Degree Programs

Biology, Organismic and Evolutionary

Harvard University offers graduate instruction in several areas of biology. The members of the Department of Organismic and Evolutionary Biology (OEB) share a common interest in understanding the structure, function, and variation of biological systems.

The research interests of the OEB faculty include the flow of energy and material through ecosystems, the development and structure of communities and populations, the diversity of plant, animal, and microbial groups, and the mechanisms that have permitted diversity to evolve. These studies span a wide range of spatial and temporal scales and include many different levels of biological organization.

A variety of theoretical, descriptive, and experimental approaches are used in the laboratory and field studies carried out by members of OEB. We have representation in anatomy, behavior, biogeochemistry, development, functional morphology, physiology, paleontology, population genetics, molecular evolution, systematics, and the biology of global change.

The Harvard University Herbaria and the Museum of Comparative Zoology (MCZ) house essential libraries, extensive natural history collections, and experimental laboratories that are utilized by faculty and students of the department. Other resources include the Concord Field Station of the MCZ, the Harvard Forest, and the Arnold Arboretum.


Students considering graduate work should request the GSAS Guide to Admission and Financial Aid from:

Office of Admissions and Financial Aid
Harvard Graduate School of Arts and Sciences
Richard A. and Susan F. Smith Campus Center 350
1350 Massachusetts Ave
Cambridge, MA 02138

We encourage online submission of the application.

Completed applications should be received by December 2 in order to be considered for admission for the coming year.

Although Harvard University awards both the AM and the PhD degrees in biology, the department will recommend for admission only candidates for the PhD degree.

Applicants should have the equivalent of seven full (two-term) courses in the fields of biology, chemistry, physics, mathematics, computer science, or geology; at least a third must be intermediate-level courses. GRE General scores are required. GRE subject scores are recommended. Foreign students should have first class honor degrees, recent TOEFL scores of at least 550, or hold a degree from an institution at which English is the language of instruction.

Financial Aid

The department has available financial support based both on merit and need. Ordinarily, students who are accepted into the program receive substantial financial aid. Stipends are typically composed of scholarships, teaching fellowships, and research assistantships. Ordinarily, the department does not provide scholarship or fellowship support beyond a period of six years.

Applicants are expected to seek fellowship support from sources outside the University. US citizens who have received fewer than 30 graduate-level credits are expected to apply for pre-doctoral fellowship opportunities provided by the National Science Foundation (NSF). Applications for NSF fellowships are typically due in the fall, and applicants may find application materials at

Doctor of Philosophy (PhD)

A departmental Graduate Committee is responsible for all matters pertaining to OEB graduate students. It considers applicants for admission and approves all examination committees appointed for doctoral candidates.

Course selection (other than those prescribed; see Prescriptions) is determined by consultation between the advisor and student. During the first two years, satisfactory progress towards the degree requires fulfillment of the departmental teaching requirement, successful completion of at least 16 half-courses (with no more than 12 of these half-courses at the 300 level), completion of all prescribed courses with a grade of B- or better, and passing the qualifying examination (which should be held no later than the end of the second year). Thereafter, satisfactory progress is assessed by the student’s Dissertation Committee at an annual Dissertation Conference.

Academic Residence Requirements: A minimum of two years of full-time study is required to fulfill the residence requirements (16 half-courses passed with distinction). Research (300) courses taken under the direction of members of the Harvard faculty count toward fulfilling the academic requirements. These courses ordinarily require a minimum of ten hours per week (one-quarter TIME) for a minimum of a term. Full-time research (recognized as TIME by the Registrar) will generally not be accepted by the department as part of the academic requirement for a degree.

Research Advisor: Upon admission students will be assigned a faculty member in the department to serve as a dissertation research advisor. Students are encouraged to consult freely with any staff member on matters pertaining to their programs and may change to another advisor at any time, subject to the approval of the new advisor and the chair of the Graduate Committee and notification of the department office.

Students must have an advisor at all times and it is the student’s responsibility to ensure this. Any student who does not have an advisor at the beginning of a term must withdraw from the department at the end of that term if arrangements for a new advisor have not been made by that time.

Prescriptions: OEB has relatively few requirements, generally designed to ensure that entering students have a broad background. They include: 1) college-level calculus; 2) statistics; 3) a reasonable combination of courses in cell biology, molecular biology, and genetics; and 4) courses on the biology (including lab work) of at least two kingdoms. If deficiencies in a applicant’s academic background warrant, courses may be prescribed by the Graduate Committee, and these will be identified at the time of the offer of admission. These courses may be completed prior to matriculation into the program, but they must be completed with a grade of B- or better prior to the student’s qualifying examination. Additionally, the Graduate Committee will determine from each student’s prior training and in discussion with the student and the advisor, an appropriate individual course of study to be completed by the qualifying exam. Each student will complete an orientation seminar program offered by various faculty in the department.

