|
|
pleco
SFN Addict
USA
2998 Posts |
Posted - 01/23/2006 : 18:47:27
|
DNA analysis also shows they're evolving faster than humans:
http://www.msnbc.msn.com/ID/10994885
quote: While you might think of yourself as smarter than the average ape, beware: Those distant relatives of ours have a knack for evolving more quickly than we do. And by revealing this through DNA analysis, scientists have provided support for a controversial hypothesis that chimpanzees are more closely related to humans than to other species of great apes with which they're currently classified.
The findings were announced today in a study in the Proceedings of the National Academy of Sciences.
Why scientists even bother is admirable since evolution will eventually not be taught in any public school (in the USA at least).
|
by Filthy The neo-con methane machine will soon be running at full fart. |
|
|
HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 01/23/2006 : 20:51:16 [Permalink]
|
That one's interesting. If the study is valid, and if I were a scientist, I might be tempted to speculate that in the wild, chimp bands are subjected to intense competition with other bands of chimps, and increasingly with humans as well. Without speech and writing to help them with cultural strategies of competition, genetic change becomes all the more vital for survival. By comparison, our human culture and technology puts a need for genetic change on the back burner, compared to chimps.
Thank goodnees I'm not a scientist, and don't have to worry about such things. |
“Biology is just physics that has begun to smell bad.” —HalfMooner Here's a link to Moonscape News, and one to its Archive. |
|
|
UncleJ
New Member
41 Posts |
Posted - 01/23/2006 : 21:08:12 [Permalink]
|
Very interesting but please note, the really big caveat is in the last paragraph of the article
quote: However, Yi and her colleagues looked only at mutations in non-functional regions of DNA, changes that don't affect evolution. "If we looked at only those mutations that are selected, it is possible we may see different results," she said.
|
"The Church says the Earth is flat. But I know that it is round. For I have seen the shadow on the Moon. And I have more faith in a shadow than in the Church." - F. Magellan "I can't be a missionary! I don't even believe in Jebus!" - H. Simpson |
|
|
HalfMooner
Dingaling
Philippines
15831 Posts |
Posted - 01/23/2006 : 23:22:32 [Permalink]
|
quote: Very interesting but please note, the really big caveat is in the last paragraph of the article
"Big caveat," no shit! |
“Biology is just physics that has begun to smell bad.” —HalfMooner Here's a link to Moonscape News, and one to its Archive. |
|
|
Hawks
SFN Regular
Canada
1383 Posts |
Posted - 01/24/2006 : 00:03:44 [Permalink]
|
quote: Originally posted by HalfMooner
quote: Very interesting but please note, the really big caveat is in the last paragraph of the article
"Big caveat," no shit!
Not necessarily. Regions thought to be previously non-coding have in fact been found to have some functionality. |
METHINKS IT IS LIKE A WEASEL It's a small, off-duty czechoslovakian traffic warden! |
|
|
beskeptigal
SFN Die Hard
USA
3834 Posts |
Posted - 01/24/2006 : 02:25:15 [Permalink]
|
The chimp genome has much more variation than the human genome. In other words if you take all the humans we differ from each other pretty consistently by about 3 million base pairs. Chimps on the other hand differ from each other by more, and sorry but I don't know the number. What gives you the variation is how long your species has been around. Humans experienced a severe bottleneck in the past that decreased our numbers to around a mere thousand or so members. That didn't happen to chimps. I wonder if that bottleneck had some influence on the way we advanced intellectually faster than the chimps did.
