A group of researchers have made a discovery regarding the half-life of DNA molecules, which unfortunately means we'll never see a cloned T-Rex… probably.
A group of paleontologists have been testing 158 leg bones from three species of extinct Moa birds, a type of flightless bird native to New Zealand. The bones ranged from 600 to 8000 years old and helped the researchers determine the half-life of the DNA molecule. When kept in an average temperature of 13.1 degrees Celcius and stored in a swamp-like environment, the DNA degrades to half of it's initial structural integrity after a lowly 521 years. Even if the DNA is stored in a significantly colder temperature, with an average of -5 degrees Celcius, the group estimates DNA could only survive for roughly 1.5 million years.
Structure of the DNA molecule
DNA breaks down for a variety of reasons: external factors such as surrounding temperature, water, soil compounds, etc. will have varying effects on the molecule. The research states that with every 521 year segment, the nucleotide bonds which hold the DNA molecule together break apart, and each half-millennium which passes sees a new section of the molecular bonds crumble. Eventually, no bonds are left and the DNA molecule is completely destroyed.
So thus, the scientists have established that, though we may see a cloned mammoth some time in the future, we'll never see a T-Rex, and Jurassic Park won't be opening any time soon… Or will it? Science still has not determined the effects on DNA in more favorable environments, such as permafrost. Further more, just last year, paleontologists Mary Schweizer and Jack Horner made an amazing discovery:
Schweizer was dissolving the outermost layers of mineral from a fossilized dinosaur bone, but the acid she used in the process was much to strong and dissolved the entire bone. She expected to find nothing remaining, but what she instead encountered was translucent tubes, seemingly appearing to be blood vessels, which were flexible. Further more, she repeated the experiment and found intact cells. Whether DNA can be extracted from them remains to be seen, but just the fact that organic tissue can survive for so long is a very interesting find, and makes one wonder whether somehow, DNA too, could survive.
Some surviving soft tissue from the dino bones