt many organs exist of which we do not know the transitional grades, more especially if we look to much-isolated species, round which, according to my theory, there has been much extinction. Or again, if we look to an organ common to all the members of a large class, for in this latter case the organ must have been first formed at an extremely remote period, since which all the many members of the class have been developed; and in order to discover the early transitional grades through which the organ has passed, we should have to look to very ancient ancestral forms, long since become extinct. (Darwin, Origin of Species. Chapter 6 - Difficulties on Theory)
​

To date I have seen no honest treatment of these facts by evolutionists.

You're not looking? Or professional evolutionists don't feel the need to explain something that is obvious?

 

[lucaspa]

Homo ergaster is fully human with a cranial capacity within the range of human cranial volumn.

Ergastor is not "fully human". The shape of the skull (and thus the brain inside), is different from H. sapiens. Being within the "range" is misleading. A bell-shaped curve can be very wide. What you need to do is look at the mean and standard deviation to determine whether you have one population or two. When you look at the bell-shaped curves of cranial capacity for H. ergastor and H. sapiens, it is clear that they do belong to 2 different populations.

This hold true for Taung and far too many of the supposed transitional fossils and the glaring fact that chimpanzee ancestors are nearly non-existent should be telling us something. I have long realized that chimpanzee ancestors were bipedal

The problem with that is that the fossils near the chimp-human split (A. ramidus, Toumai, etc.) are not bipedal.

The Cerebral Rubicon remains uncrossable since human ancestors had neither the time nor the means to nearly triple the size and complexity such a highly conserved vital organ.

Notice that most of the structures are conserved. It's not that humans added a lot of structures in the brain. Plus, most of the "structures" are simply configurations of the same type of tissue found elsewhere in the brain.

I would remind you that it only takes one base substitution in one gene to make an entire tail.

Yes we do have chimpanzee ancestors, we have Taung, A. sediba and Lucy. The problem is that everytime a chimpanzee ancestor is dug up it's automatically one of our ancestors.

Actually, not automatic. The first thought is that it could be a chimp ancestor. But I find it interesting that you are arguing for an evolutionary ancestor for chimps but denying one for humans. Aren't you saying that it is very possible to trace an evolutionary lineage for chimps but impossible to trace one for humans? If so, then you are saying that humans are products of special creation but chimps are not. Right?

Of course, there are the transitional individuals linking afarensis to habilis. Then habilis to ergastor, then ergastor to sapiens (and ergastor to neanderal).

Again, chimpanzee ancestors were larger and probably bipedal and that is where it ends.

Why would they be bipedal?

The fact that you continue to ignore the cranial capacity and that this fossil has never been and never will be even considered as a chimpanzee ancestor

Look at the tables. Sediba has derived characteristics of humans. That is, characteristics that H. ergastor has but chimps do not. So why would you think it should be considered a chimp ancestor? Besides you need that in order to deny human evolution?

 

[Mallon]

The term is often, though not always, used in counter-distinction to African apes. While it is not a taxonomic category if it's an ape size brain its an ape in that sense.

We were debating here whether the etymology of a genus or species name has any bearing whatsoever on its systematic or phylogenetic status. I'll just stress that it does not and leave it at that. Just because Australopithecus literally means "southern ape" does not mean that it cannot be more closely related to humans than to other apes. Likewise, just because Hippopotamus literally means "river horse" does not mean that it is closely related to horses.

First of all you don't have to 'grant' me anything, those are the dates recognized by paleontologists. More importantly, it has a chimpanzee size brain as do most of the Homo habilis fossils. Homo ergaster is fully human with a cranial capacity within the range of human cranial volumn. This hold true for Taung and far too many of the supposed transitional fossils and the glaring fact that chimpanzee ancestors are nearly non-existent should be telling us something. The most important human feature is largely ignored, there is a reason for that, Louis Leaky and Raymond Dart being the chief architects of the Homo habilis myth.

I'm having a hard time following you, here, since it's not always clear what you're referring to.
The dates that you cited aren't the ones recognized by palaeontologists. You said that Turkana Boy (H. ergaster) dates to between "1.95 million and 1.78 million years" (or rather that it was contemporaneous with Australopithecus sediba from that time), but palaeontologists actually accept a date of 1.6 million years for Turkana Boy, meaning that it was not contemporaneous with A. sediba.
It's also not true that either Turkana Boy (if that's what "it" refers) or H. habilis have chimp-sized cranial capacities. Chimp cranial capacities vary from 275-500 cubic centimetres (cc). Turkana Boy had a cranial capacity of 880 cc. H. habilis' cranial capacity ranges from 500-800 cc. Their brain sizes are clearly greater than those of chimps.
Moreover, it isn't true that H. ergaster had "fully human" sized brains either. The earliest H. ergaster specimens range from 700-900 cc and the later ones range from 900-1100 cc. By comparison, human brains typically vary between 1040 and 1595 cc. It's pretty obvious that where there's overlap in brain size, H. ergaster occupies only the lowest end of the human scale.
These oversights strike me as very problematic for your argument above because there is no dichotomy in brain size where you think there is one.

