Posted on 10/10/2012 8:32:08 PM PDT by SunkenCiv
By comparing the specimens' ages and degrees of DNA degradation, the researchers calculated that DNA has a half-life of 521 years. That means that after 521 years, half of the bonds between nucleotides in the backbone of a sample would have broken; after another 521 years half of the remaining bonds would have gone; and so on.
The team predicts that even in a bone at an ideal preservation temperature of -5 °C, effectively every bond would be destroyed after a maximum of 6.8 million years. The DNA would cease to be readable much earlier -- perhaps after roughly 1.5 million years, when the remaining strands would be too short to give meaningful information.
"This confirms the widely held suspicion that claims of DNA from dinosaurs and ancient insects trapped in amber are incorrect," says Simon Ho, a computational evolutionary biologist at the University of Sydney in Australia. However, although 6.8 million years is nowhere near the age of a dinosaur bone -- which would be at least 65 million years old -- "We might be able to break the record for the oldest authentic DNA sequence, which currently stands at about half a million years," says Ho...
"I am very interested to see if these findings can be reproduced in very different environments such as permafrost and caves," says Michael Knapp, a palaeogeneticist at the University of Otago in Dunedin, New Zealand.
Moreover, the researchers found that age differences accounted for only 38.6% of the variation in DNA degradation between moa-bone samples. "Other factors that impact on DNA preservation are clearly at work," says Bunce. "Storage following excavation, soil chemistry and even the time of year when the animal died are all likely contributing factors that will need looking into."
(Excerpt) Read more at nature.com ...
No, I checked. Lots of math involved, maybe there’s something in Numbers?
You use your God given ability.
I’m at a loss of words.
Well... I think you start with some sand, and a quartz rock.
Go study your Bible and get back to me when you understand it. All you are supposed to know is there.
Which is it?
I’m sorry it took you this long to arrive at this position.
That was good!
Chapter and verse please?
That's nothing. He created the Universe, and did it quicker than it took them to write down the Bible.
They are the same.
I don’t wish to feud with you. I will pray for you. God bless you and may you find truth.
The truth is I think your insane, and I’m running away from you.
Great find! Thanks.
Politics and the Fourth Dimension are commonly knee-jerk, emotional topics of discussions.
This article is interesting also from the standpoint that the mechanism for the half-life is not based on radioactivity or the change in ratio between isotopes or elements.
It will be interesting to watch as other paleontologists publish half-life data on other animal species.
Amimals in Arctic permafrost from the late Pleistocene would be an excellent baseline for a climate far removed from New Zealand.
Amen!
Ancient Chinese Proverb: Wisdom is in knowing and not saying.
Why would my soul be in danger because I disagree with you?
Sounds like you have control issues.
Salvation doesn't rely on belief in a 6000 year old world. It relies on a Redeemer.
/johnny
Probably contributes, but aging is complex, and we clearly aren't close to really understanding it. There are regions, for example, called telomeres at the ends of each chromosome that protect the chromosome from degradation. These regions become shorter after each cell division, and this is thought to be one thing that contributes to aging.
It's also important to realize that DNA is also chemically modified - without changing its sequence. This is called epigenetic modification, and is incredibly important. These chemical modifications of DNA, like methylation, are what tell the cell which genes to express in that particular cell. Making stem cells from adult cells is based on altering these chemical modifications of DNA. It's certainly possible that changes in the chemical modifications of DNA contribute to aging.
In the end, nobody gets out alive, and aging is probably programmed into us. Sometimes I agree with the line for My Generation by the Who - ‘hope I die before I get old’..
If I want to raise bees (Really, I need the rib cage of a dead lion?) breed spotted sheep (Peeled hazel, poplar and chestnut trumps selective breeding? OooooKAY) or sharpen a knife (OK, iron on iron sorta works, but a grinding stone is faster) I'll look elsewhere.
We might be a bit overdue for a third iteration.
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