It's up behind a paywall (probably... with my university connection I'm never sure what has it and what doesn't) here: http://www.nature.com/nature/journal/v466/n7310/full/nature0... . If anybody is more mathematically sophisticated than I, wants to tackle it, but can't get through the paywall, send me an email (in my profile).
Skimming through the supplemental information, it seems like they assume a Markov process where individuals adopt one of two strategies (with a preference towards adopting the strategy that their parent adopted), then look at which one is more likely to be dominant in the population.
Skimming through the supplemental information, it seems like they assume a Markov process where individuals adopt one of two strategies (with a preference towards adopting the strategy that their parent adopted), then look at which one is more likely to be dominant in the population.