An international team of researchers from Jiangnan University, China, Queen Mary University of London, and the University of Oulu, Finland, have recently discovered that a specific type of gut bacteria (Lactobacillus apis) is linked to enhanced memory in bumblebees. This study adds to the growing scientific evidence that the gut microbiome, consisting of trillions of microbes living in our intestines, can affect animal cognition and behavior.
Since bees have a relatively small community of gut microbes compared to mammals, they are ideal models to explore the role of specific gut bacteria on differences in cognition and behavior between individuals.
In order to test bees’ memory and learning abilities, the researchers created different colored artificial flowers, some of them associated with a sweet sucrose solution, and others with a bitter tasting solution containing quinine, which is a repellent for bees. Afterwards, they assessed how quickly the bees managed to learn which colors are associated with a sugar reward, and whether they were able to remember this information three days later.
By sequencing gut samples from the bees, the scientists compared individual differences in learning and memory abilities with the levels of different gut microorganisms. They found that bumblebees with more Lactobacillus apis in their microbiome had a better memory and stronger learning abilities than those with fewer bacteria.
Furthermore, to confirm that the numbers of Lactobacillus apis were directly responsible for the differences in learning and memory, the researchers added these bacteria to the bumblebees’ diet and measured their responses to the same task.
“Our results suggest not only that the natural variation in the amount of a specific gut bacterium effects memory, but also show a causal link – that by adding the same bacterial species to a bee’s diet can enhance their memories,” said study lead author Dr. Li Li, a postdoctoral fellow at Jiangnan University.
“This is a fascinating finding that could apply to humans as well as to bees. Our findings add to growing evidence of the importance of gut-brain interactions in animals and provide insights into the cause of cognitive differences in natural bumblebee populations,” added study co-author Lars Chittka, a professor of Zoology at Queen Mary University.
This study, published in the journal Nature Communications, shows that we can improve our cognitive abilities by regulating gut microbiota.