The Paleocene epoch lasted from 66 million to 56 million years ago. Modern placental mammals originated during this time. The Paleocene is a transitional point between the devastation that is the K-T extinction, and the rich jungle environment that is the Early Eocene. The Early Paleocene saw the recovery of the earth. The continents began to take their modern shape, but all the continents and the subcontinent of India were separated from each other. Afro-Eurasia was separated by the Tethys Sea, and the Americas were separated by the strait of Panama, as the isthmus had not yet formed. This epoch featured a general warming trend, with jungles eventually reaching the poles. The oceans were dominated by sharks as the large reptiles that had once predominated were extinct. Archaic mammals filled the world such as creodonts (extinct carnivores, unrelated to existing Carnivora).