Abstract
Brian Charlesworth is a Senior Honorary Professorial Fellow at the University of Edinburgh. His work has involved the application of population genetics to a variety of issues in evolutionary biology. His current research is on population genetics theory, molecular evolution and genome evolution. He has published over 300 papers and three books.
Interview with Brian Charlesworth, who studies evolutionary genetics at the University of Edinburgh.
What turned you on to biology in the first place? From an early age I was fascinated by living creatures, especially animals. My early childhood home was in Hove, where I enjoyed collecting snails from a bombsite and marine animals from rock pools, as well as going on walks in the nearby Sussex countryside.
Who were your key early influences? As a child I read a lot of natural history books and especially loved the ones about the Lake District by ‘Romany’, who I suppose is almost totally forgotten now. Gerald Durrell was also one of my favourites (he still is). I had excellent biology teachers at my high school and got into studying genetics and evolution in my teens — I guess I’ve never really grown up.
As a teenager and undergraduate I read the classic books on evolution by Dobzhansky, Fisher, Haldane, Maynard Smith, Rensch and Simpson, not that I really understood a lot of their contents. However, their writings stimulated me to take genetics for my final year at Cambridge and embark on a PhD in population genetics.
My postdoctoral advisor at Chicago, Richard Lewontin, was a huge influence on me: he was at the peak of his career with a group of very clever young people around him, several of whom became leading figures. His ability to ask critical questions and not tolerate bullshit, as well as do first-class science, was a real inspiration to me and my fellow postdocs. I was also fortunate to later work under Philip Sheppard and John Maynard Smith, both outstanding scientists in very different ways. I think that learning by example from really good people is very important for young scientists.
And what drew you to your specific field of research? Genetics attracted me because of its strong theoretical and quantitative content, combined with the rigorous testing of hypotheses against experiment and observation. An awful lot of biology, both ancient and modern, is tantamount to stamp collecting (to misquote Rutherford). I got into population genetics because of my interest in evolution and because I was attracted to the application of mathematical models to biological issues, although I am not especially good at maths. The application of molecular biology to evolution and population genetics was just starting when I was a PhD student, and the whole field has simply exploded over the past 50 years, so it was a lucky choice.
Do you have a scientific hero? You’d have to be an idiot not to name Charles Darwin as a hero if you are interested in evolution — his originality and profundity are amazing, and his intellectual legacy pervades evolutionary biology. After Darwin, the ‘Founding Fathers’ of population genetics, Fisher, Wright and Haldane, are my scientific heroes. Fisher was probably the greatest evolutionary thinker since Darwin, with an extraordinary combination of biological insight and mathematical virtuosity — but Haldane and Wright ran him pretty close.
Do you have a favourite paper or science book? Darwin’s On the Origin of Species is the best book on biology ever written: its English style is superb (greatly admired by Lytton Strachey, who was no slouch), the marshalling of facts to test the ideas is unsurpassed, it revolutionised our ideas about the position of humans in the natural world and it can be understood by any intelligent reader. My favourite paper is R.A. Fisher’s 1922 paper ‘On the dominance ratio’. This introduced all the basic theoretical content of population genetics, including selection at a single locus and the stochastic effects of finite population size. Everything we do in population genetics today flows from this paper.
What’s your favourite experiment? Mendel’s crossing experiments on peas. These were the first experiments on heredity where a clear hypothesis was tested against quantitative data obtained from a careful experimental design. All of genetics comes from Mendel’s ideas and results. I am particularly fond of Mendel because my father attended high school in Brno (he was a refugee from the Nazis).
What is your favourite conference? My favourite conference is the annual Population Genetics Group Meeting, which was founded over 50 years ago by the late Bryan Clarke. It is open to anyone who wants to attend, contributed talks and posters are assigned on a first-come, first-served basis regardless of academic status (old codgers like me get a look-in), there is no formal organisation (each year someone volunteers their university as a host) and the scientific quality is just as high as that at more prestigious meetings. It is also a lot of fun, with plenty of opportunities for people to get together, talk, eat and drink.
What has been your biggest mistake? As a postdoc in 1970 I analysed a model of selection in a density-dependent population. I found that sufficiently strong density dependence could result in limit cycles of population size. If I had pushed it a bit further, I might have discovered chaos, which made Robert May famous a few years later. One consolation is that John Maynard Smith made the same mistake.
What is your greatest research ambition? I think that I am being fairly honest in saying that I’ve never really had any clear ambitions, other than not to starve or become homeless. I take up a problem, work on it until I either solve it or abandon it and then go on to the next one. I like to understand things by either finding them out for myself or studying what others (mostly much more gifted than myself) have discovered. I find the question that often gets asked at job interviews “where do you see yourself in X years’ time” quite annoying; the whole point of research is that you don’t know what (if anything) you are going to discover in a year or so’s time.
Do you feel a push towards more applied science? I think that funding agencies are under a lot of pressure from governments and businesses to push people towards doing more applied work. This is misguided because good scientists are primarily motivated by curiosity about how the world works; a lot of applied science research is quite dull and leads nowhere. In addition, advances in pure science have unpredictable applications. For instance, genetic counselling and the identification of human disease genes by GWAS would not be possible without the basic understanding of genetics that originated with Mendel and Morgan, who worked on model organisms rather than humans. Scientists usually have better ideas about what’s important than ministers, civil servants and businesspeople. Business in the UK is notorious for its emphasis on short-term profits and failure to follow up on scientific innovations.
Which aspect of science, your field or in general, do you wish the general public knew more about? I think that the general ignorance about basic probability and statistics has been vividly brought out by the current coronavirus epidemic. A major issue is that people in government and media are nearly all devoid of any scientific education and often seem actively proud of their inability to understand quantitative data and the associated uncertainties. We need to do far more to inform school students about these matters. Unfortunately, the government seems to want schools to drill, rather than educate, children.