Glass is Half Empty to Shaken Honey Bees


When people are depressed or anxious, they tend to see their glass as half empty, not half full — but who would expect  the same to hold true of honey bees? New research out of Newcastle University has shown for the first time that bees, when agitated as they would be when disturbed by a predator, show similar signs of pessimism.

To find out something about how honeybees view the world, the researchers “set them up to make a decision about whether an unfamiliar scent portended good or bad things.”

First, the bees were trained to connect one odour with a sweet reward and another with the bitter taste of quinine. The bees learned the difference between the odours and became more likely to extend their mouthparts to the odour predicting sugar than the one predicting quinine.

Next, the Institute of Neuroscience researchers divided the bees into two groups. One group was shaken violently for one minute to simulate an assault on the hive by a predator such as a honey badger. The other group was left undisturbed. Those bees were then presented with the familiar odours and some new ones created from mixes of the two.

Agitated bees were less likely than the controls to extend their mouthparts to the odour predicting quinine and similar novel odours, they found. In other words, the agitated bees behaved as if they had an increased expectation of a bitter taste, the researchers said, demonstrating a type of pessimistic judgement of the world known as a ‘cognitive bias.’

While it may be too soon to claim that honeybees experience “emotions” the way that we humans do, this seems not to be as big a stretch as once we might have imagined!

“What we have shown is that when a honeybee is subjected to a manipulation of its state that in humans would induce a feeling of anxiety, the bees show a similar suite of changes in physiology, cognition and behaviour to those we would measure in an anxious human,” said Dr Geraldine Wright, one of the study’s authors. “In terms of what we are able to measure, a shaken honeybees is no less ‘anxious’ than a lonely dog or a rat in a barren cage.”

For more information, see also:

Agitated Honeybees Exhibit Pessimistic Cognitive Biases
Melissa Bateson, Suzanne Desire, Sarah E. Gartside, Geraldine A. Wright
Current Biology – 2 June 2011 (Vol. 21, Issue 12, pp. 1070-1073)

For stressed bees, the glass is half empty
Newcastle University: Biomedicine: News – 3 June 2011

Photo:  Baukette aus Bienen by Maja Dumat on Flickr