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Author Topic:   ID/Creationism - Comparison of Human and Chimp Genomes
Meddle
Member (Idle past 1270 days)
Posts: 179
From: Scotland
Joined: 05-08-2006


Message 16 of 83 (358189)
10-22-2006 8:08 PM
Reply to: Message 4 by eggasai
10-19-2006 4:58 PM


Well mick has covered most of what I was going to say.
I've seen the supposed fusion site and the TAG seqeunces, it seems pretty convincing. There is just one problem, there is not one but 9 pericentric inversions that total 20 million base pairs (Mb). One of them is 4 Mb long and the shortest is 2 Mb long. What is more there are inversions riddled throughout the two genomes that are not easily explained as naturally occuring.
So why do you think that nine pericentric inversions to be unlikely, and which genomic rearrangements do you find hard to explain through natural processes?
Having said that, as I said in my original post, I am interested in how creationists explain the genetic evidence. As already mentioned, in the case of the human chromosome 2, we see the remnants of a second centromere region, and an additional telomere sequence. The sequence of this telomere also reverses half way though, in a head-to-head arrangement, and is flanked on either side by the same genes found on the two chimp chromosomes.
Now can this evidence be described based on creationist hypotheses?
Consider this, ERVs (actually LTRs) make up about 8% of the human genome. Do you really expect me to believe that all of this DNA is left over from germline invasions?
http://www.pnas.org/...ontent-nw/full/101/suppl_2/14572/FIG1
I have seen the comparisons and they generally take about half a dozen LTRs and use common alleles as markers. Then they give some convoluted estimate of them arriving independantly in the respective genomes. If we are going to talk about the Transposable Elements the first order of buisness is characterizing them, don't you?
As was described in the article which your linked diagram came from, ERV's are capable of propagating themselves throughout the genome, so germline invasion is not required to account for all present sequences. Also like other transposable elements, this amplification happens randomly, so to reiterate what mick asked, why do humans and chimps share the same transposable elements?

This message is a reply to:
 Message 4 by eggasai, posted 10-19-2006 4:58 PM eggasai has replied

Replies to this message:
 Message 17 by eggasai, posted 10-24-2006 7:07 PM Meddle has not replied

  
eggasai
Inactive Member


Message 17 of 83 (358622)
10-24-2006 7:07 PM
Reply to: Message 16 by Meddle
10-22-2006 8:08 PM


quote:
So why do you think that nine pericentric inversions to be unlikely, and which genomic rearrangements do you find hard to explain through natural processes?
Because of the nature of inversions, they do happen just like random mutations but have rare beneficial affects. For 9 of them to flip sections 2 Mb to 4 Mb in length without sever consequences is unrealistic. Particularly when inversions within human populations are so well characterized.
quote:
Having said that, as I said in my original post, I am interested in how creationists explain the genetic evidence. As already mentioned, in the case of the human chromosome 2, we see the remnants of a second centromere region, and an additional telomere sequence. The sequence of this telomere also reverses half way though, in a head-to-head arrangement, and is flanked on either side by the same genes found on the two chimp chromosomes.
The ERVs take up 8% of the human genome, finding a psuedo gene comparison with simular gaps is not going to be hard to do. There are simply too many assumptions here for any of this to be conclusive.
Assumption 1 - The ERVs are the result of rare germline invasions resulting in 8% of the total 240 Mb of permenantly fixed DNA.
Assumption 2 - Any difference in the same location and sequence identical can only be explained by a common ancestor.
Assumption 3- Any ERV that shows a progressive enlarged area of divergance in succeding lines of decent are the result of mutations.
The ERVs I am looking at are in psuedogenes. On the one hand if it's the same nucleotide missing in different species then it must be from common ancestor. It it's a progressive enlargement of divergance then it is a succession of mutations (why didn't the other species have mutations changing theirs I wonder). I don't buy that, for one thing I am not going to assume that a mutations account for every difference in any two genomes. Not every difference is a mutation, particularly if the gene in question just has a different amino acid there.
quote:
Now can this evidence be described based on creationist hypotheses?
The most important difference here is two assumptions creationists are not entangled in. One that mutations are writting and editing highly specific and precise sequences in the DNA. There are two explanations of a difference in a pseudogene in two species. One is that they were allways there and two they are vulnerable at the same site and viruses are looking for targets of opportunity.
Taking a random sampling of ERVs and exaggerating their signifigance is not improving anyones understanding of genetics. It is a typical homology arguement based on anecdotal evidence. Sure a tag in a place might indicate a splice and if that were the only chromosomal rearrangement this would be a slam dunk and I would be a theistic evolutionist. When it comes to the other rearrangements all I'm getting is this rethorical question from incredulity. 'How else could this happen', or 'prove this is not the explanation', is not an argument, it's an assumption.
What is infinitly more important is that you are not accounting for the divergance of humans and chimpanzees except for the Darwinian natural selection + random mutation = evolution. The fact is that mutations explain nothing except neutral affects, death, disease, disorder and an minor beneficial affect for a short space of time.
Mutations do not explain anything about the 145 Mb of differences in the chimpanzee and human genomes. The mutation rate would have to be too high, there affects would be too deleterious when they had an affect and the benefits would never have been outweighed by the costs. This becomes increasingly important when you are talking about vital organs like the brain and liver, do you have any idea how conserved the protein/regulatory genes involved are?
Edited by eggasai, : Typos and poorly worded statements.

