An insect dubbed the Dracula ant is a speed champion among animals: it snaps its front pincers shut in less than 1/5,000 of the time it takes to blink.
Trap-jaw ants (Odontomachus), mantis shrimp and other creatures have evolved appendages that move with lightning swiftness. These species achieve high speeds using a spring-loaded system similar to a catapult. But Dracula ants — in the genus Mystrium, and so called because they sometimes feed on the blood of their young — press their two front pincers together before slipping them past each other like a finger snap.
Fredrick Larabee at the National Museum of Natural History in Washington, DC, and colleagues investigated this mechanism using computer models and high-speed videos. The researchers found that the ant’s front appendages, unlike those of most other ants, can bow inwards when the pincer tips press against each other, generating a spring-like tension. When one pincer slips under the other, this tension releases, propelling the pincers shut at 90 metres per second — faster than a bullet train, and the fastest-known speed for an animal appendage.