As Dawkins writes with such fluency and clarity, but his topic is scientific, critics have generally been concerned with his theories and content of the book rather than his style per se. The selfish gene theory has not been without its criticisms. Dawkins has been engaged for years in a running battle with the religious fraternity over the origins and development of life because his theories are so incompatible with religion.
More specifically, critics argue that it is not possible for a gene to be considered selfish or altruistic. They claim that to be selfish is to make a decision or perform an act which is to your benefit at the expense of others. They argue that genes do not make decisions or perform acts. Mary Midgley, in the journal "Philosophy" goes as far as to say: "Genes cannot be selfish or unselfish, any more than atoms can be jealous, elephants abstract or biscuits teleological".
Other criticisms are aimed at more specific ideas in the book rather than the book as a whole. For example, Dawkins describes the behaviour of baby cuckoos in respect to them ejecting the other species of bird eggs out of their own nest. This is simply explained in terms of the selfish gene. However, he goes on to report that the same behaviour has been observed in the Spanish baby swallow when one was placed into a magpie's nest, and suggests that this doesn't have anything to do with the fact that it's a different species, rather an attempt to lower the clutch size to increase the chances of it's genetic survival.
Dawkins writes; "He can acquire a ¼ share (of the food) simply by tipping out one egg; a 1/3 share by tipping out another. Translating into gene language, a gene for fratricide could conceivably spread through the gene pool…". However, this seems to oppose a lot of what The Selfish Gene says on genemanship. Baby swallows are not accustomed to finding themselves in magpie nests, they are never normally found in any nest except their own. Therefore, one must assume that the swallow thinks that it is in its own nest. Therefore, by tipping out one of the eggs, you are directly killing one of your siblings and consequently some of your genes. This is contrary to the Selfish Gene theory because any replicator coding its survival machine to kill their brothers and sisters would greatly reduce the chance of success of the genes.
Memes are also the focus of much criticism as nobody has succeeded in forging a scientific basis for the theory of meme transmission. This is mainly because they do not have a material existence like the genes, genomes and viruses and are therefore hard to pin down as notions of the soul or spirit. Whereby Darwin originally formulated his theory on evolution from studying the different characteristics of the finches beaks, memeticists has nothing physical like this to fall back on. Another problem that faces memetics is that the human brain is clearly not a passive vehicle for ideas. We don't simply soak up information and pass it on in a slightly mutated form, as our gonads might do with our genes - we process, criticise, edit and put our own spin on it. Therefore, simply trying to determine exactly what the meme replicator is proves to be difficult.
However, it seems that any criticisms that have been aimed at the Selfish Gene theory have only been attempted to shoot holes in it but as yet there has not been anything that has totally rocked the theory and disproved it.