By the late 1950s, Harry Frank Guggenheim was concerned with understanding why some charismatic leaders fought for freedom, while others sought power and domination. He believed that best-selling books on ethological approaches to animal and human behavior, especially those by playwright and screenwriter Robert Ardrey, promised a key to this dilemma, and he created a foundation that would fund research addressing problems of violence, aggression, and dominance. Under the directorship of Rutgers University professors Robin Fox and Lionel Tiger, the Harry Frank Guggenheim Foundation fostered scientific investigations into the biological basis of human nature. This essay analyzes their discussions of aggression as fundamental to the behavior of men in groups in order to elucidate the private and professional dimensions of masculine networks of US philanthropic and academic authority in the late 1960s and 1970s.