 Each point in the simplex corresponds to a particular mix of types of agents in the population that can represented by an ordered triplet \((z_1,z_2,z_3),\) where \(z_1\) is the fraction of the population that follows D, \(z_2\) the fraction that follow M, and \(z_3\) the fraction that follow H. Points closer to a vertex of the simplex thus represent mixes where more agents follow the strategy associated with that vertex. The replicator dynamic then summarizes the evolution of population states where the fractions of represented strategies change over time in proportion to their average reproductive fitness. Here a strategy’s average reproductive fitness corresponds to its average payoff relative to the average payoff of other strategies represented in the population at a given  time.[15]  To illustrate, in  Figure 12,  the point \(z_0 = \left(\frac{1}{6}, \frac{1}{3}, \frac{1}{2}\right)\) represents an initial state where \(\frac{1}{6}\) of the population follow D, \(\frac{1}{3}\) follow M, and \(\frac{1}{2}\) follow H. Given this starting point, the replicator dynamic then traces an orbit starting at \(z_0\) that converges to \(\be_2 = (0,1,0),\) the vertex point where the entire population follows the pure strategy M.