Smilodon fatalis, Illinois' sabre cat, was the top North American predator during the later part of the Ice Age. Although much like modern lions, they were more heavily muscled and were somewhat shorter. They had massive strength and could knock down a seven foot sloth or take down a young bison, slashing the soft neck or underbelly causing the animal to bleed to death. Smilodon was a skillful ambush hunter, springing from the cover of bushes, trees or rocks, sometimes in pairs or even groups. They were social animals living in prides, caring for young, old, sick and wounded. Sabre cats were never abundant. In Illinois, they probably lived in the central and southern parts. Their fossils have been discovered over much of North America, thousands from the tar pits of California, representing more than 1,200 individuals. Smilodon is not closely related to modern cats. Modern cats belong to subfamily Felidae, which includes lions, tigers, leopards and jaguars. Sabre cats belong to subfamily Machailurini, which includes the dirk-toothed cats.