The basic economic model is often called “selfish”, but this is a misnomer. What separates economics from other cultural sciences is the assumption that humans are optimizers – that is, that they have an objective which they attempt to maximize. For this reason, economics has traditionally been wary of models, common in other social sciences, that apply genetic evolution theory to cultural objects. Traditionally, this has meant something along the lines of “if A interacts with B, A’s meme spreads to B with some probability” and then investigating the diffusion through society. With such a model, altruism could diffuse, for instance, if it helps the group as a whole survive. This is directly opposed to the idea that humans are maximizers, since regardless of group benefit, individuals may not wish to go along with “cooperate” just because they have heard the idea.
Nonetheless, this recent review by three Belgian social scientists argues that evolutionary biology has a lot to teach social science. In particular, they offer well-developed models of simulation. To the extent that economics, in the aggregate, *looks like* meme diffusion, then these models can still be useful. Therefore, I see proving equivalence between individual self-interested behavior and memetic spread as a useful direction for economists to investigate; for instance, is there a way to collapse, for some class of utility maximization, innovation choice such that at the population level innovation diffusion under utility maximization just looks like memetic diffusion?
http://bio.kuleuven.be/ento/pdfs/wenseleers_etal_tree_2009.pdf