Honey bees study finds that insects have personality too

Mar 08, 2012
New research indicates that individual honey bees differ in personality traits such as novelty-seeking. Credit: L. Brian Stauffer

A new study in Science suggests that thrill-seeking is not limited to humans and other vertebrates. Some honey bees, too, are more likely than others to seek adventure. The brains of these novelty-seeking bees exhibit distinct patterns of gene activity in molecular pathways known to be associated with thrill-seeking in humans, researchers report.

The findings offer a new window on the inner life of the hive, which once was viewed as a highly regimented colony of seemingly interchangeable workers taking on a few specific roles (nurse or forager, for example) to serve their queen. Now it appears that individual honey bees actually differ in their desire or to perform particular tasks, said University of Illinois entomology professor and Institute for Genomic Biology director Gene Robinson, who led the study. These differences may be due, in part, to variability in the bees' , he said. The study team also included researchers from Wellesley College and Cornell University.

"In humans, differences in novelty-seeking are a component of personality," he said. "Could insects also have personalities?"

Robinson and his colleagues studied two behaviors that looked like novelty-seeking in honey bees: scouting for nest sites and scouting for food.

When a colony of bees outgrows its living quarters, the hive divides and the swarm must find a suitable new home. At this moment of crisis, a few intrepid bees – less than 5 percent of the swarm – take off to hunt for a hive. These bees, called nest scouts, are on average 3.4 times more likely than their peers to also become food scouts, the researchers found.

"There is a gold standard for personality research and that is if you show the same tendency in different contexts, then that can be called a personality trait," Robinson said. Not only do certain bees exhibit signs of novelty-seeking, he said, but their willingness or eagerness to "go the extra mile" can be vital to the life of the hive.

The researchers wanted to determine the molecular basis for these differences in honey bee behavior. They used whole-genome microarray analysis to look for differences in the activity of thousands of genes in the brains of scouts and non-scouts.

"People are trying to understand what is the basis of novelty-seeking behavior in humans and in animals," Robinson said. "And a lot of the thinking has to do with the relationship between how the (brain's) reward system is engaged in response to some experience."

The researchers found thousands of distinct differences in in the brains of scouting and non-scouting bees.

"We expected to find some, but the magnitude of the differences was surprising given that both scouts and non-scouts are foragers," Robinson said.

Among the many differentially expressed genes were several related to catecholamine, glutamate and gamma-aminobutyric acid (GABA) signaling, and the researchers zeroed in on these because they are involved in regulating novelty-seeking and responding to reward in .

To test whether the changes in brain signaling caused the novelty-seeking, the researchers subjected groups of bees to treatments that would increase or inhibit these chemicals in the brain. Two treatments (with glutamate and octopamine) increased scouting in bees that had not scouted before. Blocking dopamine signaling decreased scouting behavior, the researchers found.

"Our results say that novelty-seeking in humans and other vertebrates has parallels in an insect," Robinson said. "One can see the same sort of consistent behavioral differences and molecular underpinnings."

The findings also suggest that , humans and other animals made use of the same genetic "toolkit" in the evolution of behavior, Robinson said. The tools in the toolkit – genes encoding certain – may play a role in the same types of behaviors, but each species has adapted them in its own, distinctive way.

"It looks like the same molecular pathways have been engaged repeatedly in evolution to give rise to individual differences in novelty-seeking," he said.

Explore further: Research helps steer mites from bees

More information: "Molecular Determinants of Scouting Behavior in Honeybees," Science (2012).

Related Stories

Paper wasps and honey bees share a genetic toolkit

Apr 27, 2010

They are both nest-building social insects, but paper wasps and honey bees organize their colonies in very different ways. In a new study, researchers report that despite their differences, these insects rely on the same ...

Honey bee genome holds clues to social behavior

Oct 23, 2006

By studying the humble honey bee, researchers at the University of Illinois at Urbana-Champaign have come a step closer to understanding the molecular basis of social behavior in humans.

Honey-bee aggression study suggests nurture alters nature

Aug 17, 2009

A new study reveals that changes in gene expression in the brain of the honey bee in response to an immediate threat have much in common with more long-term and even evolutionary differences in honey-bee aggression. ...

Recommended for you

Research helps steer mites from bees

7 hours ago

A Simon Fraser University chemistry professor has found a way to sway mites from their damaging effects on bees that care and feed the all-important queen bee.

Bird brains more precise than humans'

8 hours ago

(Phys.org) —Birds have been found to display superior judgement of their body width compared to humans, in research to help design autonomous aircraft navigation systems.

User comments : 0