Ever wondered how ants find their way straight to the uncovered food in your kitchen? Now scientists have discovered how the humble wood ant navigates over proportionally huge distances, using just very poor eyesight and confusing and changing natural landmarks. The research could have significant benefits in the development of autonomous robots and in furthering our understanding of basic animal learning processes.
Scientists at the University of Sussex, funded by the Biotechnology and Biological Sciences Research Council (BBSRC), have shown precisely how the ant's visual navigation strategy works. On a wood ant's first trip to a food site it follows a chemical trail left by earlier ants. This is a slow way of travelling as the ant needs to walk with its antennae to the ground. However, this initial route forms the basis of an efficient learning strategy. On the first trip ants store images of the route as they travel and on later trips to the food site will navigate using a combination of landmarks and memories of the whole landscape. The scientists found the ants even used different sets of landmark memories depending on whether they were on their way to food, or whether they were full and heading back to the nest. Ants store many memories and have mechanisms to activate the right ones.
The researchers refined their research on ant visual memory selection in lab experiments. Research leader, Professor Tom Collett from the University of Sussex's Centre for Neuroscience, explained: "To show that ants use visual memory to navigate we trained ants to find food 10cm from a cylinder. We then doubled the size of the cylinder and the ants searched for the food at 20cm away where the retinal size of the landmark was the same."
To analyse the ants' powers of recall an ambiguous situation was set up. Ants were trained to search for food between two cylinders of different sizes and then tested with the training cylinders replaced by two cylinde
Contact: Matt Goode
Biotechnology and Biological Sciences Research Council