I have long realized that chimpanzee ancestors were bipedal and much larger then modern chimpanzee. The fact that this biology teacher completely bypassed the skull speaks volumes for the longevity of the Leaky/Dart slight of hand. Completely ignoring the most important anatomical feature for humans they contrive this homology argument that replace the Piltdown myth. The Cerebral Rubicon remains uncrossable since human ancestors had neither the time nor the means to nearly triple the size and complexity such a highly conserved vital organ.

I'm having a hard time following you here. The author of the article I linked to (a palaeontologist) didn't "bypass the skull". His table 1 refers to nine features of the skull (mostly relating to the teeth and mandible).
But assuming you're referring to the brain as "the most important anatomical feature for humans", then you're right, the author didn't address that. The reason for this is because "Lucy" -- the skeleton he was working with -- doesn't have much of a braincase preserved (not because the author was ignoring this part of the skull).
Let's look at other specimens of Australopithecus afarensis, though: The average cranial capacity is about 438 cc, which is well within the range of chimps. In this sense, A. afarensis has a brain size more like that of a chimp than a human. But so what? There's more to an animal than just its brain. And 22 of the 36 features listed in the article's Table 1 link Lucy to humans instead of chimps (this number is still 22 out of 37 if we include 'braincase size' as one of the traits). Since the majority of the traits are human-like, it follows that "Lucy" is more like humans than chimps. Large brain size evidently evolved after the split between A. afarensis and Homo.

Did you know the bed Lucy was removed from was dated 188,000 years old?

No, I didn't know that. Can you please provide a citation to the peer-reviewed article that made that claim? I would like to verify it.

I've seen these comparisons before and they are just another homology argument that refuses the inverse logic.

I don't know what your problem is with homology arguments since you yourself are making them. Anytime you compare braincases between species, you are making a homology statement. It doesn't make sense for you to criticize me of something you do regularly.
Regardless, you're ignoring my question. If "Lucy" is a chimpanzee ancestor, then why does she share 22 out of 36 of the skeletal traits listed in the American Biology Teacher paper in common with humans? Note that these characters aren't just related to the hips and legs, but to the entire skeleton, including the jaws, so the resemblance between humans and what you term "chimp ancestors" isn't simply convergence due to bipedalism.

Yes we do have chimpanzee ancestors, we have Taung, A. sediba and Lucy. The problem is that everytime a chimpanzee ancestor is dug up it's automatically one of our ancestors.

As I've shown here several times, "Taung", A. sediba and "Lucy" cannot be chimp ancestors because they are more like humans than chimps. And the changes you're proposing aren't simply related to losing bipedalism because they affect the teeth and jaws, too. I would suggest more ways of testing your hypotheses, but given that YECs reject the fundamentals of geology (Steno's Rules, atomic decay, etc.), I don't think they would be meaningful to you.

It's more or less robust, nothing more. Again, chimpanzee ancestors were larger and probably bipedal and that is where it ends. The fact that you continue to ignore the cranial capacity and that this fossil has never been and never will be even considered as a chimpanzee ancestor should be telling us something of the deceptive use of homology arguments. Just like with the Piltdown hoax people see what they want to see.

I'm not ignoring cranial capacity. I admit that Australopithecus tend toward chimp-sized brains. But there's a lot more to these fossils than just brains, and it is you who is ignoring the rest of the skeleton. It is you who is getting hung up on cranial capacity. It is you who is subjectively making it the single-most important anatomical criterion separating humans from chimps, despite the fact that the fossil record shows a smooth increase in cranial capacity with time. The big push towards human-sized brains occurred after the split between Australopithecus and Homo, but that doesn't somehow negate the many other anatomical characters that link Australopithecus with Homo, as you seem to think.

 

[lucaspa]

.
But assuming you're referring to the brain as "the most important anatomical feature for humans",

But it's questionable whether you can refer to the brain as "the most important anatomical feature for humans". It's one we like to think separates us from other species, but our dentition also does that. So does our bipedality. So does the shape of our throat and the FOXP2 gene that allows for fine vocal control. The list goes on and on.

