Marine Biology (BS)

Students aboard RV Sproul review specimens during a deep-sea biology field course.
Students examine specimens aboard research vessel Robert Gordon Sproul during a field trip for a deep-sea biology course.

Undergraduates in marine biology will develop an understanding of the biology of marine organisms and the biological and physical processes that affect these organisms, their populations, and their coastal and oceanic ecosystems. The major requires a foundation in the natural sciences, a rigorous core of marine biology courses, and a unifying laboratory/field course that engages students more directly in the discovery process and in analyzing and interpreting data.

Majors select electives from a growing set of upper division Scripps Institution of Oceanography (SIO) courses in marine biology and related disciplines. The marine biology curriculum takes advantage of the UC San Diego's unique physical location along the Pacific Ocean. Laboratory work and field trips to intertidal zones, salt marshes, and other marine ecosystems are important components of the instructional program.

Ocean sciences are relevant to many contemporary environmental issues and problems and central to understanding earth-system evolution, dynamics, climate and sustainability. A major in marine biology is an appropriate start for students who are seeking a career or graduate studies in marine biology and related biological disciplines, a career in fields such as marine conservation, or simply interested in the major to broaden their base of knowledge and experience in the biological sciences.

Program advisors and faculty can provide additional information on career and graduate school opportunities. It is strongly recommended that all Marine Biology majors meet regularly with academic advising staff in the Scripps Institution of Oceanography Undergraduate Education Office in Galbraith Hall and with the marine biology faculty advisor to discuss and update curriculum choices.

For information on applying to UC San Diego and SIO Transfer Major Preparation see our How to Apply page. Exceptional students in the Marine Biology major with an interest in research are encouraged to consider the Scripps Undergraduate Honors Program. Please note that all academic advising questions (for current students) are handled via the Virtual Advisor.


Marine Biology (BS)
Degree Requirements 

Students must receive a grade of C- or higher in any course to be counted toward fulfillment of the major requirements (with the exception of SIO90 and SIO139 which are only offered on a P/NP basis). 

Lower Division Requirements

Upper Division Requirements

  1. Marine Biology Core: (all courses required)
    • SIO 132: Introduction to Marine Biology
    • SIO 134: Introduction to Biological Oceanography
    • SIO 181: Marine Biochemistry
    • SIO 136: Marine Biology Laboratory
    • SIO 139: Current Research in Marine Biology Colloquium
  2. Biology Core Courses: (all courses required)
  3. Ocean Physics and Chemistry Requirement
    • SIO 119: Physics and Chemistry of the Oceans
  4. Restricted Electives (at least 5 of the following; 2 must be indicated as laboratory courses):
    • SIO 101: California Coastal Oceanography (Lab)
    • SIO 104: Paleobiology & History of Life (Lab)
    • SIO 121: Biology of the Cryosphere
    • SIO 122: Ecological Developmental Biology
    • SIO 123: Microbial Environmental Systems Biology
    • SIO 124: Marine Natural Products
    • SIO 125: Biomechanics of Marine Life
    • SIO 126: Marine Microbiology
    • SIO 127: Marine Molecular Ecology
    • SIO 128: Microbial Life in Extreme Environments
    • SIO 129: Marine Chemical Ecology
    • SIO 131: Parasitology (Lab)
    • SIO 133: Marine Mammal Biology
    • SIO 137: Ecosystems & Fisheries
    • SIO 138: The Coral Reef Environment
    • SIO 145: Introduction to Field Methods in Biological Oceanography (Lab)
    • SIO 146: Methods in Cell and Developmental Biology of Marine Organisms (Lab)
    • SIO 147: Applications of Phylogenetics (Lab)
    • SIO 183: Phycology: Biology of Marine Plants (Lab)
    • SIO 184: Marine Invertebrates (Lab)
    • SIO 185: Marine Microbiology Lab (Lab)
    • SIO 186: Microbiomes Across Environments (Lab)
    • SIO 188: Biology of Fishes (Lab)
    • SIO 189: Pollution, Environment and Health
    • BIBC 102: Metabolic Biochemistry
    • BIBC 103: Biochemical Techniques Lab (Lab)
    • BIEB 102: Introduction to Ecology
    • BIEB 150: Evolution
    • SIO 199: Independent Study for Undergraduates

SIO 199 Information for Marine Biology Majors:

All Marine Biology Majors interested in enrolling in SIO 199 must also complete the SIO 199 Supplemental Application for Marine Biology Majors.  This supplemental document has sections that must be completed by both the student applicant AND the proposed faculty advisor.  Student must submit their completed Supplemental Application as a PDF attachment to the online SIO 199 EASY Application.  Incomplete or missing Supplemental Applications will result in your SIO 199 application being denied.

Instructions for enrolling in SIO 199 via the Enrollment Authorization System (EASY) can be found here.

SIO 199’s (and other 199 experiences) do NOT automatically apply as Electives in the Marine Biology major.  The SIO Department must review and approve (by student petition only) all independent student research projects for major credit.  Students must also have previously indicated on their Supplemental Application what type of major credit (if any) they intend on requesting. Students may enroll in SIO 199 multiple times, however, only one SIO 199 may be applied to a student's major.

Students interested in the possibility of using a 199 to meet a lab elective requirement should discuss the process with a department advisor before initiating a 199 application.