Many replicators, genes, come together in one organism, or vehicle, but the unit of evolution is the gene. For those with some knowledge of evolution, they will debate the importance of the individual organism and the gene, but as Dawkins says, these are two separate entitites, not competitors. To view evolution in terms of genes, rather than individuals, may be a better working paradigm. The first ten chapters of this book, are as in the original, presenting many examples to support this paradigm shift, and make good reading in themselves. Dawkins original eleventh chapter was on memes.
Memes are ideas that can be replicated, such as the transmission of culture.
He thinks that human beings are unique in that they may consider memes as more important replicators than genes. This is an advance from evolutionary thought which tries to think of every behaviour in terms of a genetic advantage, but rather human beings may regard ideas as being more important. Some of his extrapolations to claim that faith is a selfish meme may be partially true, but it is a shame that he does not look beyond biological advantages into the spiritual world. This is an extrapolation Christians can make for themselves. The bibliography has been updated, which provides the general reader with useful original sources.