Ronald Herbert Cohn (1943 – September 16, 2022) was an American zoologist who was a long-time research collaborator of psychologist Francine Patterson in her work in training Koko the gorilla in the use of American sign language. He documented much of Koko's life on film and on camera, and is credited as the illustrator for the children's books Koko's Kitten, Koko-Love!: Conversations With a Signing Gorilla, and Koko's Story. One of his photos of Koko was featured on the cover of National Geographic in 1978 and 1985.
At the University of Illinois at Urbana-Champaign, he received his bachelor's degree in 1965, his master's degree in zoology in 1967, and his Ph.D. in biology in 1971.
After receiving his PhD, Cohn worked as a cell biologist at the Stanford Departments of Medicine and Pediatrics. in 1971.