Ivan T. Sanderson (1911-1973) was a British born naturalist who conducted a number of expeditions into tropical areas in the 1930s. Having become an American resident, he became interested in sightings of the Yeti and other such apocryphal humanoids, as well as in reports of extraterrestrial visitors.

During the 1950s and 1960s he was widely published in such journals of popular adventure as True, Sports Afield, and Argosy.

He was the author of several accounts of his naturalist expeditions; Caribbean Treasure, and Animal Treasure are hard-to-obtain classics of travel literature.

Sanderson was married twice and died of cancer in the United States.