POST TIME: 24 January, 2019 12:42:22 AM
Construction without coordination
The way ants build megaprojects
AFP, Paris

Construction without coordination

Leaf-cutter ants build super highways to transfer food and building materials hundreds of metres without communicating with each other, scientists claimed yesterday, in findings that could prompt a rethink about how some insect communities organise themselves.

Each leaf-cutter colony can carve out nearly three kilometres of trails from the forest floor every year, investing an average of 11,000 hours into constructing and maintaining them. It had long been thought that the ants, which are native to south and central America, organise megaprojects by communicating with one another, assigning specialists to remove debris and retrieve leaf matter.

But an international team of researchers made a startling discovery while investigating the behaviour of one of nature's most impressive engineers. Far from communicating individual tasks as part of an overall plan, the ants appear to manage large-scale infrastructure projects with no coordination at all.

In other words: each ant seems to act alone, solving environmental problems such as removing obstructions as they are encountered. "Although many thousand individuals contribute to the construction of infrastructure, there is no communication or organisation between them -- the massive foraging trails are a byproduct of the foraging behaviour," said Thomas Bochynek, from Northwestern University's department of electrical engineering and computer science.

"This is surprising, because many collective behaviours are organised by communication," he told AFP.

The behaviour of social insects  such as ants, bees and termites is usually considered to be governed by stigmergy -- self-organisation through direct or indirect communication among individuals.