Researchers have captured high-speed video of a honey bee stinger continuing to pump venom after the bee has flown away, revealing that the detached stinger works as a double-piston pump. The study, published in the Proceedings of the National Academy of Sciences, is the first to directly observe the pumping mechanism in action.
Honey bees (Apis mellifera) are unusual among venomous insects because worker bees leave their barbed stingers embedded in the target's flesh and fly away. The stinger keeps penetrating the tissue and pumping venom on its own, a rare phenomenon known as autotomy. While the outcome has long been familiar to anyone stung by a bee, the precise mechanism behind it had never been directly observed.
The stinger consists of three interlocking elements that form the venom canal: a stylet that widens to form the main pumping chamber, and two sharp-tipped lancets that slide back and forth. The footage shows the lancets working together to pierce tissue and drive venom into the wound, operating like a double piston.
The paper also sets the honey bee alongside other venom-delivery strategies. Spiders contract muscles around their venom glands to eject venom through hollow fangs, while bees, wasps and ants deliver venom through stingers, either by contracting muscles around the venom reservoir or through the stiff lancets themselves. The honey bee's self-operating stinger, the authors report, adds a unique mechanism to that list.