End Cretaceous extinction, or the K-Pg extinction (formerly K-T extinction), occurred at the Cretaceous (Maastrichtian) - Paleogene (Danian) transition. The event was formerly called the Cretaceous-Tertiary or K-T extinction or K-T boundary; it is now officially named the Cretaceous-Paleogene (or K-Pg) extinction event.

About 17% of