This message is a reply to:
 Message 16 by Meddle, posted 10-22-2006 8:08 PM Meddle has not replied

Replies to this message:
 Message 18 by Dr Adequate, posted 10-25-2006 1:01 PM eggasai has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 18 of 83 (358781)
10-25-2006 1:01 PM
Reply to: Message 17 by eggasai
10-24-2006 7:07 PM


What is infinitly more important is that you are not accounting for the divergance of humans and chimpanzees except for the Darwinian natural selection + random mutation = evolution. The fact is that mutations explain nothing except neutral affects, death, disease, disorder and an minor beneficial affect for a short space of time.
Mutations do not explain anything about the 145 Mb of differences in the chimpanzee and human genomes. The mutation rate would have to be too high, there affects would be too deleterious when they had an affect and the benefits would never have been outweighed by the costs.
But this is mere assertion.
We know what the creationist dogma is. You don't need to repeat it. But can you provide a shred of a scrap of a scintilla of evidence for it?

This message is a reply to:
 Message 17 by eggasai, posted 10-24-2006 7:07 PM eggasai has replied

Replies to this message:
 Message 19 by eggasai, posted 10-25-2006 5:30 PM Dr Adequate has replied

  
eggasai
Inactive Member


Message 19 of 83 (358826)
10-25-2006 5:30 PM
Reply to: Message 18 by Dr Adequate
10-25-2006 1:01 PM


quote:
But this is mere assertion.
We know what the creationist dogma is. You don't need to repeat it. But can you provide a shred of a scrap of a scintilla of evidence for it?
On the contrary, the Chimpanzee Genome Project has provided considerable evidence that the DNA of chimps and humans is 3x more diverse then we have been led to believe. Just to see if you are cognizant of the issues, how much of the DNA in the genomes of chimpanzees and humans is the same?
My assertions will make a lot more sense if you are aware of the actual research based on the comparison of the genomes.
If you are interested in taking this to the next level take a gander at this assertion:
"Pollard's analysis showed that HAR1 is essentially the same in all mammals except humans. There were only two differences between the chicken and chimp genomes in HAR1's sequence of 118 bases (bases are subunits of DNA, the As, Cs, Ts, and Gs that spell out the genetic code). This similarity means the DNA sequence remained unchanged over hundreds of millions of years of evolutionary history, an indication that it performs a biologically important function. But sometime after the human lineage diverged from its last common ancestor with chimpanzees 5 to 7 million years ago, HAR1 began to change rather dramatically.
"We found 18 differences between chimps and humans, which is an incredible amount of change to have happened in a few million years," Pollard said."
shortened link
One of these days evolutionists will begin to see that they grossly underestimated what would be required for apes to evolve into humans. Creationist dogma huh? Tell me something then, how does a gene that is so highly conserved for 310 million years suddenly alter 18 nucleotides in a regulatory gene 118 nucleotides long?
Edited by eggasai, : rewording a statememnt
Edited by eggasai, : Thought I would throw in an interesting news articles.
Edited by AdminJar, : No reason given.