I just love new discoveries. I wonder how reclassifying chimps into the human genus will go over with the "we didn't descend from no monkeys" crowd? |
|
|
filthy
SFN Die Hard
USA
14408 Posts |
Posted - 01/24/2006 : 07:18:06 [Permalink]
|
[surly, old curmudgeon] On the other hand, might it be a first, faint sign that we have become the modern version of H. neandertalesis? Hmm? [/surly old curmudgeon]
|
"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
|
|
|
beskeptigal
SFN Die Hard
USA
3834 Posts |
Posted - 01/24/2006 : 15:37:40 [Permalink]
|
quote: Originally posted by filthy
[surly, old curmudgeon] On the other hand, might it be a first, faint sign that we have become the modern version of H. neandertalesis? Hmm? [/surly old curmudgeon]
That actually, is an interesting observation. But it could be a new species, from the human branch or the chimp branch that might displace us. |
|
|
pleco
SFN Addict
USA
2998 Posts |
Posted - 01/24/2006 : 15:44:09 [Permalink]
|
quote: the human branch or the chimp branch that might displace us.
They better learn how to make nukes first, because I'm fairly sure a certain segment of our population will not stand for any competition with another sentient being. |
by Filthy The neo-con methane machine will soon be running at full fart. |
|
|
|
UncleJ
New Member
41 Posts |
Posted - 01/24/2006 : 20:26:38 [Permalink]
|
quote: Originally posted by Hawks Not necessarily. Regions thought to be previously non-coding have in fact been found to have some functionality.
Yes, the caveat necessarily still exists.
Changes in bases within coding regions have known results in the sequence of the encoded protein. We can classify the changes into categories like -those that make no changes in the amino acid sequence of the encoded protein (wobble position) -those that make conservative changes in the amino acid sequence of the encoded protein (i.e. arginine to lysine) -those that make more radical changes in the amino acid sequence of the encoded protein (i.e. arginine to valine)
The changes that take place between coding regions are of questionable effect. These changes may be in a region encoding something like a small regulatory rna or a binding site for a regulatory protein, etc. However, they may be of no discernible consequence. We currently have no easy method to tell the difference.
|
"The Church says the Earth is flat. But I know that it is round. For I have seen the shadow on the Moon. And I have more faith in a shadow than in the Church." - F. Magellan "I can't be a missionary! I don't even believe in Jebus!" - H. Simpson |
|
|
Hawks
SFN Regular
Canada
1383 Posts |
Posted - 01/24/2006 : 21:05:49 [Permalink]
|
quote: Originally posted by UncleJ
quote: Originally posted by Hawks Not necessarily. Regions thought to be previously non-coding have in fact been found to have some functionality.
Yes, the caveat necessarily still exists.
Changes in bases within coding regions have known results in the sequence of the encoded protein. We can classify the changes into categories like -those that make no changes in the amino acid sequence of the encoded protein (wobble position) -those that make conservative changes in the amino acid sequence of the encoded protein (i.e. arginine to lysine) -those that make more radical changes in the amino acid sequence of the encoded protein (i.e. arginine to valine)
The changes that take place between coding regions are of questionable effect. These changes may be in a region encoding something like a small regulatory rna or a binding site for a regulatory protein, etc. However, they may be of no discernible consequence. We currently have no easy method to tell the difference.
Don't assume that only protein-changing mutations can have considerable effects. The similarities between protein-coding genes in humans and chimps has led to the hypothesis that the largest difference between us is in fact in the regulation of the expression of these genes.
We do have have methods for evaluating if intergenic DNA sequences potentially have discernible consequences - even if we have no idea what they actually do. One of the great benefits of having the entire chimp genome sequenced is that we can use comparative genomics to compare it (the chimp genome), almost base by base, to the human genome. If sections of DNA have been conserved between the two species, then negative selection has taken place. If the same section has not been conserved, then either positive selection or drift has taken place. Coupling this knowledge to expression patterns for various proteins in the two species and you can get a pretty good picture of whether these sequences are "consequential".
Using these techniques (and others) the picture that is emerging is that what was traditionally called junk-DNA is often found to be conserved, and thus useful. Introns, originally thought to be spliced out and discarded are often highly conserved. Promoters and polymerase binding sites are sometimes conserved and sometimes not, indicating that the regulation for the expression of the relevant protein has either not changed or changed. Antisense RNA and siRNAs which do not code for proteins are important in the regulation for the expression of proteins with which they share sequence similarities. Even the post-translational glycosylation of proteins can give them altered activity.
