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Why do honeybees die when they sting?

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Colonies of bees have been disappearing since 2006. Photo by Flickr user Andreas

It is only the female honeybees, or the worker bees, that sting. Photo by Flickr user Andreas

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Why do honeybees die when they sting?

When a honeybee stings, it dies a gruesome death. The bee’s stinger is structured in such a way that once it punctures human skin, the bee can’t yank it out without self-amputating. As the honeybee tries to pull out the stinger, it ruptures its lower abdomen, leaving the stinger embedded, pulling out instead a string of digestive material, muscles, glands and a venom sac. What results is a gaping hole at the end of the abdomen.

Bee sting

“It’s kind of like bleeding to death, except bees don’t have blood,” said Eric Mussen of the University of Davis. Mussen is an apiculturist, a fancy word for beekeeper. “It’s fake, clear insect blood.”

The honeybee stinger is hollow and pointed, like a hypodermic needle, Mussen said. It contains two rows of lancets, or saw-toothed blades. These blades are barbed in shape, and face outward like a harpoon.

 A honeybee stinger magnified 650x, from Rose-Lynn Fisher's book, BEE. Image by Rose-Lynn Fisher

A honeybee stinger magnified 650x, from Rose-Lynn Fisher’s book, BEE. Image by Rose-Lynn Fisher

As a bee stings, the blades alternate, “scissoring together into your flesh,” said Mark Winston, biologist and author of “Bee Time: Lessons from the Hive.” It looks — and works — like a screw anchor, meaning that once in, the stinger can’t retract. Muscles connect the stinger to a venom sac, from which a cell-destroying toxin is pumped into the hole.

Bee screw copy

The scent of the venom released from the honeybee signals a threat to the hive. And weirdly, it smells like bananas. That’s because the “alarm pheromone” of honeybees contains isopentyl acetate – which is potassium.

But lets back up. It is only the female honeybees, also known as the worker bees, that sting. Each hive contains some 60,000 worker bees, followed by a few hundred male drones and a single female queen bee.

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Worker bees are like disposable soldiers for the colony: their sole function is to gather nectar, pollinate, and defend the base. They are all infertile females. The queen lays all eggs and the drones fertilize them.

The queen bee only stings when fighting for dominance against another queen, Winston said.

And while the hornet and the wasp are known for being more aggressive, honeybees are more docile, and typically only attack when threatened.

“A wasp or a bumblebee can sting again and again, but the honeybee only gets you once, and it’ll get you good,” Mussen said.

The post Why do honeybees die when they sting? appeared first on PBS NewsHour.


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