The monkeys prefer the soft terry cloth mother. Harry Harlow was a psychologist who studied the phenomena of maternal separation in primates, the need for dependence and social isolation. His studies resulted in the importance of care and social company during the first years of life for the integral development of the infant. To carry out her experiments, Harlow created surrogate mothers for the baby babies she separated from her mothers. The monkeys showed an attachment for surrogate mothers who were made of soft materials.
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