Army ant colonies typically contain workers of many sizes, each specialized for a different task. Here a Nomamyrmex esenbeckii worker stands guard over a passing column. Gamboa, Panama

nomamyrmexantantsnatureinsectinsectspredatorsentomologyecitoninaeformicidaenomamyrmex esenbeckiibugspanamatropicalarmy antarmy antslegionary antsrainforestecologysocial insectspolymorphismworker caste