The rock-paper-scissors game and coexistence

In 1975, R.M. May and W.J. Leonard first used the rock-paper-scissors game to model ecological scenarios in which three species cyclically dominate each other: one species dominates a second species, the second species dominates a third species, and the third species dominates the first species. The game works well, for example, for modeling different strains of cyclically dominant E. coli bacteria.