Bees solve ‘Travelling Salesman Problem’

Researchers at Queen Mary and Royal Holloway, University of London have discovered that bees learn to fly the shortest possible route between flowers even if they discover the flowers in a different order.

Bees are effectively solving what is widely known as the ’Travelling Salesman Problem’, and are the first animals that have been found to do this.

The ’Travelling Salesman’ must find the shortest route that allows him to visit all locations on his route. Computer programs solve the problem by comparing the length of all possible routes and choosing the shortest.

Prof Lars Chittka from the Queen Mary School of Biological and Chemical Sciences said: ’In nature, bees have to link hundreds of flowers in a way that minimises travel distance, and then reliably find their way home – not a trivial feat. Studying how bee brains solve such challenging tasks might allow us to identify the minimal neural circuitry required for complex problem solving.’

The team used artificial flowers to test whether bees would follow a route defined by the order in which they discovered the flowers or if they would find the shortest route. After exploring the location of the flowers, bees quickly learnt to fly the shortest route.

As well as enhancing scientists’ understanding of how bees move – pollinating crops and wild flowers – the research has other applications.

Human beings rely on traffic networks, computer networks and business supply chains; by gaining an understanding of how bees can solve their problem with such a tiny brain, researchers hope to be able to understand how they might be able to optimise the management of such networks without needing a lot of computer time.

Queen Mary researcher Dr Mathieu Lihoreau said: ’There is a common perception that smaller brains constrain animals to be simple reflex machines. But our work with bees shows advanced cognitive capacities with very limited neuron numbers.’