I don't know what your problem is with homology arguments since you yourself are making them.

You noticed that too! Mark is making homology arguments between the Lucy brain volume and that of chimps. So Mark's homology argument goes that since the brain volume sizes are homologous, then Lucy must be an ancestral chimp.

I'm not ignoring cranial capacity. I admit that Australopithecus tend toward chimp-sized brains. But there's a lot more to these fossils than just brains, and it is you who is ignoring the rest of the skeleton. It is you who is getting hung up on cranial capacity.

Mark is sounding like the old-time anthropologists. The old theory was that hominidsd got large brains before they became bipedal. But Lucy and A. africanus, A. ramidus, etc. show that bipedality came first. Then came larger brains. But then Mark inconsistently argues that chimps had bipedality a long time ago but lost it. And supposedly the hominid lineage retained it? But that doesn't make sense. Chimps do not have the modifications of the bones from bipedality to knuckle walking. Instead, the modifications go the other way. Lucy's pelvis is a modification of the ape pelvis going to the Homo pelvis, not going from Homo pelvis to chimp pelvis.

despite the fact that the fossil record shows a smooth increase in cranial capacity with time.

Yeah, that puzzles me about Mark's argument, too. He quotes Darwin about small successive changes and that is what the graph shows for brain volume, but somehow he thinks that "smooth increase" is against Darwin.

The big push towards human-sized brains occurred after the split between Australopithecus and Homo,

Which is against the previous theory that increased brain size came first. I can't help wonder what Mark considers an ancestor to H. ergastor. Or does he think God zapped H. ergastor into existence in their present form?

 

[philadiddle]

Hey Mark, could I get a quick reply to post #24?

 

[Mallon]

But it's questionable whether you can refer to the brain as "the most important anatomical feature for humans". It's one we like to think separates us from other species, but our dentition also does that. So does our bipedality. So does the shape of our throat and the FOXP2 gene that allows for fine vocal control. The list goes on and on.

Agreed. One must take a total-evidence approach.

You noticed that too! Mark is making homology arguments between the Lucy brain volume and that of chimps.

Agreed. He also accepts homology arguments as they apply to the ungulate-whale transition and to a number of other evolutionary transitions. I don't know why he suddenly has a problem with them as they apply to humans and chimps. (Well, actually, I do. It's because he will only accept homology arguments insofar as they support his preconvictions about the Bible.)

Yeah, that puzzles me about Mark's argument, too. He quotes Darwin about small successive changes and that is what the graph shows for brain volume, but somehow he thinks that "smooth increase" is against Darwin.

I think a lot of Mark's confusion stems from a conflation of pattern and process in evolution.

Which is against the previous theory that increased brain size came first. I can't help wonder what Mark considers an ancestor to H. ergastor. Or does he think God zapped H. ergastor into existence in their present form?

I would guess the latter, but Mark would have to clarify just what his beliefs are.

 

[Mallon]

Bumping this up for mark.

 

[mark kennedy]

Guys, as intrigued as I am I really don't have a lot of time for this right now. I'm be home in just over a month and we can chase this around the mulberry bush then. I really don't think this is anything new, you are begging the question of cause by assuming the effect of a bigger and better brain. By cause I mean the molecular mechanism responsible for the three-fold expansion of the human brain from that of apes.

Think about it a minute. our latest 'ancestor' is uncovered with a chimpanzee size brain just under 2 mya. Within a couple a hundred thousand years our supposed ancestors would have 100% human features except for a slightly smaller cranial capacity. Why this giant leap in evolution does not raise an eyebrow baffles me.

Oh yea, the homology argument you guys are shooting the breeze about. I wouldn't really have a problem with it if you would honestly accept the inverse logic. If things in common is evidence of common ancestry then differences are evidence against. Can't eat your cake and have it guys.

Thanks for the bump Mallon but I just don't have a lot of time for this right now, sorry.

Grace and peace,
Mark

 

[Mallon]

Think about it a minute. our latest 'ancestor' is uncovered with a chimpanzee size brain just under 2 mya. Within a couple a hundred thousand years our supposed ancestors would have 100% human features except for a slightly smaller cranial capacity. Why this giant leap in evolution does not raise an eyebrow baffles me.

