Evolutionary biologist Richard Dawkins is best known for his landmark book “The Selfish Gene,” in which he suggests that Darwinian selection happens not on the level of the individual but at the level of our DNA. Also introduced in that book is the concept of the “meme,” a self-replicating unit of culture — an idea, a melody, a rumor — which is passed along from one person to another, its longevity based on its ability to lodge in the brain and inspire transmission to others. Dawkins has recently been at the forefront of conversations about atheism. His 2006 book “The God Delusion” offered a critique of religion and promoted scientific principles over creationism and intelligent design. His most recent book, “An Appetite for Wonder” is a memoir covering his early life in colonial Kenya, his intellectual awakening at Oxford, and the creation of his books and philosophy.