THE AUTHOR 
Dr. Calhoun is a member of the Laboratory of Psychology of the National Institute 
of Mental Health, National Institutes of Health, U.S. Public Health Service, Be- 
thesda, Md. This report is based upon a study conducted under the auspices of 
the Johns Hopkins University School of Hygiene and Public Health. Analysis of 
the data and preparation of this report were made possible by facilities made available 
by the Walter Reed Army Medical Center and the National Institutes of Health. 
Dr. Calhoun’s basic training is in ecology. Since 1949 his close association with 
psychologists, psychiatrists and sociologists has led him to orient his studies to provide 
insights relevant to concepts and problems in these disciplines. This report and these 
associations led to more precise experimental studies of social behavior among ani- 
mals. The general conclusions of these studies, conducted at the National Institutes 
of Health between 1955 and 1962, are presented in reference { 91 ) and in the February 
1962 issue of Scientific American. 
Public Health Service Publication No. 1008 
IX 
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