Again, this is a logical fallacy. We have fossil, morphological, and molecular evidence that humans are closely related to chimps, and your reason for rejecting that evidence is because you can't fathom how the brain could evolve so rapidly. That's a classic argument from personal incredulity. Nevermind the fact that you've stated elsewhere that you consider yourself a "radical evolutionist".
And nevermind the fact that we've actually come a long way in understanding the rapid evolution of the human brain. Here are a couple of recent articles for your perusal:
PLoS Biology: Molecular Insights into Human Brain Evolution
http://www.picb.ac.cn/Comparative/pdf/2006a.pdf
Origins of the human brain - Google Books
Molecular evolution of microcephalin, a gene determining human brain size -- Wang and Su 13 (11): 1131 -- Human Molecular Genetics
Sometimes, given the contrary way you speak, it's like you're not even aware this work is being done. You say we have no idea how the brain could evolve so quickly, yet you never address the pile of research that has already accumulated on the subject!

Oh yea, the homology argument you guys are shooting the breeze about. I wouldn't really have a problem with it if you would honestly accept the inverse logic. If things in common is evidence of common ancestry then differences are evidence against. Can't eat your cake and have it guys.

Thanks for finally explaining what you mean by "inverse logic" as it applies to homology. I've been asking you to do this for a while.
In fact, in cladistics, differences are evidence against homology. We can test a priori hypotheses of homology by designing a character matrix that contains numerous characters (including the one of interest), running a parsimony/maximum likelihood/Bayesian analysis, and seeing how the character of interest plots on the resulting cladogram. If it originates once on the cladogram (i.e., the character is a synapomorphy), the homology argument for that character is supported. If it appears multiple times on the cladogram, the homology argument for that character is rejected (i.e., there is convergence). If you have no idea what I'm talking about, read this:
http://www.ib.usp.br/hennig/depinna1991.pdf
In short, your point here is moot. Both differences and similarities play a role in the scientific inference of homology.

Thanks for the bump Mallon but I just don't have a lot of time for this right now, sorry.

No worries. Looking forward to your return, mark. God bless.

 

[mark kennedy]

It's the magic of an a priori assumption, TAAA DAAAA!

Again, this is a logical fallacy. We have fossil, morphological, and molecular evidence that humans are closely related to chimps, and your reason for rejecting that evidence is because you can't fathom how the brain could evolve so rapidly. That's a classic argument from personal incredulity. Nevermind the fact that you've stated

Speaking of fallacious reasoning, you are begging the question of proof. Your latest and greatest fossil evidence is a chimpanzee ancestor and it's rather curious that you never entertained that possibility. Both the fossil and morphological evidence indicates exactly that and the fact that evolutionists propagate one thing and publish another is the strongest proof I have seen that they don't have the courage of their convictions.

Lucy was dated at 180,000 years old the only time that the bed she came out of was dated, no one cares. This one is pretty much found on the surface and no one even attempts to form a null hypothesis for it being a chimpanzee ancestor. Why? Because evolutionists desperately need the chimpanzee ancestors for their homology arguments.

that you consider yourself a "radical evolutionist".

I am a radical evolutionist because of the time allowed from Noah's Ark and the rapidity with which these limited number of creatures had to spread.

And nevermind the fact that we've actually come a long way in understanding the rapid evolution of the human brain. Here are a couple of recent articles for your perusal:

Mallon, no offense intended but I'm better read on the subject then many of the secular evolutionists and all of the TEs. That's what I have been doing on here all these years and I have yet to see a TE that can keep up with me. You guys go to the ad hominem attack right of the bat and never stop beating it like your own private punching bag. You want to know why creationists don't want to talk to you Mallon? It's because you are rude, just like all TEs you go straight to the personal attacks and never tire of the same ad hominem attacks again and again....ad infinitum, ad nauseum.

Sometimes, given the contrary way you speak, it's like you're not even aware this work is being done. You say we have no idea how the brain could evolve so quickly, yet you never address the pile of research that has already accumulated on the subject!

Ignore it?! I have literally spent days at a time tracking it down. Most of the time when an evolutionist brings up a major research paper I've already read it. I'm not chasing down every link to every article you google, I've been ran in circles like that before. I have addressed the piles of research repeatedly, systematically and formally. If you think I'm missing something and you'd like to demonstrate that fact just make a formal debate proposal and drop me a PM. You would not be the first evolultionist I refuted with the peer reviewed scientific literature they pretend to treasure and never read.

Thanks for finally explaining what you mean by "inverse logic" as it applies to homology. I've been asking you to do this for a while.

First time I've saw it but anyways, it's from an expression I liked in a Biology lecture. It goes something to the order of, 'the inverse logic is intuitively obvious'. Now as to these fallacious homology arguments Mallon, do you accept the inverse logic or are you going to beg the question of proof on your hands and knees?

