after secondary education at gordon bell high school, bowman studied medicine at the university of manitoba medical college with m.d. in 1949. after serving his medical internship at winnipeg general hospital, he spent two years in rural general practice in oakville, manitoba. he then trained as a pediatrician at the children's hospital of winnipeg, at the winnipeg general hospital’s newborn service and rh laboratory, and at the babies hospital of columbia presbyterian medical center. he became a certified pediatrician in 1956 and then from 1956 to 1957 studied and lectured in clinical pediatrics at queen’s university in kingston, ontario. in 1957 he joined his identical twin brother william david "bill" bowman (1925–2011) in the pediatric department of the manitoba medical clinic. in 1957 j. m. bowman began working as a part-time associate with bruce chown and marion lewis at winnipeg's rh laboratory and as a part-time member of the university of manitoba's pediatric department.