Anecdotally, many great scientists had their best ideas when young. For instance, in ecology, G. F. Gause wrote his classic The Struggle For Existence when he was an undergraduate (!) See this post and comments for some other “prodigies” in ecology and evolution. But also anecdotally, there are scientists who did tremendously important work late in their careers. Anecdotes about exceptional people are, well, exceptional. When does the typical researcher peak?
We now have an answer from economics (ht Marginal Revolution). According to the linked paper*, academic economists who obtain tenure exhibit peak productivity at the time they’re tenured, with productivity falling 25-30% in the next five years and declining steadily for a decade thereafter. That’s true whether productivity is measured as number of publications, or as proportion of publications that become highly cited. Conversely, the proportion of publications that end up being poorly cited rises steadily after tenure, while the proportion that end up being highly cited declines. And this does seem to be connected to tenure per se, as the authors show by exploiting among-economist variation in the timing of tenure.
I’m now very curious whether the same would be true in ecology. I’m not really sure–what do you think?
These data make me feel even better about my goal to be the Jamie Moyer of science, since apparently that would be a major accomplishment if I somehow managed it. 🙂 And I’m now even more impressed with scientists who’ve done outstanding work late in their careers.
So why do researchers peak around the time they get tenure? The authors speculate that obtaining tenure induces academics to rest on their laurels rather than taking intellectual risks. I think that’s only one of many non-mutually-exclusive explanations, and doubt it’s the main explanation in most cases. For instance, post-tenure academics have more administrative and service duties, leaving them both less time to write and less time to read and think. As Peter Adler has noted, it doesn’t get any easier after you get tenure–it gets harder. I suspect that the rate at which one comes up with good ideas post-tenure is limited much less by inclination to work hard and take intellectual risks and much more limited by the factors Peter identifies. Finally, many of the intellectual “risks” one might take post-tenure (where “risk” is broadly defined as “trying new things”) don’t result in papers. Writing a book, for instance.
A final thought: the ecologists I can think of who did great, influential work late in their careers also did great, influential work early in their careers. Think David Tilman or Jim Brown, for instance. I’m not thinking of any “late bloomers”, ecologists who only did great, influential work late in their careers. Can you think of any? In evolutionary biology, how about John Maynard Smith? His career change from engineering to biology only partly accounts for the lateness of his great work on game theory and the major transitions in evolution. As far as I know, that late work is far more important than his earlier work on Drosophila. There’s George Price too, though he’s an unusual case because he bounced between jobs and fields for many years before doing the great work for which he’s now remembered. In a funny way, he was both a late bloomer (as a scientist) and a prodigy (as an evolutionary biologist specifically). A quick search reveals various suggestions for late bloomers in other scientific fields–see here, here, here, and here. But many of them seem to have been “late bloomers” only in the sense of “not prodigies”, which barely counts. Yes, it is unusual for someone who struggled as an undergrad to go on to a great scientific career, like, say, Craig Venter. But Venter started making an impact as soon as he got his first faculty position, so he didn’t bloom that late. For purposes of this post, I’m more interested in really late bloomers–people who spent many years as scientists before doing really outstanding work for the first time late in their careers. Bonus points if the great work wasn’t in large part an accident, as with Alexander Fleming’s discovery of penicillin.**
p.s. On another note: the data from the linked economics paper are difficult to reconcile with the view that senior academics easily get papers accepted and highly cited just by virtue of being senior.
*Which I’ve only skimmed, and so can’t fully vouch for. For instance, another commentator notes that the paper may not adequately allow for “Sleeping Beauties“–papers that only become highly cited after a long lag.
**Darwin doesn’t count. Yes, he was 50 when he published the Origin. But that was because he put off publishing for many years. He’d developed most of the major ideas and lines of evidence in the Origin by 1842, when he was only 34 and was just starting to make a name for himself in science.