Genes are amazing things. They are storehouses of information. They are also able to copy themselves (with some help), and they are the reason I am here typing. In the 1970s, evolutionary biologist Richard Dawkins had an insight that propelled him to write a book called The Selfish Gene. It was a brilliant, carefully thought-out theoretical and philosophical breakthrough in biology. It was also badly misunderstood. In the years and decades that followed publication, people who had not actually read the whole book complained that genes are not really selfish, since they have no minds to entertain such notions, and anyway, the term selfish is a negative one, and it makes evolution seem like an evil doctrine (which creationists already agreed it was).
The book makes it quite clear that our concept of selfishness has nothing to do with the point. What Dawkins is saying is that genes are the key components of the evolutionary process that involves selection of the most fit varieties of life. And since genes are the ultimate controllers and determinants of all the characteristics of all living organisms, what we end up with are genes that create the best possible cellular structures and features to allow those genes to keep on existing.
In other words, the selfish gene concept was actually a distilled and targeted demonstration of the root mechanism of evolution – natural selection. This is possible because genes do two things extremely well, and these happen to be the two most important things in biology: they replicate themselves with a very high degree of accuracy, and they code for all of the phenotypic characteristics of the cell that are the target of natural selection.
Think of a school board that is trying to decide between two textbooks. They do an experiment in which one class of students uses one text, and another class uses the other text. The students who used the first book do better on an exam than did those who used the second. So the School Board decides to order more of book 1. The books are the genes, the students’ knowledge are the phenotypes, the exam is the environment, and the school board is natural selection. Textbook 1 (which the school board didn’t even read) survives and becomes the only book in use. Nothing selects the genes themselves, but when the information in the genes is translated into the phenotype of the cell, the selection of the better phenotype leads to the selection of the better gene.
Dawkins’ view is that while the bird with the better eyesight might be better adapted and outcompete its rivals, what is successful is really the gene in that bird that coded for the better protein that produced the better eyesight. The phenotype (including later, the extended phenotype) is only a means to the gene’s ability to survive and continue to prosper.
It really is a very nice, consistent, logical and convincing idea. It’s also probably wrong.
At least that is the conclusion I have recently come to. I have always been pretty much a gene-centric kind of guy. As I said in my last post, I took the side of the replicator-first faction in origin-of-life discussions. I worked with genes and DNA, and I loved the way all of biology seemed to make good scientific sense if one simply ignored all the rest of life and just focused on genes. But alas, I can no longer support that view.
Part of the reason I am undergoing a conversion to a non-gene-centric view is the kind of new data and concepts about the extended evolutionary synthesis that I have discussed here before. Another part is that the idea of the gene as the absolute master of all of biology is just too simple, and biology is never, ever simple. The resurgence of the Lamarckian heresy; the importance of epigenetic effects, which can even be inherited (more heresy); and all of the results on niche construction, genomic engineering, and, of course, gene expression, have exerted their influence on my thinking.
I am not comfortable with all of this non-genic stuff. It makes everything more complicated and a lot harder. But if it is actually true that there is more to life than genes, I suppose there is no avoiding this. I have more to say about the whole subject, and I will in a later post. Meanwhile, it might be time to retire that well-known phrase “He has to do it that way. It’s in his DNA”. The big question now is, what do we replace it with?