Countless childhood dreams dissolved today upon the news that the calculated half-life of DNA figures out to around 521 years, all but invalidating the chances of a real-life "Jurassic Park."
The DNA fact-finding project involved a team of palaeogeneticists testing 158 leg bones belonging to three species of extinct giant moa birds ranging from 600 to 8,000 years old.
After running a series of comparisons between the age of the various bones and DNA degradation within each specimen, the researchers estimated that DNA's half-life works out to about 521 years after being kept in a swamp with an average temperature of 13.1 Celsius (55 Fahrenheit). Even a more ideal preservation temperature of minus 5 Celsius (23 Fahrenheit) would only result in readable DNA from specimens up to 1.5 million years old, meaning there is no possible way we can see a 65-million-year-old T-Rex waving its tiny arms about in this time frame.
DNA breaks down for a variety of reasons, including degradation from external influences such as temperature, water, soil chemistry, and so on. After half a millennium, the researchers assume that DNA continues to degrade as the nucleotide bonds within break in half. Each 521-year segment serves as another chapter of nucleotide structure breakdown and carries on until the bonds no longer exist. However, science has yet to determine the breakdown speed of DNA in environments that are more supportive of preservation, such as permafrost.
Morten Allentoft at the University of Copenhagen and Michael Bunce at Murdoch University in Perth, Australia, worked with a large team on the findings, which were published today in the Proceedings of the Royal Society B science journal.