Teamwork is not just a human trait: colonial weather ants will form living ‘scaffolding’ to protect members from falling.
The insects are blind and have no designated leader, but according to new research, they can use simple rules of conduct to develop these safety structures without the need for direct communication.
After a scaffolding was built, the working ants were almost 100 percent protected from falling on steep slopes.
The researchers say understanding how they design such complex structures can help engineers develop self-healing materials and swarm robots.
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Weather ants in Central American rainforests will build scaffolding out of their bodies to help them traverse steep terrain. The ‘safety net’ retains its structure even over virtually vertical slopes
There are more than 200 different species of weather ants (Eciton burchellii), which are mostly found in the rainforests of Central and South America.
To pierce the treacherous forest floor, working ants form ‘highways’ and ‘bridges’ with their bodies.
Researchers have discovered a new kind of architecture of the army ants, a living scaffolding that prevents ants carrying prey for the colony from slipping and falling if the trail becomes too steep.
An international team of entomologists studied the structures created by colonial weather ants in Panama.
The scientists diverted the food path of the colony to a platform that could tilt them up to 90 degrees horizontally
The scientists redirected the colonies’ hiking trails to a platform that could tilt them up to 90 degrees horizontally, and observed the creation of this scaffold.
There seems to be a nice place: according to their report this week in Proceedings of the National Academy of Sciences in the US, it probably wouldn’t cause anything below 40 degrees.
According to a release, much steeper slopes ‘led to larger and faster growing structures’.
“Scaffolding will also be more shaped when many workers are transporting heavy prey items,” said biologist Matthew Lutz, co-lead author of the study.
Virtually no ants fell once a scaffold was in place, even over vertical surfaces.
Anything below a 40 degree incline is unlikely to cause a scaffold to form. The steeper the slope, the faster and larger the structure
“It is remarkable how quickly these structures form due to disruption during the intersection of slopes,” Lutzsaid said.
“It really is a form of self-healing, responsive infrastructure.”
Army ants are the largest on earth, and each queen has the ability to lay several million eggs each month.
Millions of workers are constantly looking for food and consuming up to 500,000 larvae, eggs and other tasty pieces every day.
Each ant is only a quarter to a half centimeter in size, but the food trail of a colony can be more than 325 feet long and 60 feet wide.
Scientists do not yet fully understand how the ants form these superstars: they are virtually blind and although they have a queen, there is no central authority when it comes to moving as a unit.
Scientists do not yet fully understand how they form these superstructures: although they have a queen, there is no central authority when it comes to moving as a unit.
In addition, army ants are virtually blind and rely on pheromones to communicate.
The researchers – which included experts from the Max Planck Institute for Animal Behavior in Konstanz, Germany; Macquarie University in Sydney, Australia; the New Jersey Institute of Technology; and the Santa Fe Institute in New Mexico – theories that ants can sense how much they slip and spontaneously form these scaffolds when they lose their grip.
Weather ants are the largest species of ants on earth and each queen has the ability to lay several million eggs each month.
“Our model closely matches the experimental results, without the ants having to communicate with each other or assessing the size of the structure,” says co-lead author Chris Reid, a researcher at Macquarie University.
‘Army ants are small, blind and have no leaders or blueprints to target, but their ability to generate sophisticated group-level behavior from simple rules at the local level is very valuable to many engineering fields, including swarm robotics.
If the code is cracked on how they generate these structures with little input or information, it can bless robotics, architecture and engineering.
A swarm of miniature robots could possibly be sent to a disaster site and form a necessary structure to help with recovery, regardless of whether it was ‘programmed’ in advance in their network, the authors write in The Conversation.
Other ants also create structures: colonies of fire ants will form ‘floats’ to drive out a flood to safety.