The moral of this story: Don't assume that only protein-changing mutations can have considerable effects. |
METHINKS IT IS LIKE A WEASEL It's a small, off-duty czechoslovakian traffic warden! |
|
|
UncleJ
New Member
41 Posts |
Posted - 01/24/2006 : 21:31:34 [Permalink]
|
quote: Originally posted by Hawks The moral of this story: Don't assume that only protein-changing mutations can have considerable effects.
Um, don't believe that I did. Please show me where I made that assumption.
I simply stated that it is difficult to gauge the importance of the changes in the intergenic regions. The paper in question studies those regions. The changes observed may have anything from a negligible effect to a huge effect. The point is that we don't know so we can't easily make conclusions. That is the caveat in the study that I pointed out.
|
"The Church says the Earth is flat. But I know that it is round. For I have seen the shadow on the Moon. And I have more faith in a shadow than in the Church." - F. Magellan "I can't be a missionary! I don't even believe in Jebus!" - H. Simpson |
|
|
Hawks
SFN Regular
Canada
1383 Posts |
Posted - 01/24/2006 : 23:58:31 [Permalink]
|
quote: Originally posted by UncleJ
quote: Originally posted by Hawks The moral of this story: Don't assume that only protein-changing mutations can have considerable effects.
Um, don't believe that I did. Please show me where I made that assumption.
I simply stated that it is difficult to gauge the importance of the changes in the intergenic regions. The paper in question studies those regions. The changes observed may have anything from a negligible effect to a huge effect. The point is that we don't know so we can't easily make conclusions. That is the caveat in the study that I pointed out.
I might just have misunderstood the point of your post just before my reply? What was the point of including your explanation of the mutations in (presumably exonic) codons.
Come to think of it, the MSNBC article was not talking about non-coding regions. It was talking about non-functional regions. These two will not necessarily be the same. But then I can't find the original PNAS article, so I'm not really sure what they're talking about. |
METHINKS IT IS LIKE A WEASEL It's a small, off-duty czechoslovakian traffic warden! |
|
|
Dude
SFN Die Hard
USA
6891 Posts |
Posted - 01/25/2006 : 00:45:16 [Permalink]
|
quote: The changes that take place between coding regions are of questionable effect.
There are numerous non-coding regions that play important roles in gene expression and regulation. The expression of a specific gene at a specific stage of developement... is not something I would classify as "of questionable effect".
Anyway, they studied non-functional (read "no known function") areas. If the changes in DNA from some causes (random mutation, drift, substitution errors, and like causes) are evenly distributed among the entire genome... that caveat, while still relevent, isn't necessarily as significant as has been implied.
I'm not sure if there is any study on the distribution pattern of those random mutations across the entire genome however, on humans or chimps.
|
Ignorance is preferable to error; and he is less remote from the truth who believes nothing, than he who believes what is wrong. -- Thomas Jefferson
"god :: the last refuge of a man with no answers and no argument." - G. Carlin
Hope, n. The handmaiden of desperation; the opiate of despair; the illegible signpost on the road to perdition. ~~ da filth |
|
|
|
filthy
SFN Die Hard
USA
14408 Posts |
Posted - 01/25/2006 : 02:27:21 [Permalink]
|
Sorry -- couldn't resist it....
|
"What luck for rulers that men do not think." -- Adolf Hitler (1889 - 1945)
"If only we could impeach on the basis of criminal stupidity, 90% of the Rethuglicans and half of the Democrats would be thrown out of office." ~~ P.Z. Myres
"The default position of human nature is to punch the other guy in the face and take his stuff." ~~ Dude
Brother Boot Knife of Warm Humanitarianism,
and Crypto-Communist!
|
|
|
beskeptigal
SFN Die Hard
USA
3834 Posts |
Posted - 01/25/2006 : 03:18:40 [Permalink]
|
Did King really make that remark? |
|
|
|
|