Game theory applies to all living organisms. I was recently saying this to a surprised undergraduate. Yet, it is true, as this blog post from Not Exactly Rocket Science illustrates: Cooperating bacteria are vulnerable to slackers : Not Exactly Rocket Science. It tells the story of a kind of bacterial colony in which some members freeload on the efforts of the others to make the environment more nourishing for all members of the colony. In a range of population sizes of the colony, the freeloading bacteria do so well that they multiply faster than the rest. This advantage dissipates, however, when they become so preponderant in the population of the colony that the whole colony is weakened. It seems like these bacteria have figured out how to deal with the “tragedy of the commons”, where people (or living creatures of any kind) overexploit a common resource because it is in the benefit of each individual to do so, even if it harms the group.