Interpretation of a PhD degree in a very broad, interdisciplinary field

Question

Back when my older brother started his PhD degree I asked him what it meant to be a doctor in something other than medicine. I don't recall the exact wording he used, but the idea he portrayed was that you take a field, a narrow and specific field, and you specialise in it to a level at which when you are done, you have become one of the ultimate experts in that very specific field.

For instance if you are working with combustion physics, you might be one of the leading experts in efficient 2 cylinder, ultra-light engines made out of refined aluminium... Alternatively if you are into neuroscience you might be an expert on a particular neurotransmitter re-absorption in a particular zone of the brain following heavy exercise (or whatever, hopefully you get the point). It might be an opinionated view of a PhD but I feel it's a common way to look at a PhD degree; a certification of expertise.

Fast-forward 15 years... I am about half-way in my PhD studies in the highly interdisciplinary field of bioinformatics, where statistics, mathematical modeling, physics, molecular chemistry and programming boil together with cell biology, to top it all you typically have a theme spice, which in my case is cancer biology. I have a growing feeling that I am getting stretched thinner and thinner by the day, instead of becoming increasingly competent in a specific field, I become semi-competent in increasingly many fields.

That being the case I am not sure I (or others like myself) will fit the "definition" above. I would appreciate some perspective as to how one should be seeing highly interdisciplinary PhD studies and the development (as a scientist and a professional) that graduate studies entitles. Subsequently, how should one go about to profile him/her-self to future employers, seeing as there is no one natural field to pursue, but rather many different ones.

Answer 1

As I commented on another board just this morning, the goal of all higher education is ultimately to learn how to learn. As a PhD-level scientist, you need to be able to understand, master, and solve problems in fields which you may have never seen before you started to work in them. This means that you need to have a well-developed process for assimilating information, synthesizing it, and analyzing it. You need to be able to evaluate what is useful or not, what is correct or not, and what might work and what might not.

In an interdisciplinary field, your challenge is even harder, as you are trying to assimilate potentially disparate fields of knowledge and combine them into something more than the sum of the parts. This requires learning different jargons, different attitudes, and different approaches to problem-solving and understanding the world. This will actually be even more useful, because this means that you can be pretty good at a lot of different things—which gives you an edge over someone who's outstanding at one thing, but only one thing.

Answer 2

I completely understand your feeling. I can tell you that many other people in this field feel the same. This has nothing to do with how smart or how good they are. This issue also bugged me a lot, but I can offer some insights:

1. Bioinformatics/computational biology is really huge and you cannot be an expert in all aspects. Even if you look at senior scientists in this field, I do not think there is someone who is an expert in all subfields. You simply can't master all the physics, math, CS, chemistry and biology at an expert level - even in a much longer time than a PhD.
2. You can still have a huge impact without being a super-expert in every subfield. Just look at some of the research published in top journals. The reason is that you will have knowledge and a way of thinking that people restricted to a single field may not have. From personal experience, I can say that this is a significant advantage for asking certain types of questions and coming up with certain ideas that single-field specialists won't come up with.
3. After a while you will realize that you actually are an expert. Maybe not in the sense that you know everything about everything, but you will see that you can give good advice to other people, foresee potential problems, and so on. In addition to knowing a lot about computational biology, you will become an expert in things such as quantitative modelling, applied machine learning and "big data" analysis (I hate that term), skills which are very useful in a wide range of fields.
4. The fact that you cannot become an expert in everything doesn't mean you should neglect learning. On the contrary, you should constantly try to expand your knowledge in all related fields. And yes, it can be more difficult than learning only one subject.
5. Finally, in the end you will be working on a specific problem in a given biological problem with a given set of tools. That problem is what you really need to be an expert on.

Answer 3

In my opinion, a PhD is much more than a deep expertise in a particular field. A PhD is a certificate of the ability to do science. That's why your PhD is more broadly applicable than in your particular expertise and that's why some people can change topics dramatically after their PhD: from particle physics to atmospheric science, from space science to ornithology¹. In a German Habilitation, which is I think a step on becoming a professor, one has to write a review of a field that is not ones own.

The other day, I came accross a job advertisement from the British Met Office that had the following requirements:

· Proven ability to conduct scientific research, displaying initiative, independence and analytical skills.

· Evidence of the motivation and drive to overcome obstacles in order to solve scientific problems.

· Evidence of the ability to write software to address scientific questions.

A PhD in any natural science proves exactly that; in any case the first two points, and in many cases the third point, too. Of course, domain-specific knowledge is a plus, but it may not be a necessity. Therefore, I think you should profile yourself as a scientist.

¹^{Scientists performing stratospheric radar measurements discovered an odd diurnal pattern in their measurements near the Antarctic coast. It turns out a flock of birds was flying through the radar beam. One persons noise is another persons signal; said scientist is now cooperating in ornithological research.}

Answer 4

This may not be a complete answer, but I can empathise with you, as I am in a similar boat.

My field is an academic puree of atmospheric physics, photobiology, optics, photography, oncology, opthamology, programming and a dash of education, public information and community safety.

The steps that I take are:

• Identify the main focus/foci - this/these are the overarching main goals of your project (eg for mine, it is Atmospheric Physics and Photobiology).
• Which fields are where the applications/potential applications of your research come from? (eg for mine, they are programming, optics and community safety/education)
• Look at where you can contribute to (the remainder of the list are mine).

That last point is something my supervisor suggested I remember in times that I felt I was being academically-spaghettified - look at the disciplines not so much as fields of study, but as areas that you can and are making a contribution.

I hope this helps.