The link is to an absolutely fascinating discussion of market economics in plants and animals. The low down is that the fewer neurons the organism has, the more rational it tends to behave. The guests observed and experimented with everything from capuchin monkeys to fish to fungi with regard to market exchanges of food, sex and services.
http://freakonomics.com/podcast/animal-economics/
http://freakonomics.com/podcast/animal-economics/
