I'm currently reading Gary Marcus' The Birth of the Mind
The reason that animals can learn is that they can alter their nervous systems on the basis of external experience. And the reason that they can do that is that experience itself can modify the expression of genes.
The role of genes is not just to create the brain and body of a newborn, but to create an organism that is flexible enough to deal with an ever-changing world. Genes play an important role throughout life, not just until the moment of birth, and one of the most important ways in which they participate throughout life is by making learning possible.
I like how, in another section of the book, Marcus explains how genes are like functions. Immediately, in my mind flashes: f(x)=...
. Or maybe it's more like: geneX(experience, memory);