(CNN) The science behind the Jurassic Park films always seemed far-fetched, even before the latest instalment, Jurassic World, introduced the idea of genetically engineered super-dinosaurs.
For one thing, finding mosquitoes that had drunk the blood of dinosaurs and then been preserved in amber for hundreds of millions of years is incredibly unlikely. But there's another more important reason: proteins such as DNA degrade fast after a creature's death. They are almost never found preserved in bones older than a few thousand years. This has been the dogma for many years.