Dec. 28 (UPI) -- The biggest bumblebees use "learning flights" to memorize the locations of the best flowers, according to new research.
Scientists found smaller bumblebees were less selective.
Researchers already knew bumblebees perform learning flights, turning to look back from different angles as they depart a flower, after collecting nectar.
For the new study, published Monday in the journal Current Biology, scientists looked at how learning flight behavior differs among big and small bumblebees.
"It might not be widely known that pollinating insects learn and develop individual flower preferences, but in fact bumblebees are selective," study co-author Natalie Hempel de Ibarra said in a news release.
"On leaving a flower, they can actively decide how much effort to put into remembering its location," said Hempel de Ibarra, an associate professor at Exeter University's Center for Research in Animal Behavior.
Using artificial flowers filled with different concentrations of nectar, researchers revealed differences in the ways bigger and smaller bumblebees go about forming and remembering flower preferences.
For the experiment, researchers presented bumblebees in greenhouses with plots of artificial flowers, each filled with solutions containing varying concentrations of sucrose.
Observations showed larger bumblebees altered their learning flight behavior based on the sweetness of a flower's nectar reserves.
Bigger bumblebees spent more time learning the location of the flowers with the richest sucrose concentrations. Conversely, smaller bumblebees performed the same learning flights for each flower.
"The differences we found reflect the different roles of bees in their colonies," said Hempel de Ibarra.
"Large bumblebees can carry larger loads and explore further from the nest than smaller ones. Small ones with a smaller flight range and carrying capacity cannot afford to be as selective, so they accept a wider range of flowers," she said.
According to the study's authors, smaller bees tend to be more heavily involved in work inside the hive, foraging only when there is an especially high need for food and reserves are running low.