This fish looks like it’s casting its own “Harry Potter”-style Patronus — but it’s actually an insane optical illusion
Though we’ll never get over the fact that we weren’t born into the Wizarding World, we do have to admit that Earth has its moments, too. And now, thanks to Earth’s mighty cardinal fish — which looks like it’s casting a Patronus whenever it regurgitates — we feel closer to the Harry Potter-verse than ever.
Really, it’s the little things, guys.
BBC Earth filmed one of the little guys in action, with their accompanying @qikipedia Twitter account posting an astonishing gif that quickly went viral.
When the cardinal fish regurgitates, it appears to be casting a Patronus. (Photo by BBC Earth.) pic.twitter.com/mBjInfLCBc
— Quite Interesting (@qikipedia) January 30, 2017
However, as you probably already guessed, that tiny little fish is not actually defending itself using a magical silver animal guardian. Instead, it’s the Patronus-looking puff of light that’s doing its own protecting.
According to BBC, what we’re actually seeing here is an ostracod, which is an ocean-dwelling animal that gives off light when it’s disturbed. It produces chemicals called luciferin and luciferase, which emit light when mixed together, in a process called bioluminescence.
This bioluminescence allows the ostracod to “be seen in the complete darkness of the deep sea,” so when the cardinal fish swallows it in the pitch-black environment you see above, then is disturbed by the light burst and spits it out, it looks like a freaking Patronus.
So while it won’t ward off Dementors, the ostracod still deserves props for being a total self-defending badass. Teach us your ways, tiny ocean friend.