Bees similar to people

CYNTHIA RAMSAY

There are at least two reasons for humans to care about bees: their decision-making processes are similar to ours and about a third of our diet depends on them.

Dr. Sharoni Shafir will discuss these issues and others when he is in Vancouver in September for the Stretch Your Mind Series hosted by Vancouver's Canadian Friends of Hebrew University.

Shafir is the director of the B. Triwaks Bee Research Centre and the head of the department of entomology at the Hebrew University of Jerusalem's Robert H. Smith Faculty of Agriculture, Food and Environment in Rehovot. His research areas include animal cognition, behavioral ecology and pollination ecology, but he told the Independent that he's particularly interested in bees because of their decision-making processes.

Shafir said that the reason often given for people's poor decisions is that "we're kind of messed up, we live in a very artificial world, we have all these psychological problems and that's why we do all these foolish things. Animals should know better, because they've been around for longer, they've [been naturally] selected to do it right and so forth, but when I've tested these kinds of questions on bees, I found that bees were doing the same things that humans were doing." He said that, for example, you can frame questions to make bees do a certain thing, as advertisers try to influence consumers to make certain choices.

"There are a few studies that we do that we see that bees behave very similarly to humans in their decision-making patterns," he explained, adding, "The trick really is to be able to talk to the bees." He elaborated on one method of doing this: "Basically, bee after bee comes into the turning station and she gets a puff of odor and one puff of odor comes from the right and a different puff of odor comes from the left and bees, as you can imagine, are very good at discriminating odors.... Also, they're very quick learners, and that's what makes them such an ideal model for studying memory and learning and decision-making. So, what we teach them ... is that if they choose the right side, the odor on the right, they always get the small reward and if they choose the odor on the left, sometimes they get a high reward and then they're happy and sometimes they get nothing. For experience, we give them a few trials and they learn to associate the two distributions of rewards and then we ask them, OK, now you choose: you have this odor here and this odor there, which one would you prefer? You want to go for the sure thing or you want to go for the gamble? Then we see where they point their head and stick out their tongue and they point at the side that they want and then they get that reward."

In the outside world, the choices bees make are crucial for humans.

"Everybody knows that bees give honey and bees sting, but that's kind of the side effect," he said. "What they really do for us is give us about a third of our diet. Actually, for a rich country in the Western world, it's probably even more than a third. Apples, avocado, almonds, pears, peaches, many other fruits and vegetables are pollinated by bees. Also, if you eat meat ... to feed the cows, you give them the alfalfa and, to pollinate the alfalfa seeds to get more alfalfa, you need bees."

Shafir explained that bees can fly a radius of several kilometres and, along their way, they decide which crops appeal to them. He gave the example of avocados, which, he said, bees don't like that much, so it matters what else is planted or grows in their vicinity.

"It's all a matter of competition," he explained. "A lot of this work is joint between biologists and economists because we're looking at similar questions of competition, competing markets.... As soon as some nice wildflowers flower are nearby or citrus flowers are nearby, they'll [the bees will] dump the avocado and all go somewhere else."

Honeybees are the most important pollinators, said Shafir, because of their social nature. "When I bring a colony of honey bees," he said, "I bring several thousand workers, while there are other bees, that are solitary, [and] when you bring them, you only bring a few workers."

The reason the honeybees are so successful and the interesting part about their decision-making, he said, is that there are individual bees making individual decisions, but the whole colony also has colony-level decisions. "If one bee flies two kilometres somewhere and finds something nice blooming, she comes back and she communicates what's she's found to her nest mates through the bee dance and then other bees go there and they come and dance," said Shafir. "Within a few minutes, you get all your bees that were, say, on the avocado, they ... all go to the other source."

The dance is another way to look into the minds of bees, he said, once more using avocado as an example: bees have a less vigorous dance for an avocado than a citrus source. Even if bees find two sources equal in nutrient value, if one doesn't taste good to them, they say, by their dance, don't go there. "This is on the verge between biology and psychology," said Shafir, who said that scientists are beginning to find out which minerals taste good to bees. In the case of avocado, this means trying to reduce the amount of certain minerals in the nectar, he explained. "Through selection or genetic engineering, you could try to raise cultivars of avocado that are going to have nectar that'll be more tasty to the bees."

The worldwide decrease in bee populations, or "colony collapse disorder," is complex and the reasons for it are not clear, said Shafir. If you had bees dying from pesticide use and there were many dead bees around, it would be easy to determine their cause of death, he explained. "Here, it's something where the bees are disappearing from the hives and it's not clear exactly what's happened."

The hypothesis he and a team of HU scientists are working on is "based on a study that showed a very strong correlation between this disorder and the existence in the hive of a particular virus that happens to be called the Israeli acute paralysis virus, IAPV. It was first given the name at the faculty of agriculture at the Hebrew University a few years ago before the syndrome was even known. We had some bees here and this virus was discovered to be new ... but it's a virus that's all over the world. In the United States, it's been strongly correlated with colony collapse disorder, but the story is probably more complex. If you just had the virus, you'd die from the virus, but here, the bees are disappearing, so we're working on different hypotheses of how this virus is affecting the bee behavior to cause them to not be able to navigate correctly and get lost." Shafir noted that there is commercial research being done to develop something that would make the bees immune to the virus.

For more on Stretch Your Mind, visit cfhu.org/node/678.

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