44 W. D. Hamilton
W. D. Hamilton was one of the premier evolutionary theoreticians of the last century. He took a gene-oriented approach and wrote breakthrough papers on the mathematical basis for inclusive fitness, altruism, spiteful behavior, sex ratio, and sexual reproduction as a defense against parasites. Hamilton was a giant physically and academically.
I never met or corresponded with Hamilton as our academic and spatial words were had little overlap. Yet his impacts were obvious, and I learned an important lesson just watching him in action.
I saw him twice. Hamilton attended a seminar I gave at the University of Michigan in 1987. Then I saw him at a large symposium held at Cold Spring Harbor about 1991. On neither occasion did we speak.
The meeting at CSH brought together international leaders in anthropology, evolutionary biology, and linguistics. The organizers recognized that these three fields shared a common challenge: how to explain the origin of particular “traits” that appear in two or more lineages. Do shared traits (cultures, species, languages) reflect convergent (independent) evolution in each group, or sharing (or gene flow), or copying. The symposium’s goal was to compare how these three fields grappled with explaining the origin of such shared traits.
Many of the greats – including Hamilton – were there. On several occasions I watched Hamilton or other academic leaders as they listened to speakers. Hamilton was always paying rapt attention. I noted that this man was focused.
At that time, Hamilton was researching the evolutionary impacts of parasites. In the question period at the end of several talks, Hamilton asked whether interactions with parasites might influence whatever the speaker had been discussing. After a few such questions, I concluded (at least initially) that Hamilton was ‘rather focused’ on parasites.
The more I thought about his focus, I gained some insight into how he operated. Hamilton trusted his intuition that parasites were broadly relevant to life and culture. Consequently, he actively used the theme of the presenter’s talk to learn whether parasites brought novel insights inot that theme (or the reverse).
Looking back, I don’t think that Hamilton was doing this as an intentional academic exercise; rather, I think he had to determine how parasites might unexpectedly interact with other issues His act of “cross-pollination” struck me as an effective way to foster linkages between traditionally unrelated fields.
Looking back on my own career, I realize that many of my favorite projects involved integrating two different fields, that is, mixing A + B. I have been fascinated with thermal biology ever since the Kalahari, and so I tend to “see” thermal biology under every rock. I will concede that I’m in a thermal rut, but it has been a productive and fun rut. Of course, intense focus can be a black hole – I need to force myself to focus on issues other than thermal ones.
In any case, mixing fields can be fun. When I became interested in Himalayan mountaineering, I adopted statistical techniques developed in evolutionary biology to explore mountaineering ‘epidemiology’ (Chapter 46). With baby names, my interest in latitudinal variation in thermal biology of ectotherms led me to predict climatic patterns in the frequency of baby names (Chapter 59). With paleontology, I had long been fascinated with Janzen’s concept of the height of tropical mountain passes (Chapter 29) and so I naturally wondered whether and how variation in O2 levels over the Phanerozoic would limit the ability of climbers or animals to move up and over mountain barriers (Chapter 47).
In none of these cases was I forcing myself to mix A + B as an intentional exercise. That mixing happened naturally: I was fascinated with A and had to relate it to many new ideas that I encountered.
What if I were restarting my career and was searching for a primary research focus? How would I find and select a novel research theme that could entertain me for years (or even decades)? I would definitely not ask my major professor for a lead. Instead, I would consider Hamilton’s strategy. Find an established theme that has emerging merit and is also interesting to me, and then try to hybridize with other themes I meet.