Although most people assume a jellyfish sting is an allergic reaction to an irritant on the surface of the creature's tentacles, it is actually caused by microscopic cells that work like a syringe, puncturing the surface of the skin and almost instantaneously injecting venom before retracting.
Destin Sandlin, founder and host of YouTube channel SmarterEveryDay, took his cameras to James Cook University in Australia, where Dr. James Seymour used a microscope and high-speed lens to record the first ever video of the jellyfish stingers in action.
"We've never seen that before," Seymour exclaims upon observing the delay between when the needles were deployed and the venom was injected.
"We've seen venom come out the end of these things, [but] we've never seen that delay [between deployment and injection] -- but we've never looked for it ... This is the sort of stuff I get up in the morning for ... It's the joy of actually coming in and going 'I just saw something that nobody else in the world has ever seen before.'"