Ants Use the Sun for Guidance When Walking Backwards

Posted on January 19, 2017

Myrmecia piliventris

Ants often walk backwards when they are dragging large pieces of food and other items back to the nest. The photograph above shows an a backwards walking ant (Myrmecia piliventris) dragging an earwig back to its nest in Canberra, Australia. Scientists have discovered that ants rely on both the sun and their memories to help them find their way home while walking backwards.

An international team of scientists, including researchers at the University of Edinburgh, studied a colony of desert ants to see how they navigated while walking backwards. The researchers sunk barriers into the ground to create a one-way route to the nest. They then gave the ants a small or large piece of cookie, and observed how they made their way home.

The researchers found that ants traveling backwards with the large piece of cookie used the sun's position in the sky to guide them. They scientists used a mirror to alter the ants' perception of the sun's location. The mirror caused the ants to walk the wrong way. The ants set off in the wrong direction when the mirror was used.

Professor Barbara Webb, of the University of Edinburgh's School of Informatics, says in a statement, "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. Understanding their behaviour gives us new insights into brain function, and has inspired us to build robot systems that mimic their functions."

A research paper on the study was published here in the journal, Current Biology.

Photo: Ajay Narendra