Stingless Suicide: Bees Biting Till They Die

An angry swarm of bees has always sounded scary, but what about an angry suicidal swarm of biting bees? Now that sounds like pure terror. A new study of Brazilian stingless bees has found that to defend their homes, these little guys will latch onto a threat and won't stop biting until they die.

The study, recently published in the journal Behavioral Ecology and Sociobiology (BES), details how the tropical stingless bee Trigona hyalinata appears to have adapted a berserk self-sacrificial form of defense for the hive, in which they will abandon all caution and never let go of a threat once they've bitten it with their tiny 10-toothed mandibles.

Of course, these are not the only insects that will sacrifice themselves for the greater good of the colony. An ant from Madagascar, the Malagidris sofina, has been observed to actually throw itself off cliffs with potential invaders, and honeybees will actually inflect lethal injuries upon themselves to embed their stinger into a threat to the hive.

However, while both these insects boast special adaptations to help their reckless defenses be effective, T. hyalinata is actually very ill-equipped for combat, with a tiny black body, and no threatening stinger to speak of.

According to the BES study, in an assessment of 12 stingless bee species, researchers found that three Trigona species were the most successful at defending their hives, even when their bites are far less painful than a honeybee sting.

"I have been stung by honeybees over 10,000 times, so am pretty hardened to the pain," researcher Francis Ratnieks, also of the University of Sussex, explained to New Scientist.

He says he can now just shrug these stings off. However, in the case of Trigona, "when dozens of them start biting you, you have to retreat. It's not nice at all."

The secret, Ratnieks and his colleagues suggest, is in the bees' aggression, where their berserk biting can mean that you will have to crush them to make the pain stop.

T. hyalinata in particular was found to be particularly suicidal, with 83 percent of attacking individuals continuing to bite until they suffered irreparable harm. Even then, their little heads might mindlessly keep biting, much like when you kill a spider and its legs keep twitching.

Creepy? Yes. Terrifying? Absolutely. But, as the researchers found, it's also an incredibly powerful deterrent, no stings required.