A bumblebee’s brain is roughly the size of a sesame seed, which makes the latest findings from a team of neuroscientists at Macquarie University all the more remarkable. Published in the journal Science, the study found that bumblebees have a genuine sense of rhythm, making them the first small-brained insect ever shown to possess this ability. The researchers trained bees to associate specific flashing light patterns with a sugar water reward, with one pattern meaning food and another meaning nothing. The bees learned the difference reliably. Then the scientists changed the tempo, speeding the patterns up and slowing them down, and the bees still recognized which was which. The lead researcher compared it to hearing a familiar song played at a different speed and still knowing exactly what it is, because you have grasped the overall structure rather than memorized a single detail.
The team pushed further. They built a maze where a vibrating floor pulsed in different rhythms at a junction, with one beat meaning turn left and the other meaning turn right. The bees learned to navigate by the beat alone. Exactly how they manage this with such a tiny nervous system remains unknown, but the researchers believe that rhythm recognition may have deep evolutionary roots connected to the complex patterns bees encounter constantly in their natural world. Bumblebees have already surprised scientists by demonstrating basic arithmetic, an understanding of the concept of zero, an ability to form mental images and what appears to be a genuine fondness for playing with toys. The practical implications of this latest finding may extend beyond bee biology: the researchers suggest the discovery could help guide the development of tiny sensors capable of detecting rhythmic patterns in applications ranging from music recognition to monitoring heart irregularities and brain activity.
