The idea that natural selection is the only mechanism that influences evolution has always troubled me: it seemed entirely too blunt an instrument to maximize fitness. An organism would inheret the genes of parents who survived long enough to reproduce, but what if radical changes in the environment took place faster than additional generations could adapt. Shouldn’t cues in the environment be used to alter the existing organism’s genes?
According to this article, they do.
The traditional idea that we are the passive carriers of our genes is being challenged by the notion that we are their custodians. Our lifestyles — what we eat, how much we exercise, whether we smoke — may play a role in a chemical switching system that activates or deactivates our genes. There are signs that our behaviour may program sections of our children’s DNA, and that how we live may even affect our grandchildren’s genes.
It seems the more we learn about DNA and genetics, the more we realize how little we do know.
[tags] DNA, genetics, pregnancy, epigenetics [/tags]