Ants "can navigate successfully under many difficult conditions, including going backward".
Despite their tiny size, ants are sophisticated navigators that can find their way even while walking backwards, and these skills could help inspire better robots, scientists say.
The findings in this week's edition of the journal Current Biology are based on a colony of desert ants that were studied to see how they navigated home while carrying pieces of a cookie.
Carrying small bits, they walked forward. But with larger pieces, they dragged them backwards toward their nest, occasionally dropping the food to check the sun's position and reorient themselves.
Researchers said this practice of checking the environment and matching their progress against their memories of their surroundings shows the insects' mental capacity is more complex than previously thought.
"Ants have a relatively tiny brain, less than the size of a pinhead. Yet they can navigate successfully under many difficult conditions, including going backward," said co-author Barbara Webb, a professor at the University of Edinburgh's School of Informatics.
"Understanding their behavior gives us new insights into brain function, and has inspired us to build robot systems that mimic their functions."
Researchers say the ants' process could be useful to people, because it could help them develop new computer algorithms to guide robots.
The research team included scientists at the University of Lincoln, Australian National University, and the French National Center for Scientific Research (CNRS).