Animal testing on non-human primates between the monkeys natural behaviors versus the behaviors expressed by the diazepam induced monkeys in thirteen different locations inside the maze. Scientist Barros and his colleagues created this model to allow the monkeys to roam a less confined environment and slightly eliminate outside factors that may induce stress. Many of the best-known allegations of abuse made by animal protection or animal rights groups against animal-testing facilities involve NHPs. The so-called "pit of despair" was used in experiments conducted on rhesus macaque monkeys during the 1970s by American comparative psychologist Harry Harlow at the University of Wisconsin–Madison.<ref name="Blum1994/95">Blum, Deborah. "The Monkey
Rhesus macaque Jean-Baptiste Audebert, who applied the name to the species, stated: "it has no meaning". According to Zimmermann’s first description of 1780, the rhesus macaque is distributed in eastern Afghanistan, Bangladesh, Bhutan, as far east as the Brahmaputra Valley in peninsular India, Nepal, and northern Pakistan. Today, this is known as the Indian rhesus macaque "M. m. mulatta", which includes the morphologically similar "M. rhesus villosus", described by True in 1894, from Kashmir, and "M. m. mcmahoni", described by Pocock in 1932 from Kootai, Pakistan. Several Chinese subspecies of rhesus macaques were described between 1867 and 1917. The molecular differences identified