In Prehistoric ParkEdit
Thylacoleo was one of the animals Nigel was considering bringing back to Prehistoric Park. Though he (incorrectly) refers to it as a cat, it was actually a marsupial and unrelated to cats (the name 'marsupial lion' is a reference to the animal's lifestyle as a large predator, and not any indication of a relationship to lions).
According to Nigel, the Thylacoleo was an excellent climber, and it would climb into trees and wait for prey to come near then proceeding to leap down on its victim. Being a marsupial, the Thylacoleo young grew in a pouch like other marsupials such as the kangaroos and Tasmanian devil.
However, Nigel eventually decided to bring back a Smilodon instead of a Thylacoleo.