When we feel depressed and anxious, we tend to take a pessimistic view of life and our decisions reflect that negative emotional state. Other animal species also show the “glass half empty” attitude when they are teed-off by their treatment.
Dogs, horse and birds have all been shown to show a pessimistic cognitive bias when they are anxious. The big question, then, is how universal is pessimism when you’re not too happy with your situation? Wright et al at Newcastle U set out to answer that with some diligent workers (1).
They selected some honeybees, cooled them down and fitted them out in little plastic straightjackets. Then the training began. They were given an odor to sniff and then offered a drink. One drink was a reward in the form of a sucrose solution. The other odor they were taught to associate with punishment as the drink was a nasty, bitter quinine solution. Little tongues were retracted as soon as they smelt the odor representing quinine.
Now they were ready for the great experiment. They were divided up into two groups. One group were strapped to a laboratory shaker and the bejesus shaken out of them for a minute, while the other group were used as the control. Next they were all asked to sniff 5 odors, 3 of which were new. The anxious, shaken up group were reluctant to stick their tongues out for anything but sucrose. They weren’t going to trust those lab guys. But the unshaken group weren’t stirred up. They were much more adventurous and little tongues were stuck out to try the new drinks. Clearly not expecting punishment and seeing the world as a “glass half full.”
The experiment didn’t end well for any of the participating workers, though their expectations weren’t recorded. They all went into the meat grinder and had their hemolymph (the nearest thing that they’ve got to blood) analyzed. The shaken up ones had lower levels of those hormonal indicators of positive thinking, dopamine and serotonin, than the “happy” group had.
One is left to wonder how pessimistic the colony gets when they are just hunkering down for winter and we snatch nearly all their hard worked for stores and offer them a bland sugar solution as wages?
- M.Bateson, S.Desire, S.E.Gartside and G.A.Wright, J.Curr. Biol., 21, 1070, (2011).
