"The way I think about genes and genetic drift is as a clay sculpture of a beautiful woman's face. It's finely and delicately contoured. She has a pointed noise, raised cheek bones, large almond eyes, and a well defined chin that just sticks right out there. Then you get out a sandblaster and start blasting off the features around the main shape of the head. In the end, you've still got a head, but no ears, no nose, or mouth. Genetic drift is like the sandblaster that rips defined features off the organism. The resulting genetic variation can be thought of as the newly created real estate on the face. Now new things can be made!"