Source: http://www.vox.com/2015/4/1/8325391/ants...

The formal experiment was a test of whether the ants could coordinate to search their environment, as they do on Earth. At the start, they were housed in a small corner of their plastic box, but over the course of a few minutes, astronauts removed barriers from it, allowing them to access new territory.

A comparison group of ant colonies on Earth were able to spread out and survey the entire environment within five minutes. Because of the difficulties of microgravity, the space ants weren't able to cover all the territory within the same time period, but they still managed to spread out and see most of it.