This message is a reply to:
 Message 18 by Dr Adequate, posted 10-25-2006 1:01 PM Dr Adequate has replied

Replies to this message:
 Message 20 by Dr Adequate, posted 10-25-2006 8:19 PM eggasai has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 20 of 83 (358872)
10-25-2006 8:19 PM
Reply to: Message 19 by eggasai
10-25-2006 5:30 PM


On the contrary, the Chimpanzee Genome Project has provided considerable evidence that the DNA of chimps and humans is 3x more diverse then we have been led to believe. Just to see if you are cognizant of the issues, how much of the DNA in the genomes of chimpanzees and humans is the same?
About 95%, according to the latest techniques. This figure will of course only be meaningful in context: for example, by seeing what the same techniques say about, for example, differences between chimps and gorillas.
"Pollard's analysis showed that HAR1 is essentially the same in all mammals except humans. There were only two differences between the chicken and chimp genomes in HAR1's sequence of 118 bases (bases are subunits of DNA, the As, Cs, Ts, and Gs that spell out the genetic code). This similarity means the DNA sequence remained unchanged over hundreds of millions of years of evolutionary history, an indication that it performs a biologically important function. But sometime after the human lineage diverged from its last common ancestor with chimpanzees 5 to 7 million years ago, HAR1 began to change rather dramatically.
"We found 18 differences between chimps and humans, which is an incredible amount of change to have happened in a few million years," Pollard said."
You will notice that the geneticist Pollard does not conclude from this that evolution did not take place.
One of these days ....
... as creationists have been saying for the last century-and-a-half ...
... evolutionists will begin to see that they grossly underestimated what would be required for apes to evolve into humans. Creationist dogma huh? Tell me something then, how does a gene that is so highly conserved for 310 million years suddenly alter 18 nucleotides in a regulatory gene 118 nucleotides long?
Uh ... natural selection? Remember that?
I guess that's why the fossil record shows that "suddenly" (i.e. over the course of 4 million years) the cranial capacity of the lineage under question tripled.
You are behaving as though it's a big mystery that there should be lots of evolution in humans in the genes affecting the brain. This is what we would expect to see, isn't it?

This message is a reply to:
 Message 19 by eggasai, posted 10-25-2006 5:30 PM eggasai has replied

Replies to this message:
 Message 21 by eggasai, posted 10-25-2006 8:47 PM Dr Adequate has replied

  
eggasai
Inactive Member


Message 21 of 83 (358876)
10-25-2006 8:47 PM
Reply to: Message 20 by Dr Adequate
10-25-2006 8:19 PM


quote:
About 95%, according to the latest techniques. This figure will of course only be meaningful in context: for example, by seeing what the same techniques say about, for example, differences between chimps and gorillas.
We allready know that we can expect human gene involved in brain functions to be very different then a gorilla's. The comparison of chimps and gorillas will prove very enlightning.
quote:
You will notice that the geneticist Pollard does not conclude from this that evolution did not take place.
No, evolution is assumed but this difference is not going to be explained by normative natural selection. You have the particulars in front of you and the chant of natural selection + mutations is going to come back and haunt you.
quote:
... as creationists have been saying for the last century-and-a-half ...
In that time creationism has been an intellectual and theological issue. There is the problem of decontructing Darwinism before a creationist model is possible. It will happen once people realize that there are boundries beyond which one species can transpose into an altogether different kind. Mendelian genetics is slowly providing exactly that but neither evolutionists or creationists have caught onto it yet. Creationists will have to wake up and realize that evolution is not the problem here, it's the answer. That's why evolutionists go to so much trouble to poison the well for curious creationists.
quote:
Uh ... natural selection? Remember that?
Selection acts if and only if a beneficial affect is produced. What is more natural selection is itself an effect, not a cause.
quote:
I guess that's why the fossil record shows that "suddenly" (i.e. over the course of 4 million years) the cranial capacity of the lineage under question tripled.
That must be why Homo habilis wasn't even going to be entered into the Homo catagory until they found tools in the same geological strata. He never crossed the cerebral rubicon and he was around until about 1.9 mya. With the advent of Turkana Boy and the other Homo erectus the cranial capacity jumps for less then 600cc to between 900cc and 1100cc. There are other features like the fact that Homo habilis was only about 3 foot tall and aside from bipedalism and dental work he had the body and brain of an ape. Turkana Boy, dated 1.6 mya was fully human with the exception of a cranial capacity of 900cc at full adulthood.
The point is that 4 mya the cranial capacity was just over 400cc and remained static until about 2 mya. What is more you don't go changing a brian regulatory gene involved in developing the neocortex peicemeal. 18 nucleotides represent at least 6 amino acid sequences and probably more.
You claim natural selection accounts for this? Fine, show be a beneficial affect from a mutation in a gene involved in neural functions. I'll save you the trouble of rummaging through the standard evolutionist propaganda because if they had an example it would be splattered all over the net.

