Researchers at the Georgia Institute of Technology have done perhaps the only serious engineering study that involves dumping a bunch of fire ants in water and watching what happens. Engineering professor David Hu and grad student Nathan J. Mlot were interested in reports they had heard of South American fire ants forming massive rafts out of themselves and clumping together during flooding, and after gathering up fire ants by the roadside in Georgia, they put the anecdotes to the test.
“They’ll gather up all the eggs in the colony and will make their way up through the underground network of tunnels, and when the flood waters rise above the ground, they’ll link up together in these massive rafts,” Mlot said.
But in addition to making for some neat time-lapse videos, one of which is above, the researchers were doing science here: Among their findings were that ant groups of any size could fulls assemble a totally watertight raft in under two minutes, that “when the researchers removed ants one by one from the top of the raft, ants on the bottom moved up, to preserve the raft’s average thickness,” and that ants could live on the air bubbles trapped in the raft and food gathered from the nest before the voyage. And there may be practical applications as well:
[The researchers] said: “Overlooking its diminutive size and shortcomings in soapy solutions, the ant raft has attractive traits with respect to man-made flotation devices. It simultaneously provides cohesion, buoyancy and water repellency to its passengers. It can be constructed quickly, in approximately 100 seconds, without any additional equipment. It can accommodate thousands to millions of passengers with zero casualties. But, perhaps most strikingly, the ant raft is self-assembling.
Another video: (wait for the pushdown attempt)
(via National Geographic, Daily Mail)
Published: Apr 26, 2011 10:30 am