How do you visit multiple places via the shortest possible route? This is the question posed by the classic traveling salesman problem, something that without our beloved satnavs and GPS, we find pretty tricky to accomplish. But now it seems that bumblebees can solve this complex mathematical problem, all by themselves.
The traveling salesman problem asks: "Given a list of cities and the distances between each pair of cities, what is the shortest possible route that visits each city and returns to the origin city?"
Now, while bumblebees aren’t exactly journeying from city to city, they do need to get from flower to flower as efficiently as possible. So researchers from Rothamsted Research in Harpenden in the UK decided to test whether bees and traveling salesmen have something in common. And according to their findings published in Scientific Reports, they do.
Instead of cities to visit, the bumblebees were given artificial flower feeding stations to make their way between. The team tried to trick the bees with shortcuts, tempting the insects to follow routes that increased short-term gain, but actually lengthened the overall journey from feeder to feeder.
At first, the bees fell for the researchers’ tricks. But, as time went on, the bumblebees managed to perfect their routes to avoid the shortcuts, minimizing their overall journeys and ending up with the most efficient flight path possible. Hence, they solved the traveling salesman conundrum. Not bad when your brain is just 0.0002 percent the size of a human’s.
To reach their conclusion, the researchers employed six bees and a special kind of radar. This radar was able to identify signature reflections produced by minuscule transponders attached to the bees. From this information, the team could create animated heat maps of where the insects were flying. They made 201 flights in total.
“We tracked every single foraging flight that the bees undertook as they learned about the feeder array, with the radar telling us the position of the bee every three seconds, to an accuracy of two metres,” lead author Joe Woodgate, from Queen Mary University of London, told New Scientist.
“Animals cannot inspect a map to find out where the best food sources are or plan how to get to them; instead, they must explore the landscape, discovering locations one by one, and then they face the challenge of integrating their spatial memories into an efficient route.”
The team believes its findings could be used in the development of artificial intelligence and advanced robots. But more importantly, better understanding bumblebees could help us save them – pollinators are responsible for around 35 percent of the crops we rely on, and we are losing them at an alarming rate.
[H/T: New Scientist]