This message is a reply to:
 Message 20 by Dr Adequate, posted 10-25-2006 8:19 PM Dr Adequate has replied

Replies to this message:
 Message 22 by Dr Adequate, posted 10-25-2006 11:11 PM eggasai has replied
 Message 25 by mick, posted 10-26-2006 5:08 AM eggasai has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 22 of 83 (358905)
10-25-2006 11:11 PM
Reply to: Message 21 by eggasai
10-25-2006 8:47 PM


You have the particulars in front of you and the chant of natural selection + mutations is going to come back and haunt you ...
"One day" ...
How about you save your shrill little song of triumph for when this actually happens.
It will happen once people realize that there are boundries beyond which one species can transpose into an altogether different kind. Mendelian genetics is slowly providing exactly that ...
"One day" ...
Creationists will have to wake up and realize that evolution is not the problem here, it's the answer. That's why evolutionists go to so much trouble to poison the well for curious creationists.
Ah, paranoia.
If you are seriously attempting to blame creationist ignorance on the machinations of the Evil-utionists, could I suggest that the problem lies rather closer to home?
Selection acts if and only if a beneficial affect is produced. What is more natural selection is itself an effect, not a cause.
This is true. I suspect you are looking at this ass-backwards, creationists usually are. Mutations happen all the time. Natural selection usually damps them down. When they are adaptive, they're permitted.
That must be why Homo habilis wasn't even going to be entered into the Homo catagory until they found tools in the same geological strata. He never crossed the cerebral rubicon and he was around until about 1.9 mya. With the advent of Turkana Boy and the other Homo erectus the cranial capacity jumps for less then 600cc to between 900cc and 1100cc. There are other features like the fact that Homo habilis was only about 3 foot tall and aside from bipedalism and dental work he had the body and brain of an ape. Turkana Boy, dated 1.6 mya was fully human with the exception of a cranial capacity of 900cc at full adulthood.
The point is that 4 mya the cranial capacity was just over 400cc and remained static until about 2 mya
I'm afraid I don't see the point of the point, so to speak. If you wish to argue that most of the brain evolution in the human line took place over the last 2 million years, I have no objection. But what of it? It took a lot less time than that to get from a wolve to a chihuahua.
You claim natural selection accounts for this? Fine, show be a beneficial affect from a mutation in a gene involved in neural functions. I'll save you the trouble of rummaging through the standard evolutionist propaganda because if they had an example it would be splattered all over the net.
If you will accept that it is beneficial to have the brain of a human rather than the brain of a chimpanzee, and we do seem to be doing a little better than the chimps, then, of course, the mutations which make the difference between us and chimps are mutations with beneficial effects.
Come on, this is just basic common sense. We have better brains then chimps. This is because we have better genes affecting the development and function of the brain than chimps.
You do not suppose, do you, that the eighteen differences between us and chimps in your Gene Of The Day make us less intelligent then chimps, do you? Remember, this is a gene which usually is highly conserved.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 21 by eggasai, posted 10-25-2006 8:47 PM eggasai has replied

Replies to this message:
 Message 23 by eggasai, posted 10-26-2006 1:04 AM Dr Adequate has replied

  
eggasai
Inactive Member


Message 23 of 83 (358918)
10-26-2006 1:04 AM
Reply to: Message 22 by Dr Adequate
10-25-2006 11:11 PM


