[jballanc]

That cooperation is eventually selected for has been known for decades, but we didn't know how. Yes, there have been many speculative models describing how cooperation might arise, kin selection being among the earliest of these. Each of these mechanisms has some applicability and some predictive power (for example, kin selection is pretty good at describing cooperation in everything up to and including eusocial insects), but we've been missing the general mechanism that has predictive power across all domains.

In other words, the field of evolutionary biology today has its Newton's laws and Maxwell equations, but we're missing anything like the Standard Model. The authors of this work have been at this for a number of years. A sophisticated analysis of the dynamics is a key and very important step in beginning to develop a "grand unified theory" of evolution.