From Wikipedia, the free encyclopedia. Leif Tilden (born March 20, 1964) is an American actor who played Robbie Sinclair in the sitcom Dinosaurs, and gorillas in various films including George of the Jungle, Ace Ventura: When Nature Calls and Buddy. He also wrote and directed the 2001 short bigLove and co-directed the 2001 Dogme film Reunion. He was a witness in the O. J. Simpson trial. Description above from the Wikipedia article Leif Tilden , licensed under CC-BY-SA,full list of contributors on Wikipedia.