Ants can find their way home even when forced to walk backwards while carrying food, showing that they are capable of complex navigational behaviour.

Ants of many species walk forwards when carrying small items of food, but move backwards to drag larger items behind them. Antoine Wystrach at the University of Paul Sabatier in Toulouse, France, and his colleagues studied this behaviour in the desert ant Cataglyphis velox. During field experiments, forward-walking ants adjusted their course as they moved by recognizing the view of the surrounding scenery, but backward-walking ants did not. Instead, about one-third of these ants made occasional stops to peek forward, then corrected their direction on the basis of visual information. The ants were able to translate their forward view into an internal compass bearing, and maintain this direction in any body orientation.

This complex and flexible behaviour may require communication between at least two regions of the ant brain, the authors suggest.

Curr. Biol. http://doi.org/bxj6 (2017)