Seed predation can actually weaken the coexistence of competing annual plants by reducing competition intensity. This happens because predation lowers population densities, weakening competition and replacing it with "apparent competition" that doesn't vary with the environment. As a result, the advantage of a species at low density is reduced, making it harder for different species to coexist. This study shows that in some cases, predation can hinder the ability of plants to live together peacefully in a variable environment.