In fact, in cladistics, differences are evidence against homology. We can test a priori hypotheses of homology by designing a character matrix that contains numerous characters (including the one of interest), running a parsimony/maximum likelihood/Bayesian analysis, and seeing how the character of interest plots on the resulting cladogram. If it originates once on the cladogram (i.e., the character is a synapomorphy), the homology argument for that character is supported. If it appears multiple times on the cladogram, the homology argument for that character is rejected (i.e., there is convergence). If you have no idea what I'm talking about, read this:
http://www.ib.usp.br/hennig/depinna1991.pdf
In short, your point here is moot. Both differences and similarities play a role in the scientific inference of homology.

Not so fast buddy, you have yet to admit your a priori assumption and the inverse logic of your arguments. Now if there is a clear standard of proof then I suppose I could be persuaded to learn more about these likelihood methods. The fact of the matter is evolutionists still claim that chimpanzees and humans are 98% the same in their DNA. If you can't get them to openly admit a simple fact whats the point of a mathematical formula? I mean seriously, garbage in garbage out.

No worries. Looking forward to your return, mark. God bless.

I think I might get back into this for a while when I get home. Before I left I tried the theological aspects angle and it was a dead end, basically because TEs don't have one. Off and on I dabble in presuppositional approaches (metaphysics really) but there has to be a clear definition of the propositional logic, evolutionists never do that. I want to take another run at the evidencial approach one more time, it's the only one that really works consistently.

Anyways, I have got a lot to do and I'm planning a big summer with my daughters but I'll have some time in June, see you then.

Grace and peace,
Mark

 

[Mallon]

Speaking of fallacious reasoning, you are begging the question of proof. Your latest and greatest fossil evidence is a chimpanzee ancestor and it's rather curious that you never entertained that possibility. Both the fossil and morphological evidence indicates exactly that and the fact that evolutionists propagate one thing and publish another is the strongest proof I have seen that they don't have the courage of their convictions.

Lucaspa and myself have already shown several times throughout this thread that all Australopithecus fossils share more features in common with humans than with chimps, and that the newest A. sediba is even more similar to humans than other species of Australopithecus. So to claim that Australopithecus are chimp ancestors is a claim without warrant. It seems the only reason you think Australopithecus is closer to chimps than to humans is because they have similar-sized brains. But to focus exclusively on brain size is completely arbitrary and ignores other evidence to the contrary.

Lucy was dated at 180,000 years old the only time that the bed she came out of was dated, no one cares. This one is pretty much found on the surface and no one even attempts to form a null hypothesis for it being a chimpanzee ancestor. Why? Because evolutionists desperately need the chimpanzee ancestors for their homology arguments.

I asked you before about where you got this number from and you never responded. Where was the "180,000 years" figure published? A Google search has turned up nothing.

I am a radical evolutionist because of the time allowed from Noah's Ark and the rapidity with which these limited number of creatures had to spread.

I know. And I know that you accept evolutionary scenarios like that leading from terrestrial ungulates to whales, despite the fact that we still don't have a complete understanding about how this happened (especially not in a 6000-year framework). So for you to argue that you do not accept the evolution of humans from ape ancestors because we do not yet have a full understanding about how the brain evolved seems inconsistent to me.

Mallon, no offense intended but I'm better read on the subject then many of the secular evolutionists and all of the TEs. That's what I have been doing on here all these years and I have yet to see a TE that can keep up with me. You guys go to the ad hominem attack right of the bat and never stop beating it like your own private punching bag. You want to know why creationists don't want to talk to you Mallon? It's because you are rude, just like all TEs you go straight to the personal attacks and never tire of the same ad hominem attacks again and again....ad infinitum, ad nauseum.

Where in this thread have I attacked you rather your ideas, mark?

First time I've saw it but anyways, it's from an expression I liked in a Biology lecture. It goes something to the order of, 'the inverse logic is intuitively obvious'. Now as to these fallacious homology arguments Mallon, do you accept the inverse logic or are you going to beg the question of proof on your hands and knees?

As I've said, I fully accept that, despite some similarities between species, the differences between them can be used to argue against homology. This is why we take a total-evidence approach in phylogenetic systematics and use as many morphological and genetic characters as we can to construct our character matrices. Running such a matrix through a cladistic analysis will tell us whether our a priori hypothesis about character homology is supported, and will give us a statistic about how confident we can be accepting such a statement.
Honestly, mark, I still don't understand what your problem is with homology arguments because you yourself make them. How do your homology arguments differ from my own? Please use a concrete example.

