Skip to comments.Fossil protein breakthrough will probe evolution
Posted on 11/13/2002 1:16:37 PM PST by dead
The first complete sequencing of protein from a fossil bone suggests that proteins can survive for millions of years - long enough to probe the evolution of many extinct species, including the ancestors of modern humans.
For many years, biologists have deduced evolutionary relationships from the visible features of living animals and fossils. Molecular biology has given them a new tool for living animals - comparing DNA sequences. However, DNA survives for only a short time after death, so paleontologists have been limited to comparing the shapes and sizes of the bones of extinct species.
But analyzing ancient proteins now gives them a new option, says Christina Nielsen-Marsh of the University of Newcastle, because their amino acid sequences reflect genetic codes.
The big advantage of proteins is their stability in suitable environments. Pieces of DNA large enough to sequence using sensitive amplification techniques can survive for 100,000 years in permafrost. But osteocalcin, a structural protein that bonds directly to the minerals of bone, lasts much longer.
Matthew Collins, also at Newcastle University, estimates that osteocalcin can survive for more than 100 million years at 0 °C, and for some 10 million years at 10 °C. That would be long enough to look back some six or seven million years to the last common ancestor of humans and chimpanzees.
To show the potential of their technique, Nielsen-Marsh and colleagues sequenced the amino acids in osteocalcin extracted from bones of the extinct steppe bison (Bison priscus) found in permafrost in Siberia and Alaska. Both bones are a minimum of 55,000 years old, the limit of carbon dating.
The complete sequences of amino acids exactly matched that of the modern bison (Bison bison). They differ by a single amino acid from modern cattle, which are thought to have diverged from bison at least a million years ago. Previous work has detected - but not isolated or sequenced - proteins in 120 million year old dinosaur bone.
Although osteocalcin sequences diverge slowly, they can probe evolution over millions of years. "Human evolution, is the most exciting of the possibilities," says Peter Hauschka of the Harvard Medical School, US, who worked with Nielsen-Marsh. Osteocalcins differ by a few amino acids in humans, chimps and orangutans, he says, so they could help identify the nearest living relatives of suitable fossils.
Hominid fossils are few and far between, and it could be hard to persuade anthropologists to give them up for the destructive analysis. Yet teeth also contain osteocalcin, and they are much more common fossils.
Osteocalcin itself may not be able to determine the puzzling lineages of australopithecines and humans over the past two million years, but the method could be applied to other proteins that might give a clearer picture.
Journal reference: Geology (vol 30, p 1099)
Without seeing any subsequent posts, I have to say, LOL
Please show me where I stated that, or retract it. Fossils don't show you what you think they do. I said that ID would state that fossils are fossils. You are lying.
Why would it? From an engineering design perspective, it makes perfect sense to re-use a design that works. Do you think Black and Decker invents a new electric motor every time they come up with a new power tool?
Whenever we do any engineering design at my company, we go to the AutoCAD template file and start there. We take proven designs and employ them where they are most effective. ID implies the same technique.
It seems less likely that an exact match over a range of at least 55,000 years would constitute good evidence for evolution since we have two separate species that implies at least some random mutations for one to be an evolutionary precursor of the other.
So why is the cow protein different then? I'm sure you will tell me how that makes sense from an engineering design perspective too.
Evolutionist/liberals always have the advantage...everything is made up/changes---morphs to cover their tracks/lies...
fit their desire/'life' style'!
Now I follow, thank you. Actually, I don't disagree with this at all since I see the left as abandoning the uncertianty of democracy and majority rule for the assurance technocracy and expert rule.
152 posted on 9/10/02 12:17 PM Pacific by Liberal Classic
I took a few minutes to decipher that post, and I must say I agree with a lot of what you said.
These were the Classical liberals...founding fathers-PRINCIPLES---stable/SANE scientific reality/society---industrial progress...moral/social character-values(private/personal) GROWTH(limited NON-intrusive PC Govt/religion---schools)!
Where you and I diverge is on the Evolution/Communism thing. You seem to view Darwin and evolution as the beginning of the end for enlighted, moral civilization, while I think Marx, class struggle, and the "dictatorship of the proletariat" are the true dangers.
God bless you, I think we both have a common enemy in the BRAVE-NWO.
452 posted on 9/7/02 8:54 PM Pacific by Dakmar
A couple of comments. The precision seems to be quite good. The particular protein, osteocalcin, may not be very informative or specific for short time-frames, such as 55,000 years in the case of the bison, but it will be informative for long time frames. Can you see now how that can be a useful way of extracting more information from ancient fossils?
Also, they only compared one, single protein! I wonder how many different proteins they will be able to recover from fossils.
So why is the cow protein different then?
This is the problem with ID as science. It's all over both sides of the evidence. If it works, it's re-used. If it's different, it's because the designer knows something we don't know.
What's ironic is that as more and more of these irreducibly complex features are explained, ID is starting to sound more and more like evolutionary theory.
Most proteins are recoverable for about 100,000 years (at cold temperatures). Osteocalcin is a bit unique, but they may find a few other proteins like that.
I find it amazing that evos blast christians or IDers for their 'faith' but they readily accept this article as proof of whatever they want it to be without reading the last sentence. IOW, "We are concerned that this discovery will fail to provide any conclusive evidence just as many others have failed, but we'll trumpet the discovery long enough to get in included in textbooks long after it's been discredited."
Aside from that, there is no scientific theory that doesn't fail under, at least, some circumstances. Using your criterion, there would be no science textbooks left.