A meme is encoded in another host's brain through reconstruction using creativity by observing behavior of another host. The meme is not copied like in machines, but rather it is guessed and inferred from behavior. The meaning is being copied in humans, not necessarily through imitation. (David Deutsch, in The Beginning of Infinity, Chapters 15-16)
Animals (parrots, apes) usually have a lower form of encoding, that focuses on imitation instead of creative inference of the meaning.