Nepedia
Back to Discover
Advanced Reader
🧬

Weaver ant

life science Maturity 5-7 Next article →

Weaver ants, also known as green ants, are highly organized insects belonging to the tribe Oecophyllini.

Two weaver ants
Two weaver ants

These ants are obligately arboreal, which means they live their entire lives in trees. They are famous for their unique method of nest construction. Unlike many other insects that live in soil, weaver ants build complex structures by weaving living leaves together.

AntsStitchingLeave
AntsStitchingLeave

A single colony can be massive. These colonies may consist of more than half a million workers living in hundreds of separate nests. These nests can spread across many different trees to form a large, interconnected community.

The process of building a nest is a remarkable display of coordinated labor.

AntsStitchingLeave
AntsStitchingLeave

First, worker ants survey potential leaves by pulling on their edges with their mandibles. If two leaves are too far apart for one ant to reach, the workers form long chains. They do this by grasping each other's petiole, which is the narrow waist of the ant. These living chains act like a "force ratchet" to pull the leaves together. Once the leaf edges meet, workers retrieve larvae from existing nests. They carry these larvae to the seam and tap them on the head. This action causes the larvae to excrete silk, which the ants use to bind the leaves together.

AntsStitchingLeave
AntsStitchingLeave

A large nest can be completed in less than 24 hours.

Weaver ant colonies show a clear bimodal size distribution among their workers. This means there are two distinct sizes with almost no overlap. Major workers are significantly larger, while minor workers are approximately half that length.

Weaver ant queen 4
Weaver ant queen 4

These sizes determine their specific roles within the colony. Major workers are responsible for foraging, defending the territory, and expanding the nests. Minor workers generally stay inside the nests. They focus on caring for the brood and "milking" scale insects for food. Scale insects, which are part of the Hemiptera group, excrete a carbohydrate-rich liquid called honeydew.

Oecophylla smaragdina tending
Oecophylla smaragdina tending

The ants consume this honeydew to supplement their diet of small insects.

There are two main extant species within the genus Oecophylla. One is Oecophylla longinoda, which is distributed throughout the Afrotropics. The other is Oecophylla smaragdina, which lives in India, Sri Lanka, Southeast Asia, and northern Australia.

Two weaver ants
Two weaver ants

In Australia, these ants can be found in tropical coastal areas from Western Australia to Queensland. The genus is quite old, with 15 fossil species described from the Eocene and Miocene periods. The oldest fossils of the Oecophyllini tribe were found in the mid-Ypresian Eocene of Northwestern North America. While other genera like Polyrhachis also use larval silk, the architecture of Oecophylla nests is much more complex.

Humans have interacted with weaver ants for many centuries. In Southeast Asia and China, farmers have used them as natural biocontrol agents since at least 400 AD.

Oecophylla smaragdina tending
Oecophylla smaragdina tending

Because weaver ants prey on insects that damage crops, they help protect fruit trees. This practice can lead to higher quality fruit and less leaf damage from herbivores. Using ants can be more efficient and cheaper than using synthetic chemical pesticides. Some farmers even practice husbandry by providing ropes between trees to help the ants move. However, the relationship is complex because the ants also protect sap-feeding insects like scale insects to collect their honeydew.

Weaver ants are also studied for their incredible teamwork. Researchers have noted that weaver ants increase their individual effort as the group size grows. This is different from how human teams often behave.

AntsStitchingLeave
AntsStitchingLeave

Their ability to coordinate many individuals to perform a single task is very efficient. This behavior provides valuable insights for the field of robotics. Scientists believe that mimicking these ant strategies could help improve autonomous systems. By studying how multiple agents cooperate, engineers may develop better multi-agent robotic systems.

Communication is the key to how these ants maintain such a large society. They use both chemical and tactile signals to share information.

SSL12022p
SSL12022p

For example, successful foragers lay down pheromone trails to lead other workers to food. They also use pheromones to recruit workers to defend against intruders. Tactile signals, such as body shaking or attenuation, help stimulate activity in other ants. They even use social carrying, where one worker carries another in its mandibles to a location that needs help. This combination of signals allows the colony to self-organize and respond to the environment effectively.

714 words

Where will your curiosity go next?

Keep exploring at your chosen reading level.

🖼️ Images & Media (7)
File:Weaver ant queen 4.jpg
Weaver ant queen 4.jpg
File:SSL12022p.jpg
SSL12022p.jpg
File:Two weaver ants.JPG
Two weaver ants.JPG
File:AntsStitchingLeave.jpg
AntsStitchingLeave.jpg
File:Weaverantnest05268.jpg
Weaverantnest05268.jpg
File:Oecophylla smaragdina tending.jpg
Oecophylla smaragdina tending.jpg
File:Ants Eggs Market Thailand.jpg
Ants Eggs Market Thailand.jpg
More to explore

🔬 Go deeper

More advanced topics to explore

🪜 Step back

Simpler topics to build understanding

What is Nepedia?

A free, ad-free encyclopedia for children. Every article is written at five reading levels, so the same page works for a five-year-old and a fifteen-year-old — use the level switcher above to see this one change. No account needed to read.