Selfish Genes vs. Memes

1. The Selfish Gene theory: Basically, this says that evolution does not train organisms to survive and reproduce; it trains them to help their genes survive and reproduce. This means that a person or animal should sacrifice his/her/its life to save enough of its relatives. A simple example of this occurs in honeybees. The workers are willing to sting intruders (and thus die) in order to protect the queen because it is only through the queen that their genes can reproduce. According to the Selfish Gene theory, different behaviors in organisms (include social whatevers in humans) are the result f genes trying to ensure their own survival. To the best of my knowledge, this is the most influential new idea in biology in the last few decades. It also works just fine (with a few minor changes) in a Creationist worldview, so those people do not have to feel left out.
2. Memes: This is the weird but cleaver idea of treating ideas as quasi-living things (called memes) in a competition to survive and reproduce. For example, suppose I believe that the Martians have launched an invasion fleet that will reach Earth next Tuesday. If I then convince someone of this, the "Martian invasion" meme has reproduced, and now lives in two minds. If we convince a third person, the idea reproduces again. Eventually, Tuesday comes, the Martian fleet does not come, and we all stop believing in it. The Martian invasion meme has now died. Although this meme was pretty weak, some (e.g. democracy, the scientific method, Christianity, feminism) are powerful enough to change the world. The idea of memes is, in itself, meme, and I think deserves to reproduce more widely.