"When ant densities are high, each ant thoroughly searches one small area in a circular, 'random' walk," said Stefanie Countryman, the programme director.
"When ant densities are low, each ant searches by walking in a relatively straight line, allowing it to cover more ground."
It's hoped the data can be used to build robots that can 'forage' for themselves - perhaps by searching for people in a building too dangerous for people to enter.
Professor Deborah M. Gordon, of Standford University, an expert on animal collective behavior who helped devise the experiment, told Space.com that some really interesting biological changes occur in microgravity, for example, the way that nutrients circulate around cells or the way genes are expressed
"We have a lot to learn about how collective behavior changes in space," said Prof Gordon.
The behavior of the ants is being beamed back to earth, allowing school children to take part in the experiment. The ants arrived on the ISS aboard an Orbital Sciences Cygnus spacecraft on 12 January.
In 2012 a Johnson Jumper (Phidippus johnsoni) spider was sent to the ISS; scientists found that it adapted to microgravity well after a short time but that when it returned to earth it kept falling on its back after jumping, but then readapted to earth's gravity again after a short while.
- UK Independent