Memeplex

Much of the study of memes focuses on groups of memes called "memeplexes", "meme complexes" or "memecomplexes" — such as religious, biological organisms, cultural, or political doctrines and systems. Some selfish genes propagate more effectively together. Similarly some memes propagate more effectively together; they are called memeplexes. Examples are sets of beliefs like acupuncture and astrology, sets of traditions like Christmas celebrations, circumcision, languages, political ideologies, religions and scientific theories.

These conceptual Memeplexes can be true and useful or false and harmful to the mind carrying them, yet are able to self-propagate. 

Religion
Memeplexes of religion provide a common example. In the case of Christianity, the theory suggests, the Christian memeplex evolved the Jewish religious teachings to form, among others, the Catholic church. Following the schism between the Catholic and the Eastern Orthodox churches, and later splits giving rise to various Protestant churches. Various people have added and deleted individual memes, resulting in the formation of completely different memeplexes (religions/sects) within the basic umbrella of Christianity, as well as within, for example, the Catholic, Orthodox, and Protestant traditions.

Different memes in a memeplex can interact to reinforce each other. For example the Christian belief that non Christians go to Hell can make Christians reluctant to examine their doubts and see if their belief is rational or not. Hope of Salvation can encourage people to become Christians or remain Christians.

Biology
Dawkinsian evolution, unlike the classic Darwinian model sees the Gene itself as the basic unit upon which Natural selection occurs. Thus it is not only the organism that it being selected for better fitness, but the Genes themselves create a useful memeplex for self-propagation, that plex is the organism itself. A good example of this is the default status for mitosis in animal cells, that without proper signaling from the body will commit suicide. This self-inflicted death occurs in order to support other copies of themselves that facilitate the rest of the propagation machine, thus creating the pre-cancer apoptosis mechanism. This balances the selfish will of the cell for self replication with the cells-memeplex will to further propagate specialized complex-cells in order to actuate the existence of the cells individually as a whole. This can be seen as co-evolution of the cells, to sacrifice themselves, much like ants do, for the good of the genetically similar colony.