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Alien Invasion

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Dr. Killer Bee 4 pages: | 1 | 2 | 3 | 4 |

Why are people allergic to bees?

Some other animals are, too. There seems to be a disproportionate frequency of allergy to stings. Why is that? We don't go into shock over most things.

For a beekeeper, the size difference makes the toxicity trivial. But if you are a mouse, four to five stings could kill you.

We don't have an answer, but here's something to think about: could it be that selection has worked on venom to be allergenic? This strategy could work well against intelligent social animals such as monkeys and people. If one member of the family or group gets stung and the others watch as that member has an anaphylactic reaction and possibly dies, that would really send a message!

Whether this hyperallergenicity occurred by natural selection or a weird coincidence we have no idea, but it's fun to think about.

How are "killer bees" different from regular honeybees?

Photo of Swarm of Bees
Schmidt theorizes that these bees evolved aggressive tendencies to defend their hives from early honey-hunters in Africa.

Killer bees evolved different behavior. They didn't have to change their chemistry or change their morphology. They don't use more venom. They are just really aggressive. We're largely immune to the lethal potential of honeybee venom; so, we're not worried about an odd bee sting. But killer bees send 10 thousand to 15 thousand bees out. If you play with these odds, you are not going to get out of there alive. It's more or less a proportional relationship to the mouse's story. Killer bees take the truth in advertising idea and square it.

How are killer bees related to our honeybees?

Ten of the eleven species of bees evolved in Asia. The other one- ours- evolved in Africa, and it broke into races. Several of the races broke out of Africa and into Europe- just as human ancestors came out of Africa.

The bees who went north found that there were six to eight months with no food and that it's pretty cold. So they evolved to store more food in the form of honey and build better, more permanent nests. These are the bees Europeans brought here. But just like not all people left Africa, not all bees did either.

Killer bees send 10 to 15 thousand bees out. If you play with these odds, you are not going to get out of there alive.

People have a strong sweet tooth and people in Africa became honey hunters, I'd say- and there's not solid evidence for this- at least a million years ago. Long before fire, as people started getting smarter and figured out more clever ways to steal it, the two species began to co-evolve. It was an arms race; as the honey hunters got smarter, the bees got nastier. Then we got fire. With this new tool to intimidate bees, the war really escalated and we got super-defensive bees.

When we brought these African bees to the New World, we had a mixing of African and European bees and the progeny retained more African traits.

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4 pages: | 1 | 2 | 3 | 4 |

Photos: Justin O. Schmidt

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