The history of cancer has been given a new twist by some scientists who see the disease as a relic of our ancestors' evolution. "Cancer remains a formidable foe even 40 years after Richard Nixon officially declared war on it. A new and controversial hypothesis now offers hope that the war can ultimately be won. It suggests tumours have a limited ability to evade modern therapies—a consequence of the idea that cancer is our most distant animal ancestor, a 'living fossil' from over 600 million years ago."