Buzzing with theories

Earlier this year the United Nations Environmental Programme (Unep) released a report indicating that bee populations around the world had declined significantly, in some places by as much as 85 percent. The disappearance of these insects is a problem because, as the Unep report noted: “out of some 100 crop species which provide 90 percent of food worldwide, 71 of these are bee-pollinated…. The production value of one ton of pollinator-dependent crop is approximately five times higher than one of those crop categories that do not depend on insects.”

The Unep report includes a number of factors that might be contributing to the drop in bee populations, such as parasites, pollution, climate change and habitat destruction. One factor they don’t mention, however, is the effect of cell phones on bees, an association that has been making the rounds in recent weeks. While the Unep report does note that bees seem to be influenced by magnetic and electrical fields, the authors noted that there was insufficient data to make any associations.

Cell phones’ effects

One of the studies being cited in the stories about the effects of cell phones on bees comes from India’s Pubjab University and first appeared in the journal Toxicology International back in January. Zoologists exposed two groups of honeybees to activated cell phones of the same make and model that were connected to the same cellular network. A third group of bees was kept away from any cell phones and served as the experimental control.

One phone was set on “call” mode with a recorded message simulating an active conversation while the other was on but not in use. The team led by Pooja Badotra took samples from honeybees in each group at three different time points to see if the cell phones were having any effect on the insects’ biochemistry.

They found that the glucose and carbohydrate levels in the bees exposed to the cell phones were higher than the levels of the bees in the control group, suggesting they said, that the bees were being stressed by the devices. The study was not done over a long enough period of time, however, to see if the cell phones stressed the bees enough to make them leave the area.

Dropping populations

If reading about the Unep report and the reports linking dropping bee populations with cell phone usage is changing your mood, consider how the bees feel. According to researchers at Newcastle University in the United Kingdom, the insects can get moody, information that could be useful for those studying the biochemistry of emotions.

“If some scientific research on emotion could be conducted in insects, this would lead to a reduction in the numbers of sentient vertebrate animals used in research,” said Melissa Bateson, first author of the study that appeared in the journal Current Biology the week of June 2. “Thus our research potentially has important implications for animal welfare.”

Bateson and her colleagues first trained bees to recognize two scents: one that indicated a sweet treat and one that didn’t. Then some of the trained bees were stressed after researchers simulated an attack on them by a predator by literally shaking them up.

Afterward, when they were exposed to the two scents once more, the researchers found that the shaken bees were less likely to react to the scent of the less-sweet treat than were the bees in the control group. The reaction, Bateson and her colleagues said, suggests that the bees have gained a more negative view of the world as a result of the attack, which would suggest that the insects can express anxiety like humans, cats and dogs.

“We have shown that the emotional responses of bees to an aversive event are more similar to those of humans than previously thought,” said Bateson’s mentor and the study senior author Geraldine Wright. “Bees stressed by a simulated predator attack exhibit pessimism mirroring that seen in depressed and anxious people.”

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