Posted on 11/10/2009 10:54:53 AM PST by decimon
CORVALLIS, Ore. - Penguins that died 44,000 years ago in Antarctica have provided extraordinary frozen DNA samples that challenge the accuracy of traditional genetic aging measurements, and suggest those approaches have been routinely underestimating the age of many specimens by 200 to 600 percent.
In other words, a biological specimen determined by traditional DNA testing to be 100,000 years old may actually be 200,000 to 600,000 years old, researchers suggest in a new report in Trends in Genetics, a professional journal.
The findings raise doubts about the accuracy of many evolutionary rates based on conventional types of genetic analysis.
“Some earlier work based on small amounts of DNA indicated this same problem, but now we have more conclusive evidence based on the study of almost an entire mitochondrial genome,” said Dee Denver, an evolutionary biologist with the Center for Genome Research and Biocomputing at Oregon State University.
“The observations in this report appear to be fundamental and should extend to most animal species,” he added. “We believe that traditional DNA dating techniques are fundamentally flawed, and that the rates of evolution are in fact much faster than conventional technologies have led us to believe.”
The findings, researchers say, are primarily a challenge to the techniques used to determine the age of a sample by genetic analysis alone, rather than by other observations about fossils. In particular, they may force a widespread re-examination of determinations about when one species split off from another, if that determination was based largely on genetic evidence.
For years, researchers have been using their understanding of the rates of genetic mutations in cells to help date ancient biological samples, and in what’s called “phylogenetic comparison,” used that information along with fossil evidence to determine the dates of fossils and the history of evolution. The rates of molecular evolution “underpin much of modern evolutionary biology,” the researchers noted in their report.
“For the genetic analysis to be accurate, however, you must have the right molecular clock rate,” Denver said. “We now think that many genetic changes were happening that conventional DNA analysis did not capture. They were fairly easy to use and apply but also too indirect, and inaccurate as a result.”
This conclusion, researchers said, was forced by the study of many penguin bones that were well preserved by sub-freezing temperatures in Antarctica. These penguins live in massive rookeries, have inhabited the same areas for thousands of years, and it was comparatively simple to identify bones of different ages just by digging deeper in areas where they died and their bones piled up.
For their study, the scientists used a range of mitochondrial DNA found in bones ranging from 250 years to about 44,000 years old.
“In a temperate zone when an animal dies and falls to the ground, their DNA might degrade within a year,” Denver said. “In Antarctica the same remains are well-preserved for tens of thousands of years. It’s a remarkable scientific resource.”
A precise study of this ancient DNA was compared to the known ages of the bones, and produced results that were far different than conventional analysis would have suggested. Researchers also determined that different types of DNA sequences changed at different rates.
Aside from raising doubts about the accuracy of many specimens dated with conventional approaches, the study may give researchers tools to improve their future dating estimates, Denver said.
Collaborators on the research included scientists from OSU, Griffith University in Australia, the University of Auckland in New Zealand, Massey University in New Zealand, University of North Carolina in Wilmington, the Scripps Research Institute, and Universita’ di Pisa in Italy.
The studies were supported by the National Science Foundation, National Geographic Society, and other agencies. About the OSU College of Science: As one of the largest academic units at OSU, the College of Science has 14 departments and programs, 13 pre-professional programs, and provides the basic science courses essential to the education of every OSU student. Its faculty are international leaders in scientific research.
==Sorry GGG, but you cannot disprove the theory of evolution based upon genetic mutations by asserting that someone is mistaken about the rate of mutation
Sorry AJ, creationist have been all over this issue for about a decade. And as per usual the evos are Johnny-come-latelies. If you want to be caught up to speed, you might consider reading the following. Pay particular attention to the date range the Evos were forced to assign to the “mitochondrial eve”:
http://www.detectingdesign.com/dnamutationrates.html
Thanks for the ping!
Exactly what we've been pointing out for years.
Welcome aboard the evolutionary train! GGG is going to be angry with you for pointing out that you are an evolutionist!
I haven’t read beyond this post. However, I am certain some mouth-breathing half-wit has already howled that creationists by default must believe in a 6000 year old Earth.
You lose.
Actually, if you take a gander at the link in #41, you will see that God’s creation is designed in such a way as to ensure that even the most ardent God-hating Evos have no choice but to confirm His handiwork.
I think what is going on is they are talking about the evolution of the penguin BEFORE the DNA samples were ‘alive’. If you push back their ages then you compress the evolution that got them to that state.
See #44 and 46. GB just called you a mouth-breathing half-wit.
Actually, after reading up to post 8, I commented -
Grizzled Bear to Liberty1970; GodGunsGuts
I haven’t read beyond this post. However, I am certain some mouth-breathing half-wit has already howled that creationists by default must believe in a 6000 year old Earth.
Post Reply | Private Reply | To 8 | View Replies
Note: I made my comment at post 8 before reading any further.
Then you posted -
Tuesday, November 10, 2009 10:30:53 PM · 45 of 49
ColdWater to Grizzled Bear
You lose.
Then I pointed you to post 10 where hitchit made the obligatory 6000 year old Earth post.
Now ColdWater, are you finished behaving like a little girl who is compelled to tattle to Mommy? I hope some day reach puberty and are able to move beyond such behavior.
Usually, when you call someone a mouth-breathing half-wit, you give them a courtesy ping. OTOH, another posting etiquette is that you do not make personal attacks.
I used the term "half-wit" before reading ColdWater's post. There was an actual point to my post. I stated that I knew someone would post the tired old "new Earth" accusation before I read any further. What was your purpose of disagreeing with me in the first place? If you had read two posts down from post 8, you would have seen I was right.
Perhaps you should stop acting like a bratty pre-teen girl. Incidently, that is simply an observation about your behavior.
ColdWater doesn't seem very bothered about all this. Why don't you ping him again?
ColdWater hitchit doesn't seem very bothered about all this. Why don't you ping him again?
You seem so bothered you can't even get your names right. You are SO easy!
Actually, I’ve put in a full day’s work and I’m a bit tired. Perhaps you’ll learn what work is if you ever move out of your Mommy’s basement.
Actually, I am putting in 60 hours a week at $100 an hour. Holiday pay tomorrow.
And you're good enough, and you're smart enough, and darn it people really like you.
Glad to see you have a hobby, Sen Franken; during your spare time you brag about you super life on Free Republic.
Seriously, if you really made $100 per hour you wouldn't feel compelled to comment about it on an anonymous website.
Next, why don't you tell me about your wife, Morgan Fairchild.
Whatever makes you feel better.
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