Sydney, Nov 25 (IANS): Army ants can build living bridges by linking themselves to span gaps and create shortcuts across rain forests, new research has found.

The team of researchers found that the bridges can assemble and disassemble in seconds.

"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 one of the researchers Christopher Reid from University of Sydney.

The bridges facilitate travel by the colony at maximum speed, across unknown and potentially dangerous terrains, the researchers said.

The bridges stop moving when they become so long that the increasing costs incurred by locking workers into the structure outweigh the benefit that the colony gains from further shortening their trail.

Bridges dismantle when the ants in the structure sense the traffic walking over them slows down below a critical threshold.

The findings could be applied to develop swarm robotics for exploration and rescue operations. By analysing how ants optimise utility, to allow swarms of robots to behave in similar ways to an ant colony, Reid noted.

"These systems could also enable robots to operate in complex unpredictable settings, such as in natural disaster areas, where human presence is dangerous or problematic," Reid concluded.

The findings were detailed in the journal Proceedings of the National Academy of Sciences (PNAS).