Friday, February 24, 2006
It's only a couple of months since I've been able to renew my interest in evolution but I remember during the first period (which began about 1998) how the phenomena of stationary-phase/adaptive mutations immediately caught my attention.
The extracts below are from two articles which were fairly typical of those I came across at that time while trying to find out more about John Cairns et al.'s 1988 paper, The Origin of Mutants:
Directed Mutation (Science Frontiers):
Dear reader, things have a way of working out serially. For several months, we have had in our possession a paper from Nature, by J. Cairns, of Harvard, plus some passionate correspondence stimulated by the paper. Now that the circle-forming sheep have provided a good introduction, we will jump into the fray, too.
Basically Cairns (in Nature) and B. H. Hall (in Genetics) say that organisms can respond to environmental stresses by reorganizing their genes in a purposeful way. Such "directed mutation" shifts the course of evolution in a nonrandom way.
Such a conclusion was like waving a red flag in front of the evolutionists. R. May, at the University of Oxford, complained, "The work is so flawed, I am reluctant to comment." On the other side, a University of Maryland geneticust, S. Benson, comments, "Many people have had such observations, but they have problems getting them published."
As sentences in scientific papers go, this was guaranteed to raise eyebrows: "We describe here experiments and some circumstantial evidence suggesting that bacteria can choose which mutations they should produce."
The sentence appeared in a 1988 Nature paper, "The Origin of Mutants," by John Cairns, Julie Overbaugh, and Stephan Miller of the Harvard School of Public Health. The paper inflamed passions in the genetics and evolutionary biology communities and reopened an issue that biologists had considered long settled. Must mutations arise spontaneously, independent of natural selection and without regard to their potential usefulness? the Harvard researchers asked. Or do mutations sometimes arise as a specific response to the current needs of an organism?
It was while reading items such as these that I began to wonder to what degree 'cultural conditioning' played a role in both the interpretation of, and reaction to, natural phenomena.
On the basis of "History doesn't repeat itself but psychology does" I eventually wrote a small piece for my website entitled An Error In Associating Lamarck With 'Adaptive Mutations'? which has now been posted to the Main Blog. I feel its contents are still relevant in a general sense and would welcome any comments!