Leaf-cutter ants are known for their impressive carrying abilities, but what else do you know about them? Here are five quick facts to broaden your understanding of these impressive creatures.
1. Leaf-cutter ants don't eat the leaves they cut and carry to their nests. While it might seem like they're vegetarians creating a massive salad bar inside their nests, they're actually collecting those leaves to feed to their fungus gardens. It's the fungus they grow from the decomposing leaves that's their food. Yes, they need the leaves, but only in the way that we need fertilizer to grow our crops.
The fungus piles also release nitrous oxide, a greenhouse gas, into the atmosphere. "Leafcutter ant colonies are very organized, putting all their waste into colony dumps, much like our landfills or compost piles," researcher Fiona Soper explained in a study conducted by the University of Montana. "These landfills create ideal conditions for the bacteria that make nitrous oxide, creating point emissions that can rival human-engineered systems such as wastewater treatment plants."
The researchers also noted that the amount of nitrous oxide created by these fungus piles is comparable to the amount of gas released by anaerobic dairy manure lagoons.
2. A leaf-cutter ant colony is made of ants that fill different roles, such as workers and soldiers. But a surprising role is that of a tiny protector. There are ants whose job it is to protect leaves from parasitic flies and wasps. These ants, called minim ants, ride on the leaves and pluck off any parasites that could cause disease or destruction if the parasite made its way into the ant colony.
3. Leaf-cutter ant colonies can be up to 10 million ants strong, and they need space for all those ants plus their fungus gardens, nurseries, trash chambers and other chambers within their nest. So just how big can a leaf-cutter ant nest get? According to Marietta College:
"A large nest can have thousands of chambers, some of these may be a foot or so in diameter. Some chambers are used for brood, others for the fungal gardens and, in some species, there are chambers used for trash... Scientists studying the nests have used bulldozers to uncover them."
4. Starting a new colony isn't an easy job. And it's up to a young queen to give it her all if she wants to start a new colony. Winged ants, both females and males, leave their nests in large numbers to take part in what's known as a "nuptial flight" or "revoada."
A female and potential queen needs to mate with several males then return to the ground to find a place to start her fungus garden and begin a future colony. Only about 2.5 percent of queens will succeed in establishing a colony.
5. Leaf-cutter ants are incredible workers, and it's no wonder they're considered a major crop pest. They are able to strip a tree of its foliage in less than 24 hours. And studies show that more than 17 percent of leaf production by plants surrounding a leaf-cutter ant colony goes straight into that big, fungus-growing nest.
Editor's note: This article has been updated since it was originally published in January 2017.