Washington (Agencies): Ants, the social insects, are smarter than one can imagine—they can connect multiple sites in the shortest possible way, and in doing so, create very efficient transport networks, a new study has revealed.

"The findings highlight on how other 'simple' natural systems without leaders or even brains are able to form efficient networks, and can help humans design artificial networks in situations lacking central control,” Journal of the Royal Society Interface quoted Dr Tanya Latty of Sydney University, the study's lead author.

"Engineers face challenge to design transportation networks that cut resource use while still maintaining connectivity between sites such as cities.

"Argentine ants face the same dilemma as transport engineers. This species can form super colonies that consist of thousands of nests connected by a network of pheromone trails. Because longer trails need more pheromone to build and maintain, the ants would benefit greatly from building efficient networks with the shortest possible trail length."

To see whether Argentine ants could create inter-nest networks that cut trail length, the researchers gave ants the task of connecting three or four nests together. The nests were placed in an empty arena and the ants were allowed to join them in any way possible.

After two hours, the resulting ant networks were compared to networks that used the shortest trail length.

For each treatment, there were only two "efficient" keys that resulted in the shortest networks—the Minimal Spanning Tree, which joined the nests in the shortest way without adding an extra hub; and the Steiner Network, which used added hubs to connect the nests in shortest trail length.

The Minimal Spanning tree is the simplest way, but the Steiner network, with its added hubs, represents the most difficult but ultimately the most efficient route.

After two hours, the ants created networks that resembled both efficient solutions. They often created difficult Steiner Networks, adding a central hub in the three- nest treatment and two central hubs in four-nest treatment.

Dr Latty said: "It's interesting that the ants were able to create, on a blank slate, the mathematically shortest network between multiple points. This network design allows Argentine ants to distribute brood, workers and food between nests with extreme efficiency, and might help describe why they viciously out-compete other ant species outside their native home of South America.

"But just because the ants are as good as computers at solving network design problems, doesn't mean that they use complex processes. We found that networks set up through trial and error."