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Natural Sciences (Biological)

The evolution of colour patterns in south american Heliconius butterflies

The 'Physical' and 'Biological' classifications in Natural Sciences are very flexible, and students often mix modules from the biological and physical sciences, or change their preferred area entirely.

St John's College has a strong history in the Natural Sciences, including among our alumni the double Nobel Prize winning geneticist Frederick Sanger and the physicist Paul Dirac, one of the founders of Quantum Mechanics. We continue these traditions today, with a strong teaching fellowship maintaining broad interests across the sciences. There are at least fifteen Fellows and other teaching staff who are directly involved in supervising Natural Scientists in the College (see 'People'). Recent research by our teaching fellows has been published in the world leading journals Nature and Science.

The Natural Sciences course at Cambridge is perhaps unique in the UK in its flexibility and broad scope. Throughout, the emphasis is on developing an understanding of principles so that graduates are well equipped to both understand and contribute to future scientific advances. The broad nature of the course is particularly well suited to modern science, where traditional subject boundaries are being abandoned in favour of cross-disciplinary approaches.

Biological study in the Peruvian AmazonThe supervision system is integral to teaching at Cambridge, and at St John's you will have regular supervisions, usually in groups of 2-3 students. In the first year you will have 4 supervisions per week, mostly with teaching Fellows from the college. The College also offers considerable additional support, including an excellent library, grants towards the costs of essential books and laptop computers, prizes for academic excellence in Natural Sciences, and of course the student led 'Larmor Society', who host guest speakers and social events throughout the year.

Many students spend the summer carrying out research projects in UK or European universities. Students in the Biological Sciences have the opportunity to take part in a research project in the Peruvian Amazon, supported by a sustainable forestry initiative 'Green Gold Forestry'. Two students per year have spent their summer in the rainforest, carrying out a research project aimed at examining the effects of low impact logging on biodiversity and forest growth. Also, students can participate in an exchange program with California Institute of Technology.

Courses in Natural Sciences

Fruit fly testesThe first year will involve choosing three (out of a possible seven) basic experimental subjects, plus an appropriate course in Mathematics. This will give you a thorough and broad foundation on which to build your chosen speciality. 

Second year students choose three subjects, giving them the opportunity to become more specialised in a particular subject, or to retain a broad approach. By the third year you will be specialising in one of sixteen subjects, chosen from a list that runs from Astrophysics to Zoology and includes Biochemistry, Chemistry, Materials Science, Plant Sciences, Psychology and Physics.

In all Natural Sciences subjects it is possible to graduate with the BA Degree after three years. Four-year courses leading to the degrees of BA and MSci are available in eight subjects including Biochemistry, Chemistry, Geological Sciences, Materials Science, Physics and Systems Biology, subject to appropriate examination performance.

Students who read Natural Sciences during their first one or two years may also complete their degrees in another subject: for example, Chemical Engineering, Mathematics, Electrical and Information Sciences, Management Studies or Law.

Biology Subject Day Lectures

Find out what to expect from Biology at St John's by playing back these lectures from our Biology Subject Days:

Watch Alex Taylor: Rewriting the Language of Life
Watch Dan Lu: How to Kill Cancer Cells
Watch Celine Glavaignon: The Role of Lipids in Parkinson's Disease

Directors of Studies

Professor Chris Jiggins - Animal Biology, Zoology & Ecology, Evolution & Behaviour, Genetics
Dr Kristian Franze - Biology of Cells
Dr Jesse Olszynko-Gryn - History and Philosophy of Science
Dr Richard Dybowski - Mathematics for Natural Sciences (Biology)
Dr Kristian Franze - Natural Sciences (Biological)
Dr Graham Ladds - Pharmacology
Dr Hugh Matthews - Physiology
Dr Uta Paszkowski - Plant Sciences


Entry Requirements

Natural Sciences (Biological): at least 2 Science subjects (which may include mathematical subjects). Minimum offer level A*A*A at A2 or equivalent.

We take a flexible approach in the subject combinations we accept but whatever the combination it must be one that gives a sufficiently firm scientific foundation for the subjects that you would wish to take in the very broad first-year course. If you are in any doubt about the suitability of your combination of subjects as a preparation for the Natural Sciences Tripos please contact us well before the deadline for submission of a formal application for advice.

We expect to admit about 30 students to read Natural Sciences every year, with approximately half classed as ‘Biological’ and half as ‘Physical’ Sciences. However, these classifications are very flexible, and students often mix modules from the biological and physical sciences, or change their preferred area entirely. Whilst we view each application independently, students invited for interview will normally have an average above 85% in three relevant subjects plus at least 90% in one AS science subject (including Mathematics). In our last round of applications, we made offers to roughly 25% of Biological applicants.

Those invited for interview will have three interviews. First a tutorial interview followed by two subject interviews by the Director of Studies and other teaching fellows. We conduct our interviews in a friendly and informal manner, and you should not feel too daunted by the prospect of them. No special preparation for the interview is necessary, or indeed desirable. The interview with the Natural Science Fellows will be concerned with subject-related topics, but we do not expect you to have detailed prior knowledge of topics outside of the areas you have covered at school. The interview is not a test of memory, but is concerned with exploring your analytical ability to think through scientific problems. Further details of the process are sent to students selected for interview.

Pre-Interview Assessment

For Biological Sciences you will be required to sit the pre-interview written assessment. More information is available here.


We take account of all of the available information about you to assess your potential and thereby to make a decision about your application. This includes reviewing your academic record, reference, personal statement, interview performances, pre-interview written assessment, and anything else that is relevant. Should you narrowly miss an offer of a place, we are very active in placing your application in the Winter Pool and in informing other Colleges who are looking in the Pool.

I’ve always been enthusiastic about Sciences in general and Biology in particular, but my time in Cambridge has certainly allowed me to confirm that studying Natural Sciences was the right decision.The Natural Science syllabus presents an ideal combination of providing a broad basis and encouraging specialisation. The first year starts with a very wide range of exciting subjects, giving you the...
'I have recently graduated, having completed the 3 year BA course in Natural Sciences. Before Cambridge I studied at a series of state schools and realised that I wanted to pursue Biology at university. I have thoroughly enjoyed my time at Cambridge, it has been rewarding academically and I also really enjoyed myself. The Natural Science course has inspired me to pursue my interest in Plant...
Dan Lu
Dan Lu studied Natural Sciences (Biological) 2007-2011, and is now studying for a PhD in Biochemistry.'I’ll be honest; coming here was a dream for me. With so many Nobel Prize winners in the sciences alone, and that’s not even including people like Newton and Darwin, the University of Cambridge is clearly a leading scientific institute. In my opinion, a huge part of this success comes down to the...
Why St John’s? 'I hadn’t completely decided what subject to apply for when the open day came around, so just signed up to the open day of a fairly central college that offered all the courses I was considering. When I got here, I fell in love immediately – the atmosphere of the college was amazing. The facilities offered by John’s (like free laundry, the gym, the JCR) are amazing, and much better...
Natalie Lawrence, Zoology, 2008-10
'I really enjoyed my time doing NatSci at John’s. The first year is quite intense in Natsci, but I got a lot of support from the College in terms of teaching and guidance. Being in a large college means that there are many other people doing the same subject, so organizing supervisions is much easier. Many supervisions are in college, because John’s has so many biology fellows. Though I did...