Funny thing is the research I am reading is saying that the evolution of human brain genes is a special event.
One of the study's major surprises is the relatively large number of genes that have contributed to human brain evolution. "For a long time, people have debated about the genetic underpinning of human brain evolution," said Lahn. "Is it a few mutations in a few genes, a lot of mutations in a few genes, or a lot of mutations in a lot of genes? The answer appears to be a lot of mutations in a lot of genes. We've done a rough calculation that the evolution of the human brain probably involves hundreds if not thousands of mutations in perhaps hundreds or thousands of genes -- and even that is a conservative estimate."
"It is nothing short of spectacular that so many mutations in so many genes were acquired during the mere 20-25 million years of time in the evolutionary lineage leading to humans, according to Lahn. This means that selection has worked "extra-hard" during human evolution to create the powerful brain that exists in humans.
Varki points out that several major events in recent human evolution may reflect the action of strong selective forces, including the appearance of the genus Homo about 2 million years ago, a major expansion of the brain beginning about a half million years ago, and the appearance of anatomically modern humans about 150,000 years ago. "It's clear that human evolution did not occur in one fell swoop," he said, "which makes sense, given that the brain is such a complex organ."
Evidence that human brain evolution was a spe | EurekAlert!
The first step is deconstructing Darwinism and genetics is doing a fine job of that on it's own.
quote:
You do not suppose, do you, that the eighteen differences between us and chimps in your Gene Of The Day make us less intelligent then chimps, do you? Remember, this is a gene which usually is highly conserved.
You really are behind in your thinking aren't you? You know what, I'm going to let you just keep wandering in circles like this. I will toss you a bone and let you know that it would have taken hundreds, if not thousands of mutations in hundreds if not thousands of genes.
Let's just put it in perspective 83% of the protein coding genes show changes at an amino acid sequence level and I do mean 83% of all the protein coding genes in the human genome. There are at least 40,000 amino acids that diverge between chimps and humans, many in brian development genes.
This is the clicher, you don't have 25 mya to play with or even 2.5 mya. You have the space of time from Homo habilis and Turkana Boy, that's measured in the hundreds of thousands, not millions of years.
At this point it is becomeing clear that you don't even bother to read the literature. As far as I can tell you just get a few jabs and and make assinine remarks. Here's a great idea for you, when you do one of these pedantic and condescending posts of yours, have a point.

This message is a reply to:
 Message 22 by Dr Adequate, posted 10-25-2006 11:11 PM Dr Adequate has replied

Replies to this message:
 Message 24 by Wounded King, posted 10-26-2006 2:32 AM eggasai has replied
 Message 26 by mick, posted 10-26-2006 5:34 AM eggasai has replied
 Message 27 by Dr Adequate, posted 10-26-2006 3:43 PM eggasai has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 24 of 83 (358927)
10-26-2006 2:32 AM
Reply to: Message 23 by eggasai
10-26-2006 1:04 AM


Funny thing is the research I am reading is saying that the evolution of human brain genes is a special event.
You do realise that a news article or press release isn't actually 'research' per se I hope. In particular the quotes you provide such as 'nothing short of spectacular' don't actually seem to come from the research paper at all. Being a special event is not the same as being an impossible event, which is what you seem to be claiming.
Let's just put it in perspective 83% of the protein coding genes show changes at an amino acid sequence level and I do mean 83% of all the protein coding genes in the human genome. There are at least 40,000 amino acids that diverge between chimps and humans, many in brian development genes.
40,000 amino acid substitutions? That doesn't really sound like a lot. How many of those substitutions are functionally synonymous? As you yourself pointed out on the other thread such a difference could be accounted for by as little as 40,000 single nucleotide substitutions, that isn't a lot of genetic difference. If you wanted to make the point that a small amount of genetic difference can contribute to a large amount of functional difference then you seem to be making a case in favour of evolution.
This is the clicher, you don't have 25 mya to play with or even 2.5 mya. You have the space of time from Homo habilis and Turkana Boy, that's measured in the hundreds of thousands, not millions of years.
This isn't actually the case. The problem is that you think it is all about size. you are hung up on cranial capacity but cranial capacity isn't the be all and end all of the differences between human and chimp brains. So you don't require all of those thousands of mutations across thousands of genes just to make a brain 3 times bigger than a chimp's, you need them to make a human brain instead of a chimp's. So basing the interval all these mutations must occur in on the cranial capacity of Homo habilis and Turkana boy is massively fallacious.
TTFN,
WK
Edited by Wounded King, : Correction of typographical errors

This message is a reply to:
 Message 23 by eggasai, posted 10-26-2006 1:04 AM eggasai has replied

