Ivan Terence Sanderson was a British biologist and writer born in Edinburgh, Scotland, who became a naturalized citizen of the United States. Sanderson wrote on nature and travel, and was a frequent guest on television talk shows and variety shows of the 1950s and '60s, displaying and discussing exotic animals.

Bernard Heuvelmans was a Belgian-French scientist, explorer, researcher, and writer probably best known, along with Scottish-American biologist Ivan T. Sanderson, as a founding figure in the pseudoscience and subculture of cryptozoology. His 1958 book On the Track of Unknown Animals is often regarded as one of the most influential cryptozoology texts.