Big Bumblebees Take Time to Memorize Locations of Best Flowers; Big Bumblebees Have Longer Flight Range and Higher Carrying Capacity Than Smaller Bumblebees, Which Do Not Alter Their Location Learning Efforts on Basis of Flower’s Nectar Richness

Big bumblebees take time to learn the locations of the best flowers, new research shows. Meanwhile, smaller bumblebees--which have a shorter flight range and less carrying capacity--don't pay special attention to flowers with the richest nectar. University of Exeter (UK) scientists examined the "learning flights" which most bees perform after leaving flowers. Honeybees are known to perform such flights-- and the study shows bumblebees do the same, repeatedly looking back to memorize a flower's location. "It might not be widely known that pollinating insects learn and develop individual flower preferences, but, in fact, bumblebees are selective," said Natalie Hempel de Ibarra, PhD, Associate Professor of Neuroethology at Exeter's Centre for Research in Animal Behavior (https://psychology.exeter.ac.uk/staff/profile/index.php?web_id=Natalie_Hempel_de_Ibarra). "On leaving a flower, they can actively decide how much effort to put into remembering its location. The surprising finding of our study is that a bee's size determines this decision-making and the learning behavior." In the study, captive bees visited artificial flowers containing sucrose (sugar) solution of varying concentrations. The larger the bee, the more its learning behavior varied depending on the richness of the sucrose solution. Smaller bees invested the same amount of effort in learning the locations of the artificial flowers, regardless of whether sucrose concentration was high or low. "The differences we found reflect the different roles of bees in their colonies," said Professor Hempel de Ibarra. "Large bumblebees can carry larger loads and explore further from the nest than smaller ones.