Not so fast buddy, you have yet to admit your a priori assumption and the inverse logic of your arguments. Now if there is a clear standard of proof then I suppose I could be persuaded to learn more about these likelihood methods. The fact of the matter is evolutionists still claim that chimpanzees and humans are 98% the same in their DNA. If you can't get them to openly admit a simple fact whats the point of a mathematical formula? I mean seriously, garbage in garbage out.

%age of DNA in common is not a character that can be used in a molecular cladistic analysis. Rather, a sequence of DNA (like a gene) is used and individual basepairs are compared among species and assembled into a character matrix. This is then subjected to a cladistic analysis.
Honestly, mark, you can't claim to be as well-read as you say you are if you don't understand even the basics of how phylogenies are inferred. And you certainly can't critique it in any meaningful way. If you want to educate yourself on the subject, please check out Willi Hennig's "Phylogenetic Systematics" book. He's the grandfather of the cladistic methodology.

 

[Melethiel]

Oh, are we back to the whole "TEs don't have any theology" thing? This should be fun....*goes back to reading theology books*

 

[mark kennedy]

FIGURE 2. Comparative neuroanatomy of humans and chimpanzees. (Genetics and the making of Homo sapiens. Nature April 2003)

Lucaspa and myself have already shown several times throughout this thread that all Australopithecus fossils share more features in common with humans than with chimps, and that the newest A. sediba is even more similar to humans than other species of Australopithecus. So to claim that Australopithecus are chimp ancestors is a claim without warrant. It seems the only reason you think Australopithecus is closer to chimps than to humans is because they have similar-sized brains. But to focus exclusively on brain size is completely arbitrary and ignores other evidence to the contrary.

The fact that this thing has a chimpanzee size brain is irrelevant even though it's the greatest giant leap in our mythical lineage from the apes. To ignore the size and complexity of the human brain is a deliberate attempt to dodge the null hypothesis even Darwin accepted as a logical disproof of his theory.

I asked you before about where you got this number from and you never responded. Where was the "180,000 years" figure published? A Google search has turned up nothing.

Don't have it available right now but it was published in Nature...sorry.

I know. And I know that you accept evolutionary scenarios like that leading from terrestrial ungulates to whales, despite the fact that we still don't have a complete understanding about how this happened (especially not in a 6000-year framework). So for you to argue that you do not accept the evolution of humans from ape ancestors because we do not yet have a full understanding about how the brain evolved seems inconsistent to me.

I neither accept nor do I reject the whale evolution thing, my central focus is human evolution since that is the only issue that conflicts with Christian theology. I am pretty consistent, even atheistic materialists catch on to that about me.

Where in this thread have I attacked you rather your ideas, mark?

You started right off with it in your previous post:

Again, this is a logical fallacy. We have fossil, morphological, and molecular evidence that humans are closely related to chimps, and your reason for rejecting that evidence is because you can't fathom how the brain could evolve so rapidly. That's a classic argument from personal incredulity.

No, that's a classic ad hominem attack assuming ignorance on the part of Christians that do not swallow Darwinism whole. If you do not make the first a priori assumption of universal common descent you are assumed to be ignorant aka incredulous.

As I've said, I fully accept that, despite some similarities between species, the differences between them can be used to argue against homology. This is why we take a total-evidence approach in phylogenetic systematics and use as many morphological and genetic characters as we can to construct our character matrices. Running such a matrix through a cladistic analysis will tell us whether our a priori hypothesis about character homology is supported, and will give us a statistic about how confident we can be accepting such a statement.

First tell me plainly, do you accept that if things in common (homologies) are proof for common ancestry the differences are proof against? Then we can get into these cladistic analysis.

Honestly, mark, I still don't understand what your problem is with homology arguments because you yourself make them. How do your homology arguments differ from my own? Please use a concrete example.

How about Darwin's?

The theological premise in this argument -- that the apparent uniformity of certain biological patterns is inconsistent with the freedom of a creator to act as he wishes -- is nowhere better illustrated than in Darwin's book on the "contrivances" of orchids. After reviewing the homologies of orchids and ordinary flowers, Darwin appeals to our intuitions about what God would have done in this case:

Can we feel satisfied by saying that each Orchid was created, exactly as we now see it, on a certain "ideal type:" that the omnipotent Creator, having fixed on one plan for the whole Order, did not depart from this plan: that he, therefore, made the same organ to perform diverse functions -- often of trifling importance compared with their proper function -- converted other organs into mere purposeless rudiments, and arranged all as if they had to stand separate, and then made them cohere? Is it not a more simple and intelligible view that all the Orchideae owe what they have in common, to descent from some monocotyledonous plant....? (Charles Darwin, On the Various Contrivances by Which Orchids Are Fertilized by Insects)​

The Place of Darwinian Theological Themata in Evolutionary Reasoning

%age of DNA in common is not a character that can be used in a molecular cladistic analysis. Rather, a sequence of DNA (like a gene) is used and individual basepairs are compared among species and assembled into a character matrix. This is then subjected to a cladistic analysis.
Honestly, mark, you can't claim to be as well-read as you say you are if you don't understand even the basics of how phylogenies are inferred. And you certainly can't critique it in any meaningful way. If you want to educate yourself on the subject, please check out Willi Hennig's "Phylogenetic Systematics" book. He's the grandfather of the cladistic methodology.

