It’s been nearly 4 weeks since the 200th anniversary of Darwin’s birthday (this year also marks the 150th anniversary of the publishing of the Origin) and I’ve had some time to reflect. In case you missed it, the bicenntential received quite a bit of popular press, and was accompanied by numerous special journal issues and symposia within the scientific community. Anyway, I’ll just add a couple personal notes here.
I.
I spent my Feb. 12, 2009 rather uneventfully working through a recently published mathematical model of adaptation. Models similar to this one more or less got their start from Ronald Fisher’s thinking about the organism’s optimal phenotype (morphology, physiology, etc.) as a single point in a high-dimensional landscape, since many traits simultaneously contribute to fitness. While there are other ways to model the relationship between genes, phenotypes, and fitness, the crux of Fisher’s model and many that have followed from it, is that beneficial mutations are exceedingly rare and small. This is because in a high-dimensional space with a single optimum, most changes, esecially large ones, will move an organism further from that optimum, while only a few, generally smaller, will move you closer. The situation is complicated by the fact that beneficial mutations of larger effect are less likely to be lost due to random processes. Newer models, like the one I was reading about on Feb. 12, and additional data have for some time been challenging the highly idealized Fisherian view. However, even the newer models make many assumptions, do not provide a clear predictions about some aspects of adaptive genetic changes, and invoke parameters that are phenomonlogical rather than derived from first principles. All this is to say that we have a lot of work left to do.
The oddity of the situation struck me some time during the day: 150 years after Darwin published a convicing account of adaptation via natural selection that has since been corroborated countless times by new data, we still only have a rudimentary mathematical framework for making general predictions about adaptation. This state of affairs is not a problem for the fact of evolution or the mechanism of adaptation (natural selection), but, in my opinion, does pose a problem for the scientist trying to design studies that deepen our understanding of adaptation. Without rigorous models to test, crucial experiments are either not performed or undertaken in a conceptual vacuum, making them difficult to interpret.
II.
I was also contemplating the latest in the line of Gallup polls on evolution and creationism:
The results are not surprising; the percentages have stayed nearly constant since Gallup began the poll in 1982. Further data collected in this poll implicates the usual culprits: lack of education and religious belief (the latter being a stronger predictor than the former). What I do find a bit odd in the reporting is that many see the results in a half-empty light (e.g. “less than 4 of 10 accept evolution”), failing to note the large fraction of people (36%) with no opinion. While I am personally incredulous that over a third of the adult population could not care about the fact of evolution, I suppose there is little harm. I’m sure that many musicians are equally dismayed that I have no opinion or knowledge of Opera, but I can’t bring myself to care. Anyway, the results are still disappointing since so many people deny the facts and even the agnostic can still be easily enough swayed to allow teaching of creationism under the pretense of “hearing both sides”.
III.
On a note of self-congratulation, my first peer-reveiwed paper appeared online the night of Feb. 12 (the print edition didn’t arrive until the next day). You can read the abstract here. I’m author 7 of 18 – very Borgish.