Begging Beetles Fool Honeybees for Food

Beetles kept as prisoners in honeybee hives trick their captors into feeding them.

One of Earth's most intriguing arms races doesn't take place on the international stage, but instead goes on in the cozy confines of beehives. Small hive beetles (Aethina tumida) commonly reproduce in the nests of honeybees, and feed on pollen, honey, and even larvae. In defense, honeybees imprison the pests in cells partly sealed by tree sap and guarded by worker bees. Now, new research shows that incarcerated beetles fight back by pretending to be part of the family.

James Ellis from Rhodes University, South Africa, and colleagues rigged an infested honeybee hive with a camera to watch beetle-bee interactions. They found that jailed beetles that properly touched the antennae of their guards - the way a colony member would - received a regurgitated meal. Meal-sharing is common amongst social insects such as bees, ants, and wasps. In this way, begging beetles are able to stave off starvation while incarcerated.

Native to South Africa, small hive beetles were accidentally introduced in 1998 to the southeastern United States, where they have quickly spread and are spoiling beekeepers' colonies. Although pervasive in South African hives, the beetles do not pose a problem. While the exotic beetles seem to be pulling ahead of native bees in the U.S., Ellis and his team are working to nip this particular arms race in the bud. The researchers are currently investigating the natural factors keeping the beetles in check in their homeland to come up with like strategies to control infestations in the U.S.

A marked honeybee, Apis mellifera, guards a beetle prisoner confined to a cell made of propolis, tree saps mixed with bees' secretions. Photo: James Ellis.

This honeybee guard has been tricked into feeding its beetle prisoner. Photo: James Ellis.

Beetle prisoners are suspended between angry worker bee guards. However, one beetle has managed to trick its guard into providing a free meal (the beetle getting fed is the one attached at the mouth to one of the honeybees on the bottom row of bees.)
Photo: James Ellis.