After serving 2 years in the Korean War, earning the Combat Medical Badge, he returned to the United States, married in 1954, and completed a PhD in psychology from Vanderbilt University in 1958.

[1] In July 1966, while working with John A. Morrison for the NIH Laboratory of Perinatal Physiology in Puerto Rico, they performed an experiment in the adaptation of rhesus monkeys to a new environment.

His most famous studies involved experiments in which he would take a single individual in the group out into the forest and show them the location of food or other type of stimulus.

This work laid the foundation for his seminal papers on cognitive mapping and the representation of space[4][5] Another set of landmark studies by Emil Menzel involved his descriptions of cooperative tool use in captive chimpanzees.

The escapes almost always occurred after the researchers and care staff had left for the day, suggesting that the apes were inhibiting their behavior until circumstances were ripe for a break out.

[1] Though a naturalist and ethologist at heart, Emil Menzel did not sit idly as technology improved and allowed for alternative ways of testing chimpanzee cognition.

Before testing, the students had to create a faithful pictorial representation of all the potential landmarks and features in the outside enclosure so that they could precisely determine their travel and foraging patterns.

[13][14] This article incorporates text from a scholarly publication published under a copyright license that allows anyone to reuse, revise, remix and redistribute the materials in any form for any purpose: Hopkins W.D., Washburn D.A.