Teaching Requirement: The department requires each PhD candidate to participate in teaching for two terms at a minimum of onequarter TIME each term. The first of these is ordinarily fulfilled during the second year, and the second requirement is ordinarily fulfilled during the fourth year. Teaching in the first year is not allowed. Teaching more than 2 semesters during years one to four can be done depending on the department's need for teaching fellows. During the fifth and sixth year, departmental funding comes in the form of teaching fellowships.  Unless a student has external funding sources, he/she will be required to teach both in the fall and spring semesters.

Admission to Candidacy for the PhD Degree: After completion of 16 graded half-courses in biology and related subjects (300 level courses are included), the student’s record is reviewed by the Graduate Committee. Favorable action will provisionally admit the student to candidacy for the PhD degree. Final admission to candidacy is by means of the qualifying examination.

Qualifying Examination: This is an oral examination which shall be taken before the end of the second year of graduate study. Prescriptions must be satisfied prior to the examination. The Graduate Committee will review any petitions for exception.

The examination committee will consist of the student’s advisor acting as chair, plus three additional individuals. At least two of the additional members must be members of the OEB faculty. Two of the examination committee members will be designated by the advisor, and the fourth member will be appointed by the chair of the Graduate Committee after consultation with the advisor. The overall composition of the examination committee must be approved by the chair of the Director of Graduate Study.

By the end of the fall term final exams of the student’s second year, the student, after consultation with his or her advisor, will submit to the Director of Graduate Studies and to the OEB departmental office a list of three broad and non-overlapping topics on which to be examined and the time and location of the examination. The topics should be pertinent to, but not be restricted to, the specific topic of the proposed or ongoing dissertation studies.

At least two weeks prior to the exam, students should present to the examination committee a dissertation proposal, plus a syllabus outline for three potential courses that could be taught corresponding to the three topic areas. During the qualifying examination, the student’s knowledge of at least two of the three chosen topics will be appraised. In addition to this evaluation, the examination committee will determine whether the student has satisfactorily completed the prescribed studies decided upon earlier by the Prescription Committee.

If the qualifying examination reveals serious deficiencies, the committee may require 1) that the student be reexamined at a later date, or 2) that the student not be admitted to candidacy for the doctoral degree.

Dissertation Conference: In the dissertation conference, students have a relatively early opportunity to review with their advisor and the Dissertation Committee the dissertation project, its progress, and future potential. The dissertation conference should be held annually, with the first conference taking place in April of the student’s third year. The student should arrange the conference in March of the fourth year of study, and then in the month of February for all subsequent years. One month prior to the conference, a one-page abstract of proposed and/or completed work and the time and location of the conference should be submitted to the OEB departmental office. The student should present in person a brief account of the results obtained and plans for additional research. The committee should indicate to the student whether it anticipates that the dissertation will be acceptable, and should also suggest improvement where needed.

The Dissertation Committee will consist of the student’s advisor, who will serve as chair, and two other members suggested by the advisor and approved by the chair of the Graduate Committee. At least three members of the committee must be members of the Department of Organismic and Evolutionary Biology.

Dissertation: The dissertation is written under the supervision of the student’s research advisor and will be read by members of the Dissertation Committee. Prior to the dissertation examination, the candidate will prepare a summary of the dissertation for distribution to the members of the committee. The final copies of the dissertation should conform to the standards outlined in The Form of the PhD Dissertation.

Public Presentation of Dissertation Research: All PhD degree candidates in OEB are required to present the subject matter of their dissertations in a seminar open to the general biological public within the University, and to which the members of the Dissertation Examination Committee and OEB faculty have been invited. This presentation shall take place sometime following the dissertation conference and prior to the dissertation examination.

Dissertation Examination: The dissertation examination, conducted orally, is usually held at least one month before the date on which degrees are to be conferred. Final dates for holding dissertation examinations are announced early in each academic term. At least two weeks before the date set for the public presentation/examination, the candidate will present the dissertation committee with at least two copies of the dissertation in final form (but not yet bound), and make available a third copy in the OEB office for review by other members of the faculty. After the dissertation examination has been held, the committee may decide that the candidate passes, fails, or passes on condition that specific changes be made in the dissertation.

Master of Arts (AM)

The Department of Organismic and Evolutionary Biology does not admit students whose sole purpose is to study for the master of arts degree. However, graduate students admitted to the any PhD program at Harvard University may apply for the AM degree if they fulfill the following requirements:

  1. Six graded half-courses in the Department (or approved by the Director of Graduate Studies), with no grades lower than B- and an overall grade average of B or better.
  2. At least three of the six courses must be below the 200 level.
  3. At least two of the six courses must be at the 200 level.
  4. TIME and 300-level courses will not ordinarily be accepted toward the AM degree.
  5. AM candidates must submit a written paper based on original research conducted under the guidance of a faculty member in the department.

Participating Faculty