Stressed bees are more likely to make negative choices, scientists say. — AFP
Humans aren’t the only animals to get stressed.
In fact, bumblebees also show physical reactions to stress. According to a British research published in the journal Proceedings of the Royal Society B, these insects are significantly more pessimistic when faced with a stressful situation.
A research team from Newcastle University (UK) has studied the behaviour of bumblebees under stress.
To do this, they taught these flying insects to associate two colours with different types of reward, in the form of more or less sweet drinks.
The sweeter beverage was in a room where the colour blue was projected on a screen, and the less sweet one was in another room associated with green.
With practice, the bumblebees systematically went to the room where they could enjoy the sweetest drink.
Once this learning phase was complete, the researchers divided the bumblebees into three groups, one of which was a control group.
Members of the first two groups were placed in stressful situations, unlike those in the control group.
All the bumblebees were then invited to go to one of the two rooms to which they had access, based on the colour they saw on a screen (blue, green but also more ambiguous colours).
More pessimistic
It turns out that the bees that had been subjected to stress were more pessimistic than others.
They were less inclined to interpret ambiguous colours as potentially promising. In other words, they tended to go to the room with the least sweet reward.
Bumblebees in the control group, which had not been exposed to stress, were far more optimistic in their choices.
“Our research suggests that, like other animals including humans, bees may experience emotion-like states when stressed, as demonstrated by a clear shift towards pessimism. When faced with ambiguity, stressed bees, much like someone seeing the glass as ‘half empty,’ are more likely to expect negative outcomes,” says study coauthor Dr Olga Procenko, quoted in a news release.
Although this study was carried out under laboratory conditions, the researchers believe their findings suggest that bumblebees may react differently to flowers if they are stressed. This could affect their role as pollinators.
However, the effect of stress on bumblebee cognition and behaviour needs to be studied further in the future for the scientific community to truly understand its full impact on these insects. – AFP Relaxnews
