Ants are the most important insects in tropical rainforest. Deep into the Peruvian Amazon, in the biodiversity hot-spot of Madre de Dios area, two species dominate rainforest floor: the immense army ants colony of Eciton burchelli and the big and dangerous bullet ants Paraponera clavata. Two fascinating social insects and two very different lifestyles.
Army ants rely on huge number and aggressive cooperation. But given the size of their colonies, with tens of thousand of individuals, they must migrate in order to find food. They have no fixed nest and build a new bivouac, a huge aggregation of ants, each day during their nomadic phase. Eciton burchelli are in fact swarm raiders, foraging in a dense fan shaped swarms that can span ten meters across the forest floor and can be very intimidating. They seize everything, from other ants to beetles, scorpions and even small vertebrates not fast enough to move away. Army ants have a painful stings and their warriors show huge jaws that can even pierce the human skin. When the queen is laying eggs, once each two weeks, the colony stops in the same position for days. But will be ready to move again almost immediately, to collect more food for newly hatched larvae.
Bullet ants, Paraponera clavata, are exactly the opposite. Their colonies are far smaller, usually not much that one hundred individuals, and usually built at the base of a tree in permanent position. They have a unique working caste, the 2,5 cm long worker, armed with a deadly sting. They are said to be among the most poisonous insect in the world but luckily they are far less aggressive than army ants. The sting on human being is said to be extremely painful. Hence their American common name: “bullet ants”, big and deadly like rifle projectiles. These ants hunt alone on rainforest floor and trees and, given their weapons, can easily subdue most preys. But when a big insect is found close to the nest they can call reinforcements, like any other ant.
The two species do not seek open conflict at any cost but almost always meet each other. Deadly battles are the obvious consequence: bullet ants have strength and size, army ants aggressiveness and number. So the results of these skirmishes are often unpredictable and the fight keeps on. Ants do not know peace and diplomacy. As Edward O. Wilson, the most famous myrmecologist in the world said “If ants were given nuclear weapons the world would be destroyed within a week”.

On Ants see also The battle against Red Fire Ant