Replies to this message:
 Message 28 by eggasai, posted 10-26-2006 6:33 PM Wounded King has replied

  
mick
Member (Idle past 4986 days)
Posts: 913
Joined: 02-17-2005


Message 25 of 83 (358935)
10-26-2006 5:08 AM
Reply to: Message 21 by eggasai
10-25-2006 8:47 PM


eggasai writes:
You claim natural selection accounts for this? Fine, show be a beneficial affect from a mutation in a gene involved in neural functions. I'll save you the trouble of rummaging through the standard evolutionist propaganda because if they had an example it would be splattered all over the net.
Hi eggasai,
How about loss of the nocicepin receptor:
Facilitation of long-term potentiation and memory in mice lacking nociceptin receptors.
quote:
The peptide nociceptin (also named orphanin FQ) acts in the brain to produce various pharmacological effects, including hyperalgesia and hypolocomotion. The nociceptin receptor uses guanine-nucleotide-binding proteins to mediate the inhibition of adenylyl cyclase, the activation of potassium channels and inhibition of calcium channels. It has been shown using knock-out mice that the nociceptin receptor is not required for regulation of nociceptive responses or locomotion activity, but modulates the auditory function. Here we show that mice lacking the nociceptin receptor possess greater learning ability and have better memory than control mice. Histological analysis revealed the expression of both the nociceptin precursor and the nociceptin receptor in the hippocampus, thought to take part in aspects of learning and memory. Moreover, the receptor-deficient mice showed larger long-term potentiation in the hippocampal CA1 region than control mice, without apparent changes in presynaptic or postsynaptic electrophysiological properties. These results show that the loss of the nociceptin receptor results in a gain-of-function mutation in both the memory process and the long-term potentiation mechanism in CA1, perhaps as a result of altered intracellular signal transduction systems in neurons.
Or, the KvB1 gene
quote:
To further investigate the relationship between learning and memory, neuronal excitability, and synaptic plasticity, we have carried out experiments with aged mice that lack the auxiliary potassium channel subunit KvB1.1. In aged mice, the deletion of the auxiliary potassium channel subunit KvB1.1 resulted in increased neuronal excitability, as measured by a decrease in the post-burst afterhyperpolarization. In addition, long-term potentiation (LTP) was more readily induced in aged KvB1.1 knockout mice. Finally, the aged KvB1.1 mutants outperformed age-matched controls in the hidden-platform version of the Morris water maze.
Of course, the 18 mutations you described in your post are also examples, unless you consider them to have been deleterious, which is inconsistent with evidence of positive selection at the so called HAR loci.
Mick
Edited by mick, : No reason given.
Edited by mick, : added bold to the quotes

This message is a reply to:
 Message 21 by eggasai, posted 10-25-2006 8:47 PM eggasai has replied

Replies to this message:
 Message 30 by eggasai, posted 10-26-2006 7:05 PM mick has not replied

  
mick
Member (Idle past 4986 days)
Posts: 913
Joined: 02-17-2005


Message 26 of 83 (358936)
10-26-2006 5:34 AM
Reply to: Message 23 by eggasai
10-26-2006 1:04 AM


Where are the ID hypotheses?
eggasai writes:
The first step is deconstructing Darwinism
This is certainly the standard approach of creationists, but it is not actually the first step in effecting a paradigm shift in science. One would really want to forge a superior theory that can explain everything explained by evolutionary theory, plus some other things that evolutionary theory cannot explain. If all you want to do is "deconstruct Darwinism" but have not a single theory with which to replace it, that is hardly a constructive enterprise.
Why not give us the Intelligent Design explanation for the origin of characteristics unique to the human brain, and let us see how it stands up against the evolutionary explanation?
This thread is about the ID response to the human/chimp genome comparison, but we have heard not a single non-Darwinian hypothesis explaining the observed genome data. All we get is the standard creationist bluster, which is to claim that evolutionary theory is collapsing (just that no scientists have noticed, yet). If you have your way, and "Darwinism" is one day tossed into the grime at the back of history's fume cupboard, how are we going to explain the similarites and dissimilarities of the human and chimp genomes?
Mick

This message is a reply to:
 Message 23 by eggasai, posted 10-26-2006 1:04 AM eggasai has replied

Replies to this message:
 Message 33 by eggasai, posted 10-26-2006 7:27 PM mick has replied

  
Dr Adequate
Member (Idle past 284 days)
Posts: 16113
Joined: 07-20-2006


Message 27 of 83 (359083)
10-26-2006 3:43 PM
Reply to: Message 23 by eggasai
10-26-2006 1:04 AM


