Cooperating with your neighbours

Why do individuals cooperate? Let’s take a simple example where there are two kinds of individuals in a population: one cooperative (green) and one less cooperative (violet). Over time, the population will grow to colonise all of the available space. In order to claim a free spot on the grid, individuals require help. Of course, getting help from a cooperative (green) individual is much better than being helped by a less cooperative individual (violet). The non-cooperatives can get help from the cooperative individuals, and never waste valuable reproduction opportunities by replicating someone else. However, when left by their own devices, they are very bad at replicating. Who will win, and why? Let's find out!