JIJITANG2014-07-22 8:46 PM

ANTS CLUTCH EACH OTHER TO BUILD AN AMAZING LIFE RAFT

In a flood, fire ants grip each other with their mandibles and legs at a force of 400 times their body weight to build waterproof rafts to stay alive.

Now, using a miniature CT scan machine, researchers have frozen ant rafts and taken a closer look at the strongest part of the living structure—the inside—to discover how opaque ants connect, arrange, and orient themselves with each other.

“Now we can see how every brick is connected,” says David Hu, assistant professor of mechanical engineering at Georgia Institute of Technology. “It’s kind of like looking inside a warehouse and seeing the scaffolding and I-beams.”

He found a lot of beams.

On average, each ant in a raft connects to 4.8 neighbors. Ants have six legs, but using their claws, adhesive pads and mandibles, each critter averages nearly 14 connections. Large ants can have up to 21.

Out of the 440 ants scanned, 99 percent of them had all of their legs attached to their neighbors. The connectivity produces enough strength to keep rafts intact despite the pull of rough currents.

Hu and colleagues also noticed the insects use their legs to extend the distances between their neighbors.

SMALL ANTS FILL THE GAPS

“Increasing the distance keeps the raft porous and buoyant, allowing the structure to stay afloat and bounce back to the surface when strong river currents submerge it,” says Nathan Mlot, a graduate student who worked on both studies.

The researchers found that smaller ants tend to fill in the spaces around large ants. This keeps water from seeping in and prevents weak spots in the raft.

The insects, large and small, arrange perpendicularly rather than parallel. This adds to the adaptability of the raft, allowing it to expand and contract based on the conditions. The same is true when ants build towers and bridges for safety and survivability.

One thing the CT scan can’t solve, however: how the ants know where to go and what to do. Their cooperation is a mystery the research team hasn’t yet figured out.

“Fire ants are special engineers,” Hu says. “They are the bricklayers and the bricks. Somehow they build and repair their structures without a leader or knowing what is happening. They just react and interact.”

Better understanding of this phenomenon could lead to new applications for people and machines, Hu says. For instance, he envisions robots that can link together to build larger robots or bridges made of materials that can self-repair.

“If ants can do it, maybe humans can create things that can too.”

The National Science Foundation partially funded the research, which is published in the Journal of Experimental Biology.

Original Article:
Fire ants actively control spacing and orientation within self-assemblages
http://jijitang.com/note/5343

KEYWORDS

SHARE & LIKE

COMMENTS

ABOUT THE AUTHOR

JIJITANG

0 Following 3 Fans 0 Projects 310 Articles

SIMILAR ARTICLES

Changes to the Special Supplemental Nutrition Program for Women, Infants, and Children (WIC) have resulted in families eating more fruits and vegetable

Read More

In contests drawn from game theory, chimpanzee pairs consistently outperform humans in games that test memory and strategic thinking.A new study, condu

Read More

Publishing is one of the most ballyhooed metrics of scientific careers, and every researcher hates to have a gap in that part of his or her CV. Here’s

Read More

Pornography triggers brain activity in people with compulsive sexual behaviour -- known commonly as sex addiction -- similar to that triggered by drugs

Read More

In a recent survey, academic staff at the University identified the interrelated skills of writing and reasoning as the two most important skills for s

Read More

In a recent survey, academic staff at the University identified the interrelated skills of writing and reasoning as the two most important skills for s

Read More

Reading cautionary tales like The Boy Who Cried Wolf and Pinocchio to little kids might not be the best way to teach them to tell the truth.New researc

Read More

Those flat, glassy solar panels on your neighbor’s roof may be getting a more efficient makeover, thanks to a new class of solar-sensitive nanoparticle

Read More

Physicists have overcome a major challenge in the science of measurement using quantum mechanics. They’ve used multiple detectors to measure photons in

Read More

If you want to slow down long enough to smell the proverbial roses, you might want to move to a neighborhood with fewer drive-thru restaurants, researc

Read More