The main objective of this study was to characterize the acceptance of evolution among biology majors. Semi-structured interviews were carried out to track the opinions of students in relation to two aspects of evolution: (1) attitudes toward evolution in general; and (2) attitudes toward human evolution. The participants characterized their acceptance of evolution for three distinct times during their university coursework: (1) at the beginning of their degree (before attending the university); (2) at the beginning of the capstone evolution course; and (3) at the end of the evolution course. Their acceptance of evolution in general changed from 31% to 79% to 98%, respectively, and their acceptance of human evolution changed from 26% to 55% to 95.2% respectively. This study investigated some of the factors that influence acceptance, such as an increased knowledge of the evidences, a religious scientist role model, and a reconciliation of scientific and religious worldviews. The results indicate that for biology majors in this study, the accumulated knowledge of the evidences of evolution over the duration of their degrees was the most influential factor.