Harlows Monkey

Harry Harlow was an American psychologist who investigated whether infants bond with their mother because of cupboard love (i.e. the fact that their mother provides them with food) or, as Bowlby suggested, an inbuilt tendency to become attached to stimuli that possess certain properties (such as being warm and soft to the touch). The problem is that, under normal circumstances, mothers simultaneously provide food and tactile comfort for their babies. An observational study alone could not separate out the influence of these two factors. To test it experimentally, one group of mothers would have to be prevented from feeding their babies, while another group would have to be prevented from holding and cuddling them. Although, for reasons of ethics, such an experiment is impossible with humans, he could conduct it with monkeys.
Some of the most influential work on attachment was conducted by Harlow on a group of rhesus macaques (Macaca mulatta), a mediumsized monkey with light brown fur and a pink face. In the wild, they are found throughout mainland Asia. They are reasonably easy to keep and breed in captivity and are often used in research.
It is interesting that Harlow came to study attachment in rhesus monkeys almost by accident. He had hoped to study intelligence in rats, but when he took up employment at the University of Wisconsin he discovered, to his great consternation, that the rat laboratory had been dismantled. However, when he started observing monkeys at the local zoo, he quickly realised that their intellectual abilities outstripped those of rats. Harlow secured funding for a primate laboratory at the university and set out to study intelligence in monkeys.
One of the problems with the wild-caught monkeys that were used in the laboratory was that they often carried disease. As a result the baby monkeys were separated from their mothers and housed in separate cages on their own. During daily cage cleaning Harlow noticed that the babies would protest