Voices heard in the program:
DR. EDWARD B. DAESCHLER is Curator of Vertebrate Zoology and Paleontology at The Academy of Natural Sciences.
KENT ULLBERG is an artist and curator of natural history. The sculptor of "Deinonychus," he was born in Sweden and has lived in the United States since 1974.
DR. LEONARD WARREN (1925-2019) is the author of the biography "Joseph Leidy: The Last Man Who Knew Everything." Dr. Warren was a Professor at the Wistar Institute of Anatomy and Biology and at the University of Pennsylvania.
Segment Producer: Jonathan Menjivar