http://www.newsweek.com/nasa-space-mice-race-tracking-behavior-1393156

Scientists have discovered that when sent to space, mice engage in an unusual behavior where they started doing laps of their cage in a “coordinated group activity.”

The mice were sent to the International Space Station in the NASA Rodent Habitat. This experiment, led by April Ronca, of the NASA Ames Research Center, was to study how their behavior might change during a long duration spaceflight.