Robert Mearns Yerkes (1876-1956) was an American psychologist, primatologist, and ethologist who made significant contributions to the field of behavioral science. He is best known for his research on animal intelligence and behavior, which he conducted in the early 20th century. His work helped to shape the emerging field of comparative psychology, which focused on understanding the behavior of different species of animals. Yerkes was also a pioneer in the study of animal learning and social intelligence, and his research greatly influenced later research in the field.
Yerkes was born in Pennsylvania in 1876 and attended Swarthmore College, where he earned a bachelor’s degree in 1898. He then studied medicine at Johns Hopkins University, where he received his medical degree in 1901. After graduating, he took a job as an assistant professor of psychology at Harvard University, where he remained for the rest of his career.
At Harvard, Yerkes conducted a series of experiments to study animal behavior, which he published in his book, The Mental Life of Monkeys and Apes (1908). In this book, Yerkes proposed that intelligence could be measured in animals and that certain species of animals, such as chimpanzees, were capable of complex thinking. He also argued that animal intelligence was related to their environment, and that intelligence could be improved with proper training.
Yerkes continued his research into animal intelligence and behavior in the 1920s and 1930s, when he conducted a series of experiments on learning in chimpanzees. He found that chimpanzees could be taught to solve simple problems, such as finding hidden objects or pressing levers to get food. He also found that chimpanzees had a sense of social intelligence, and that they could remember the past and anticipate the future.
In addition to his research on animal intelligence, Yerkes also conducted research into human behavior. He published a book, Human Intelligence (1917), in which he proposed a theory of intelligence based on the concept of mental age. He argued that intelligence was not fixed but could be improved with proper education and training.
Yerkes’ work on animal and human behavior had a lasting impact in the field of psychology. His research helped to shape the emerging field of comparative psychology, and his work on animal learning and social intelligence influenced later research in the field. Yerkes’ legacy is still seen today in the research of animal behavior and intelligence.
References
Falk, J. (2017). Robert Mearns Yerkes (1876–1956): Pioneering Psychologist, Primatologist, and Ethologist. Perspectives on Psychological Science, 12(5), 830-834.
Gould, J. (2013). The Mismeasure of Man (Revised ed.). New York, NY: WW Norton & Company.
Gustafson, G. (1977). Robert Mearns Yerkes: 1876-1956. American Psychologist, 32(2), 97-99.
Yerkes, R. M. (1908). The Mental Life of Monkeys and Apes (Vol. 1). Chicago, IL: University of Chicago Press.
Yerkes, R. M. (1917). Human Intelligence. New York, NY: MacMillan.