How about this one?

"The developmental and evolutionary mechanisms behind the emergence of human-specific brain features remain largely unknown. However, the recent ability to compare our genome to that of our closest relative, the chimpanzee, provides new avenues to link genetic and phenotypic changes in the evolution of the human brain. We devised a ranking of regions in the human genome that show significant evolutionary acceleration. Here we report that the most dramatic of these ‘human accelerated regions’, HAR1, is part of a novel RNA gene (HAR1F) that is expressed specifically in Cajal– Retzius neurons in the developing human neocortex from 7 to 19 gestational weeks, a crucial period for cortical neuron specification and migration. HAR1F is co-expressed with reelin, a product of Cajal–Retzius neurons that is of fundamental importance in specifying the six-layer structure of the human cortex. HAR1 and the other human accelerated regions provide new candidates in the search for uniquely human biology."

The 118-bp HAR1 region showed the most dramatically accelerated change, with an estimated 18 substitutions in the human lineage since the human–chimpanzee ancestor, compared with the expected 0.27 substitutions on the basis of the slow rate of change in this region in other amniotes. Only two bases (out of 118) are changed between chimpanzee and chicken, indicating that the region was present and functional in our ancestor at least 310 million years (Myr) ago. No orthologue of HAR1 was detected in the frog (Xenopus tropicalis), any of the available fish genomes (zebrafish, Takifugu and Tetraodon), or in any invertebrate lineage, indicating that it originated no more than about 400Myr ago
​

(An RNA gene expressed during cortical development evolved rapidly in humans. Nature 443, 167-172 14 September 2006)​

Or these?

Gene families are groups of homologous genes that are likely to have highly similar functions. Differences in family size due to lineage-specific gene duplication and gene loss may provide clues to the evolutionary forces that have shaped mammalian genomes. Here we analyze the gene families contained within the whole genomes of human, chimpanzee, mouse, rat, and dog. In total we find that more than half of the 9,990 families present in the mammalian common ancestor have either expanded or contracted along at least one lineage. Additionally, we find that a large number of families are completely lost from one or more mammalian genomes, and a similar number of gene families have arisen subsequent to the mammalian common ancestor. Along the lineage leading to modern humans we infer the gain of 689 genes and the loss of 86 genes since the split from chimpanzees, including changes likely driven by adaptive natural selection. Our results imply that humans and chimpanzees differ by at least 6% (1,418 of 22,000 genes) in their complement of genes, which stands in stark contrast to the oft-cited 1.5% difference between orthologous nucleotide sequences. This genomic “revolving door” of gene gain and loss represents a large number of genetic differences separating humans from our closest relatives.

Explaining the obvious morphological, physiological, and behavioral traits that separate modern humans from our closest relatives, the chimpanzees, is challenging given the low level of nucleotide divergence between the two species. More than 30 years have passed since King and Wilson first pointed out this apparent paradox, saying that “the genetic distance between humans and the chimpanzee is probably too small to account for their substantial organismal differences” . To explain the paradox, King and Wilson proposed that regulatory changes rather than protein-coding mutations were responsible for the vast majority of observed biological differences. Evidence gathered since that time demonstrates that amino acid and regulatory sequence changes have both been involved in the evolution of uniquely human phenotypes.​

The Evolution of Mammalian Gene Families​

Or this?

Table 3. Estimates of mutation rate assuming different divergence times and different ancestral population sizes

4.5 mya, pop.= 10,000 mutation rate is 2.7 x 10^-8
4.5 mya, pop.= 100,000 mutation rate is 1.6 x 10^-8
5.0 mya, pop.= 10,000 mutation rate is 2.5 x 10^-8
5.0 mya, pop.= 10,0000 mutation rate is 1.5 x 10^-8
5.5 mya, pop.= 10,000 mutation rate is 2.3 x 10^-8
5.5 mya, pop.= 10,000 mutation rate is 1.4 x 10^-8
6.0 mya, pop.= 10,000 mutation rate is 2.1 x 10^-8
6.0 mya, pop.= 100,000 mutation rate is 1.3 x 10^-8

