Leafcutter ant carrying

Learn how leafcutter ants carry leaves to cultivate fungi, essential for ecosystems and agriculture.

About this subject

Leafcutter ants, belonging to the genera Atta and Acromyrmex, are known for carrying green leaf fragments into their underground nests. This behavior is not for direct feeding but to cultivate a symbiotic fungus that serves as their primary nutrition source. The relationship between ants and fungus is a classic example of mutualism: ants provide fresh plant material and protection from pests, while the fungus breaks down cellulose and produces enzymes that ants cannot digest on their own.

These ants are predominantly found in Central and South America, especially in Brazil, where they are common in tropical forests, savannas, and even urban areas. A mature Atta colony can house millions of individuals and excavate tunnels stretching dozens of meters. Leaf transport is performed by medium-sized workers, which cut pieces with sharp mandibles and balance them over their heads while following chemical trails marked by pheromones.

The activity of leafcutters has significant environmental impacts. By pruning trees and shrubs, they contribute to nutrient cycling and the opening of gaps that allow sunlight to reach the ground. However, in agricultural areas, they may be considered pests due to defoliation of crops such as eucalyptus, citrus, and sugarcane. It is estimated that Atta colonies consume about 10% of the plant production in their region.

Interestingly, leafcutter ants have a complex caste system with workers specialized in different tasks: the smallest tend the fungus and larvae, medium-sized cut and transport leaves, and the largest (soldiers) protect the colony. Leaf cutting is so efficient that a single colony can remove up to 500 kg of plant material per year.

Frequently Asked Questions

Why do leafcutter ants carry leaves?

They carry leaves to cultivate a symbiotic fungus that serves as food for the entire colony. The leaves are not eaten directly but serve as a substrate for fungus growth.

Where do leafcutter ants live?

They are found mainly in Central and South America, especially Brazil, in tropical forests, savannas, and agricultural areas. They build underground nests called anthills.

Are leafcutter ants harmful?

It depends on the context. In nature, they are important for nutrient cycling. In agriculture, they can cause significant damage by defoliating crops such as eucalyptus and citrus, and are considered pests.