Funny thing is the research I am reading is saying that the evolution of human brain genes is a special event.
Yes. Did you read beyond the first paragraph of the paper you cited?
quote:
"It is nothing short of spectacular that so many mutations in so many genes were acquired during the mere 20-25 million years of time in the evolutionary lineage leading to humans, according to Lahn. This means that selection has worked "extra-hard" during human evolution to create the powerful brain that exists in humans.
Varki points out that several major events in recent human evolution may reflect the action of strong selective forces
The evolution of the brain was rapid; it required strong selective forces; strong selective forces were present.
The first step is deconstructing Darwinism and genetics is doing a fine job of that on it's own.
"One day" ... "one day" geneticists will agree with you.
You do not suppose, do you, that the eighteen differences between us and chimps in your Gene Of The Day make us less intelligent then chimps, do you? Remember, this is a gene which usually is highly conserved.
You really are behind in your thinking aren't you? You know what, I'm going to let you just keep wandering in circles like this. I will toss you a bone and let you know that it would have taken hundreds, if not thousands of mutations in hundreds if not thousands of genes.
Let's just put it in perspective 83% of the protein coding genes show changes at an amino acid sequence level and I do mean 83% of all the protein coding genes in the human genome. There are at least 40,000 amino acids that diverge between chimps and humans, many in brian development genes.
This is the clicher, you don't have 25 mya to play with or even 2.5 mya. You have the space of time from Homo habilis and Turkana Boy, that's measured in the hundreds of thousands, not millions of years.
At this point it is becomeing clear that you don't even bother to read the literature. As far as I can tell you just get a few jabs and and make assinine remarks. Here's a great idea for you, when you do one of these pedantic and condescending posts of yours, have a point.
This strange rant is not a reply to the quotation which precedes it.
I see you were not even able to attempt a reply to any of the other points I made.
Edited by Dr Adequate, : No reason given.

This message is a reply to:
 Message 23 by eggasai, posted 10-26-2006 1:04 AM eggasai has not replied

  
eggasai
Inactive Member


Message 28 of 83 (359114)
10-26-2006 6:33 PM
Reply to: Message 24 by Wounded King
10-26-2006 2:32 AM


One would expect there to be a choice mutation here and there. It makes sense that certain genes are going to be different but not in genes involved in the brain or liver. However, it is exactly here that you see the spectacular mutations. Sure, 40,000 amino acids don't seem like a whole lot until you take into consideration that this is 120,000 nucleotides at the very least. Not only do they have to be substituted in triplet codons but fold into meaningfull proteins. Most of the time when an indel (mutation of length) happens a stop codon is inserted, it's just as well, it would fold into a usefull protein anyway.
One of the biggest problems with most of the more dramatic mutations being in the functionally biased neural genes is the physiological costs. Even if it's an improved fittness, for say the neocortex, it still have to coordinate with the rest of the brain. Brain tissue is some of the most biologically expensive pieces of real estate in the human genome to have adaptive mutations.
Then there is this regulatory gene in the Human Accelerated Region 1. Mind you, this is one of 49 and this is the most highly divergant. Turkana Boys cranium has been compared to modern Chinese and it is only slightly smaller and as far as then can tell to internal proportions are pretty close. In Homo habilis you have an ape, 3 foot tall with a cranial capacity that is very close to chimpanzees. The point being the space between Homo habilis and Tukana Boy is simply not measured in millions of years but hundreds of thousands.
You do need hundreds, if not thousands of mutations in hundreds if not thousands of genes for this to happen. Like the Cambrian Explosion and every major epoch in evolution as natural history this is invariably the case. Major mophological adaptations in a relativly brief period of time. This is exactly what a creationist would expect, a sharp line of demarkation between originally created kinds.
Don't take my word for genes involved with neural functions, look up mutations affecting neural functions in the human brain. There is nothing indicating beneficial affects and yet it is here that the burden of proof weighs heaviest upon the evolutionist.

This message is a reply to:
 Message 24 by Wounded King, posted 10-26-2006 2:32 AM Wounded King has replied

Replies to this message:
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 Message 35 by Dr Adequate, posted 10-26-2006 7:55 PM eggasai has not replied

  
Wounded King
Member
Posts: 4149
From: Cincinnati, Ohio, USA
Joined: 04-09-2003


Message 29 of 83 (359124)
10-26-2006 7:04 PM
Reply to: Message 28 by eggasai
10-26-2006 6:33 PM


