Monday, June 05, 2017

Game Theory and Antibiotic Resistance

I found an interesting article in Quanta Magazing discussing a 2012 paper in PNAS discussing game theory in the context of evolutionary processes. The article in Quanta is very detailed and nicely written as well as accessible.

This was interesting because in graduate school and other work I am familiar with, the context of games is defined around human-environment interactions leading to a Nash Equilibrium/prisoner's dilemma situation where the dominating strategies involve overuse of a given technology (antibiotics, herbicide resistant crops, insect resistant crops). In this context the equilibrium strategies create selection pressure which ultimately lead to insects, weeds, or bacteria that are resistant to the given technology. However, the Quanta article provides some examples where researchers are using game theory to describe actual behavior in nature (i.e. fish, monkeys, or the bacteria themselves). Here is a slice:

"For example, scientists studying antibiotic resistance are using a game theory scenario called the snowdrift game, in which a player always benefits from cooperating. (If you’re stuck in your apartment building after a blizzard, you benefit by shoveling the driveway, but so does everyone else who lives there and doesn’t shovel.) Some bacteria can produce and secrete an enzyme capable of deactivating antibiotic drugs. The enzyme is costly to produce, and lazy bacteria that don’t make it can benefit by using enzymes produced by their more industrious neighbors. In a strict prisoner’s dilemma scenario, the slackers would eventually kill off the producers, harming the entire population. But in the snowdrift game, the producers have greater access to the enzyme, thus improving their fitness, and the two types of bacteria can coexist."

Below is the citation related to the Dyson and Press paper discussed in the Quanta article:

Press, W. H., & Dyson, F. J. (2012). Iterated Prisoner’s Dilemma contains strategies that dominate any evolutionary opponent. Proceedings of the National Academy of Sciences of the United States of America, 109(26), 10409–10413.

No comments: