Mary Cover Jones was the middle child of three born to Carrie Louise Higson and Charles Blair Cover. She had a brother who was five years older than her, and a sister who was four years younger than her. Jones’ mother was a homemaker involved in several local community organizations while her father was a businessman. Due to regretting not attending post-secondary education himself, Jones encouraged his children to attend university. Visiting Chautauqua Institute on Lake Erie, Ohio became a yearly summer trip for the Cover family during Cover Jones’ childhood. After being accepted into Vassar College, Cover Jones chose to study psychology. She took every psychology course offered at Vassar College except one that was offered by Washburn. Washburn refused to admit her into the class because of a poor laboratory grade in a previous class. She pent her summer vacations, during her time in college, working with poor children in summer camps and in settlement houses.Soon after graduating from Vassar College, in 1919, Cover Jones attended a lecture by the noted behaviorist John B. Watson, in New York City. After hearing Watson’s lecture, Mary Cover Jones wondered if conditioning could be used to eliminate fears. In 1919, she began her graduate work at Columbia University and completed her Master’s degree in the summer of 1920. Mary Cover married a fellow graduate student, Harold Jones, in 1920.

In 1923, Mary Cover Jones became an Associate professor of Psychological Research at the Institute of Educational Research, Teachers’ College, Columbia University. Cover Jones conducted her famous study of Peter during her position as associate at Columbia University. After publishing the result from the Peter study in 1924, she completed a doctoral dissertation on the development of early behavior patterns in young children. She went on to work with 365 infants in various areas in New York City and studied the development of early behavior of young children. Jones did not receive attention for her work until the 1960s, when the field of behavior therapy began to coalesce under the leadership of Joseph Wolpe. In the summer of 1927, Cover Jones, her husband, and their 2 daughters moved to California. Barbara, her first daughter, was born in 1922. Leslie, her second daughter, was born three years later in 1925. She then accepted a position as research associate at the Institute for Child Welfare at Berkeley where she became involved in the longitudinal Oakland Growth Study (OGS). A position as Director of Research was offered to Harold, while Cover Jones accepted a position as research associate at the Institute for Child Welfare at the University of California, Berkeley in 1952.

In 1952, Mary Cover Jones became Assistant Professor of Education at Berkeley. Although she had relevant experience and conducted research, she was not allowed to become a full time professor due to her husband also being employed at the university. This anti-nepotism rule was very common in this era. The University of California, Berkeley eventually set aside that rule and in 1959 Cover Jones became full professor for one year. During this time her and Harold produced the first educational television course on developmental psychology  In 1960, she became president of the Division of Developmental Psychology of the APA. In the same year her husband, Harold, died of a heart attack and she retired. In 1986, Jones received the prestigious G. Stanley Hall Award from the American Psychological Association (APA). The G. Stanley Hall Award is awarded to recognize notable contributions to developmental psychology. Some of Jones’ contributions include her study of Peter which laid the foundation for behavior therapy, her development of desensitization, and direct conditioning to overcome fears. Unrelated to psychological research, Cover Jones spent her time being involved in committees related to child welfare and spent a great deal of time and effort on such causes.