Table 4. Estimates of mutation rate for different sites and different classes of mutation

Transition at CpG mutation rate 1.6 x 10^-7
Transversion at CpG mutation rate 4.4 x 10^-8
Transition at non-CpG mutation rate 4.4 x 10^-8
Transversion at non-CpG mutation rate 5.5 x 10^-9
All nucleotide subs mutation rate 2.3 x 10^-8
Length mutations mutation rate 2.3 x 10^-9
All mutations mutation rate 2.5 x 10^-8

Rates calculated on the basis of a divergence time of 5 mya, ancestral population size of 10,000, generation length of 20 yr, and rates of molecular evolution given in Table 1.


Calculations are based on a generation length of 20 years and average autosomal sequence divergence of 1.33%
-----------------------------------------------------

Estimate of the Mutation Rate per Nucleotide in Humans (Michael W. Nachmana and Susan L. Crowella Genetics, 297-304, September 2000)​

When the actual divergence is found to be between 5% and 6% does the calculation of the mutation rate change?

Now when you digest that a little we can talk about what chimpanzees have in common with humans and what they don't.

Have a nice day
Mark

Oh, are we back to the whole "TEs don't have any theology" thing? This should be fun....*goes back to reading theology books*

Your Lutheran right?

It is also taught among us that since the fall of Adam all men who are born according to the course of nature are conceived and born in sin. That is, all men are full of evil lust and inclinations from their mothers’ wombs and are unable by nature to have true fear of God and true faith in God. Moreover, this inborn sickness and hereditary sin is truly sin and condemns to the eternal wrath of God all those who are not born again through Baptism and the Holy Spirit. Rejected in this connection are the Pelagians and others who deny that original sin is sin, for they hold that natural man is made righteous by his own powers, thus disparaging the sufferings and merit of Christ. (The Book of Concord: The Confessions of the Evangelical Lutheran Church)​

They would seem to believe in a literal Adam, does that have any theological issues that might be related to ancestry?

 

[gluadys]

Oh, are we back to the whole "TEs don't have any theology" thing? This should be fun....*goes back to reading theology books*

Your Lutheran right?

It is also taught among us that since the fall of Adam all men who are born according to the course of nature are conceived and born in sin. That is, all men are full of evil lust and inclinations from their mothers’ wombs and are unable by nature to have true fear of God and true faith in God. Moreover, this inborn sickness and hereditary sin is truly sin and condemns to the eternal wrath of God all those who are not born again through Baptism and the Holy Spirit. Rejected in this connection are the Pelagians and others who deny that original sin is sin, for they hold that natural man is made righteous by his own powers, thus disparaging the sufferings and merit of Christ. (The Book of Concord: The Confessions of the Evangelical Lutheran Church)​

They would seem to believe in a literal Adam, does that have any theological issues that might be related to ancestry?

Is sin inherited biologically, Mark? Are there DNA sequences that specify original sin?

 

[Melethiel]

Your Lutheran right?

It is also taught among us that since the fall of Adam all men who are born according to the course of nature are conceived and born in sin. That is, all men are full of evil lust and inclinations from their mothers’ wombs and are unable by nature to have true fear of God and true faith in God. Moreover, this inborn sickness and hereditary sin is truly sin and condemns to the eternal wrath of God all those who are not born again through Baptism and the Holy Spirit. Rejected in this connection are the Pelagians and others who deny that original sin is sin, for they hold that natural man is made righteous by his own powers, thus disparaging the sufferings and merit of Christ. (The Book of Concord: The Confessions of the Evangelical Lutheran Church)​

They would seem to believe in a literal Adam, does that have any theological issues that might be related to ancestry?

Nope. Adam could have just as easily been the first hominid to be endowed with a human soul, the ability to relate to God - and thus the first true human. We'll both agree, I think, that there's more to being human than physical appearance. He didn't even have to be the ONLY real human - he could easily have been the federal head of a group of humans, and so was responsible for all of them when he sinned. (This idea is quite comparable to our situation today - there isn't a "sin gene" that is responsible for our sinful nature)

Or maybe he WAS specially created, and the hominid fossils really are just human-like animals. I'm rather agnostic about the whole thing. Only thing is that there isn't a genetic bottleneck roughly 6000 years ago, which is why I think the idea of Adam being the federal head of a group of humans is more likely. But again, I'm rather agnostic about the whole deal - bottom line for me is, there was an Adam, he was the first true human, he sinned, and humanity fell. The details aren't particularly important to me (there may even have been a garden and a snake - who knows).