Horrible scientists and dinosaur fossils from New Zealand are going to ruin your day; the (mad) scientists have discovered that DNA has a half-life of 521 years. This means Jurassic Park can never happen in real life, and that means enraged, cloned Velocipedes will never terrorize Jeff Goldblum in real life.
Palaeogeneticists led by Morten Allentoft at the University of Copenhagen and Michael Bunce at Murdoch University in Perth Australia, discovered the terrible news after examining 158 DNA-containing leg bones of three species of extinct giant birds called moa, you know, like the kind in Guild Wars 2.
DNA strands break down over time as enzymes and micro-organims start to degrade the bonds between nucleotides. The set half-life of 521 years is due to groundwater, and so would apply to almost all living matter, although the actual speed of DNA decay is also determined partially by temperature. But even under optimal DNA preservation conditions, 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.
Dinosaur bones are at least 65 million years old, so no cloned dinosaurs for you, ever.