It makes sense that certain genes are going to be different but not in genes involved in the brain or liver.
Why ever not? Are all vertebrates brains identical? All mammalian brains? Plainly not, so why on earth would you not expect to see diferences?
Sure, 40,000 amino acids don't seem like a whole lot until you take into consideration that this is 120,000 nucleotides at the very least.
Could you run through your math here for me? As I pointed out in the post you were replying to 40,000 amino acid changes can be accounted for by 40,000 nucleotide substitutions. In fact if you allow single nucleotide deletions or insertions and a subsequent frame shift you could have several amino acids changed by a single nucleotide mutation. I can't concievably see where you get that you require 120,000 mutations, or rather I think I can 40,000 X the 3 nucleotides in a codon, unfortunately this calculation makes absolutely no sense whatsoever.
Not only do they have to be substituted in triplet codons
Completely wrong, what on earth gave you such an arseabout idea?
Most of the time when an indel (mutation of length) happens a stop codon is inserted, it's just as well, it would fold into a usefull protein anyway.
Most of the time, but not all of the time.
Brain tissue is some of the most biologically expensive pieces of real estate in the human genome to have adaptive mutations.
Which may be exactly why we still see such a high degree of conservation in the neural genes of many organisms and huam's appear to have had an 'accelerated evolution'. As has previously been suggested to you such high, maintenance high complexity brains are not neccessarily a fitness advantage, that they appear to have been so for man and his immediate ancestors may be why they have such an unusal pattern of evolution.
Then there is this regulatory gene in the ...... hundreds of thousands.
Just restating the same crap argument doesn't make it suddenly better. We were already discussing Har1 on another thread and I'd be glad to continue discussing it there. Once again you can't
determine an interval for the evolution of all the differences between the chimp and human neural genes, or even those ones which appear subject to positive selection, based solely on cranial capacity because cranial capacity is by no means the sole difference between chimp and human brains. If you didn't understand the argument I can explain it further, but just restating your original claim is no sort of rebuttal. All your evidence suggests is that mutations which increased the cranial capacity 3 fold occurred in this time period. How many mutations in how many genes that would require is a matter for speculation, but it certainly isn't all of the neural genes distinct in human and chimp.
Don't take my word for genes involved with neural functions, look up mutations affecting neural functions in the human brain. There is nothing indicating beneficial affects and yet it is here that the burden of proof weighs heaviest upon the evolutionist.
This is such a crap argument and creationist/IDers use it all the time. Of course the literature on neural developmental defects is extensive as opposed to the literture on 'beneficial' neural mutations because people aren't brought into hospitals because they work well but because there is some problem. Therefore there is a wealth of medical research focused on what is wrong with peoples' development.
Even to detec a 'beneficial' neural mutation would require a massive effort of genetic screenin and lineage tracing. Making such an arguemnt just suggests you haven't the faintest idea either of how the literature has got to be the way it is or of what would be required to demonstrate a beneficial neural mutation in humans. Its like all the people complaining that all the drosophila mutagenesis screens produced was embryonic lethals, completely ignoring the fact that the screens are frequently actually designed to identify embryonic lethals.
TTFN,
WK

This message is a reply to:
 Message 28 by eggasai, posted 10-26-2006 6:33 PM eggasai has not replied

  
eggasai
Inactive Member


Message 30 of 83 (359126)
10-26-2006 7:05 PM
Reply to: Message 25 by mick
10-26-2006 5:08 AM


How about loss of the nocicepin receptor:
Typical beneficial affect, for one thing it is the loss of a receptor and the other its a phamacological effect. It inhibits two processes and produces a minor behavioral advantage. We are talking about the overhaul of a regulatory gene involved in the development of the neocortex. If we were talking about gross structural changes in a gene leading to an improved feature you might have something here.
[quote]the KvB1 gene
I don't know that this is a great example of a beneficial effect or not. Again form, size and complexity isn't really involved. Instead its a lack the auxiliary potassium channel. Ultimatly this is a loss of function resulting in a slight behavioral improvement.
Interesting but hardly persuasive.
quote:
Of course, the 18 mutations you described in your post are also examples, unless you consider them to have been deleterious, which is inconsistent with evidence of positive selection at the so called HAR loci.
That's just it, these are not mutations, they are simply differences in nucleotide sequences. The only way a lineage of apes could evolve into humans is to have this alteration along with a lot of others. Remember, this is not an isolated incident, this is from one end of the genome to the other. Sure natural selection could preserve it once it happens but how does it happen is the most important question. Random mutations could not possibly pull this off, hit and miss alterations would kill the fetus in no time.

This message is a reply to:
 Message 25 by mick, posted 10-26-2006 5:08 AM mick has not replied

  
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