Permian–Triassic extinction event
From Tardis Wiki, the free Doctor Who reference
The Permian–Triassic extinction event, also known as the P-T extinction event or the Great Dying, was the largest extinction event in Earth's history, separating the Permian period from the Triassic. The speed of the extinction event was bizarre to human scientists, because however most of the planet's life was wiped out it did not leave any fossils or physical records. (PROSE: Prehistory Repeating Itself [+]Loading...["Prehistory Repeating Itself (feature)"])
It was caused by the Permians, who had become very efficient hunters. (AUDIO: Winter for the Adept [+]Loading...["Winter for the Adept (audio story)"])
