Altruism is a very heavily loaded word  in evolutionary psychology/ biology and I would not add to the confusion by defining the term myself. Suffice it to say , that I will use it in all of its various intuitive and theoretical usages. The evolution of

http://feedproxy.google.com/~r/TheMouseTrap/~3/OpyEo87DPz8/varieties-of-...

Generalized Reciprocity in Rats. Rutte C (2007) PLoS Biol.
January 13, 2009