I enjoyed an essay by David Dobbs in Aeon Magazine about genes. Key to the argument is a call for more complex understanding of the relationship between genes and evolutionary change.
The gene-centric view is thus ‘an artefact of history’, says Michael Eisen, an evolutionary biologist who researches fruit flies at the University of California, Berkeley. ‘It rose simply because it was easier to identify individual genes as something that shaped evolution. But that’s about opportunity and convenience rather than accuracy. People confuse the fact that we can more easily study it with the idea that it’s more important.’
The gene’s power to create traits, says Eisen, is just one of many evolutionary mechanisms. ‘Evolution is not even that simple. Anyone who’s worked on systems sees that natural selection takes advantage of the most bizarre aspects of biology. When something has so many parts, evolution will act on all of them.
‘It’s not that genes don’t sometimes drive evolutionary change. It’s that this mutational model — a gene changes, therefore the organism changes — is just one way to get the job done. Other ways may actually do more.’
It seems to me that the arguments that the genetic code are read in different ways most challenges the notions about predictable genetic modification.
Describing Mary Jane West-Eberhard’s arguments about genes, Dobbs notes:
She does have her pithy moments. ‘The gene does not lead,’ she says. ‘It follows.’
There lies the quick beating heart of her argument: the gene follows. And one of the ways the gene follows is through this process called genetic accommodation.
I appreciate that it comes down to a battle of articulation — simple vs. complex. Communication, it always comes back to communication. Some ideas corrode against others and in this case the gene-centric model pushes out the ability to explain that ideas like the selfish gene . . . might be a little more complex than we think.
Yet West-Eberhard understands why many biologists stick to the gene-centric model. ‘It makes it easier to explain evolution,’ she says. ‘I’ve seen people who work in gene expression who understand all of this. But when they get asked about evolution, they go straight to Mendel. Because people understand it more easily.’ It’s easy to see why: even though life is a zillion bits of biology repeatedly rearranging themselves in a webwork of constantly modulated feedback loops, the selfish-gene model offers a step-by-step account as neat as a three-step flow chart. Gene, trait, phenotype, done.