The evolution of memes

"Since a person can enact and transmit a meme soon after receiving it, a meme generation can be much shorter than a human generation. And many cycles of variation and selection can take place inside the minds concerned even during one meme generation. Also, memes can be passed to people other than the holders’ biological descendants. Those factors make meme evolution enormously faster than gene evolution, which partly explains how memes can contain so much knowledge. Hence the frequently cited metaphor of the history of life on Earth, in which human civilization occupies only the final ‘second’ of the ‘day’ during which life has so far existed, is misleading. In reality, a substantial proportion of all evolution on our planet to date has occurred in human brains. And it has barely begun. The whole of biological evolution was but a preface to the main story of evolution, the evolution of memes."