Scientists have discovered the oldest DNA ever found: tiny fragments hidden in the dirt. The idea that soil could hold genetic traces from creatures that vanished millions of years ago seemed impossible – until one researcher had the wild idea to go and look. But how did he find DNA that most scientists thought could never survive? What forgotten worlds can this buried DNA reconstruct? And what might these revelations tell us about our own future on a rapidly changing planet?To watch the full film, visit here.Learn more about NOVA and subscribe to our YouTube channel.