Army ants build bridges with their own bodies to cross gaps in the rainforest floor, and scientists have caught the incredible feat on video.  

The findings demonstrate how these industrious ants move from their original building point to create a bridge, and change position as necessary, the University of Sydney reported. The researchers found the bridge stops moving when it become so long that the cost of locking new ants into the structure outweigh the benefits gained from taking the shortcut.

The bridges can be assembled or disassembled in a matter of seconds, and can move to fit changes in the environment. They facilitate maximum speed across the treacherous rainforest floors of Central and South America. In the past, scientists believed these structures remained relatively static once they were built.

"Indeed, after starting at intersections between twigs or lianas travelled by the ants, the bridges slowly move away from their starting point, creating shortcuts and progressively lengthening by addition of new workers, before stopping, suspended in mid-air," said co-lead author Christopher Reid, a postdoctoral researcher at the University of Sydney's Insect Behaviour and Ecology Lab and formerly with the New Jersey Institute of Technology.

The researchers believe their observations of this amazing natural phenomenon could be used to improve swarm robotics for exploration and rescue operations. Scientists could create simple algorithms inspired by army ants to direct robots to behave in a similar way.

"Artificial systems made of independent robots operating via the same principles as the army ants could build large-scale structures as needed," Reid said.

"Such swarms could accomplish remarkable tasks, such as creating bridges to navigate complex terrain, plugs to repair structural breaches, or supports to [stabilize[ a failing structure."

The findings were published in a recent edition of the journal Proceedings of the National Academy of Sciences.