Reprinted from: Gordon, R. (1992). Physicist to biologist: A first order phase transition. Bulletin of the Canadian Society for Theoretical Biology (10), 4-5.
Most biologists have little or no training in mathematics, physics, or physical chemistry. Since they are mostly taught by biologists, this situation changes slowly. Some of the best biologists started out as physicists or physical chemists, including Louis Pasteur, Sewall Wright, Max Delbruck, and Francis Crick. Mathematicians, such as Norbert Wiener and Alan Turing, have also made substantial contributions to biology.
On rare occasions in your career you may luck out and find a biologist who will meet you half way. But if you want to make a serious foray into biology, you will probably have to become a biologist. This does not mean surrendering your thought processes so carefully honed as a physicist. On the contrary. You must maintain that intellectual integrity, that careful distinction of cause and effect, that demand for logical and numerical explanation, to be able to make a substantial contribution to biology.
As a biologist you must come to know your organism first hand. You will generally not find the data you need in the biological literature. You will probably have to get it yourself. And so you will raise bacteria, or newts, or a garden of gourds. You will come to appreciate individual variation, and perhaps put it to advantage. That small deviation from the expected occurs frequently in organisms, and hints at explanations. If you are mostly theoretically inclined, you will have to roll up your sleeves, and start your own laboratory.
You will use microscopes, microtomes, biotechnology, etc., in a critical, quantitative manner, probably designing and building new instruments en route. Thus you will bring the tools of physics to bear on your biological problems. The other side of this coin, however, is to avoid seeking a biological problem for your physical solutions.
As a newcomer with a fresh view, you must be prepared to sort through thick jargon and critically disentangle what is useful and perhaps true from vague and often wrong concepts. The best guideline here is to assume: 1) the naming of something is no substitute for understanding it; 2) the names given to things by biologists often reflect wishful thinking about our understanding of their functioning. For example, visual cortex cells in the brain called "line detectors" don't detect lines. They respond optimally to more or less linear visual stimuli, and perhaps should have been given the more neutral name "linear receptive fields". What they do for perception is not as clear as their name implies. On the other side, clear physical concepts, such as force, are rarely recognized, let alone measured, in biology.
Allow yourself at least two years to achieve a critical understanding of any biological field you enter. Remember that even the humble first year biology undergraduate student is faced with memorizing more vocabulary than a first year student of a language.
Be prepared for an immense literature, one or two orders of magnitude more verbose than what you ordinarily encounter in physics. Acquire a computer bibliography data base program and lots of second hand filing cabinets to keep yourself sane.
You should band together in societies of biophysicists or theoretical biologists or mathematical biologists, where you can effectively lobby for representation on grants councils, for fair treatment by biology editors, and for changes in biology curricula. If you want to determine for yourself how big an uphill battle this is, just examine any introductory biology text for physics or mathematics content. You probably won't find any. When you try to bring your background into your teaching to compensate, expect resistance from your biologically trained colleagues and your students. Create niches, and fill them.
Biology is on its way to joining the precise sciences, and this is an exciting time to be indulging in it. But the very personality types that enter biology must shift, and you will find it necessary to set your example and bring new kinds of minds along with you.
Don't enter biology timidly. There is no better background for it than physics, tempered with a little humility about what is achievable via, for example, physical chemistry. You'll need chutzpah: biology needs you more than it knows or will thank you for. Enter because you want to, not to please anyone else or do them a favor. You'll have trials by fire or firing squad. Your internal motivation to understand the living part of the universe is what you need to stand firm.
Finally, I'd like to add a word about history, and complexity. Organisms, from viruses on up, are undoubtedly the most complex entities in our known universe. Many biologists are overwhelmed by this complexity and intellectually are closet vitalists, in their heart not believing that life can be explained physically. You may have your doubts about the completeness of contemporary physics. But until you push it until you're up against a wall of incomprehension, you must seek explanations that grow out of what we have come to understand of the nonliving universe.
The art of entering biology is to select:
We must understand the nature of approximation and successive approximation, and be prepared to recognize when this process fails and it is time for a shift in paradigm. We now know the limitations of epicycles and Newtonian mechanics. Expect similar lessons in biology. Indeed, your greatest contributions in biology may be to change the current paradigms. Read its history, and help make it.