Horizon - 2002-2003 - Revisited: Dawn of the Dinosaurs

An investigation into the theory that a massive comet impact in the Gulf of Mexico was responsible for the mass extinction of dinosaurs and other flora and fauna 65 million years ago. This is followed by an updated look at the role played by asteroid collisions in evolution, as evidence emerges to suggest that it was precisely such an impact which brought about their existence in the first place.