You’d think that spring-loaded hypodermic needles filled with venom would be something only found in one of the SAW films, but the stinging tentacles of jellyfish have had that gruesome contraption for millions of years.
A jelly’s stinging cells — called nematocytes — work on a hair trigger. When something bumps up against these specialized cells, that trigger is tripped, and the machinery inside launches out in milliseconds. It’s like a supersonic harpoon attached to a hose filled with venom. You can find videos of nemtocytes firing, and they are incredible to watch, but they don’t really have the resolution to illuminate what is going on. What you need is some patience and some really good video equipment.
YouTube science show Smarter Every Day has done just that. Using a high-end Phantom camera and a microscope, host Destin and toxinologist Dr. Jamie Seymour have captured an unprecedented view of these stinging cells firing. It’s fascinating and oddly beautiful, but it’s not just for show. Take a look:
Without being able to slow everything down, you can still figure out the machinery involved in a jellyfish sting. What the Phantom camera allowed Destin and Dr. Seymour to do, however, is to see the actual timeline of envenomation. A single nematocyst could fire 20 times before you could blink an eye, but the venom itself discharges much later (at least on this timescale). That’s a result which would have remained invisible without a high-speed camera, and proves that even slo-mo videos can be science.
To my knowledge, no one has ever recorded a firing nematocyst like this. It makes Dr. Seymour visibly giddy to see it, and it’s wonderful to hear him say that this kind of learning is what gets him up in the morning. I’d jump out of bed too if I knew I’d get to strap a Phantom camera to an electrified sea anemone tentacle.