The doctoral degree is granted in recognition of scholarly proficiency and distinctive achievement in a specific field of an academic discipline. The former is demonstrated by successful completion of advanced coursework (of both a didactic and an unstructured nature) and by adequate performance on the comprehensive examination. The latter consists of performing independent original research and writing a dissertation on the results of that research.

Graduate students pursuing a Ph.D. in Biology may specialize in research activities at all levels of biological organization, with emphases on ecophysiology, cellular and molecular biology, endocrinology, and ecology of aquatic organisms, or on models related to human disease.

To qualify for candidacy, students must take both written and oral comprehensive examinations. A public departmental seminar must be presented as part of the final defense of the student's dissertation. The dissertation must embody the results and analysis of an original experimental investigation.