Knowing what is and isn’t dangerous when you’re in unfamiliar territory is tricky, but there are a few signs you can look out for, such as teeth, bright coloration, or the resemblance to a bear on a lot of cocaine. A video that recently went viral on TikTok demonstrated how easy it is to underestimate small things, as someone was filmed holding in their bare hands one of the most dangerous animals on the planet (amazingly, it's not even the first time this has happened).
The blue-ringed octopus is the definition of small but mighty, with an average body size of just 12 to 20 centimeters (5 to 8 inches). As its name suggests, these small squishies are covered in a psychedelic pattern of blue rings – but these are only normally visible when the animal is provoked. When stressed, it turns bright yellow and flashes its 50 to 60 blue rings in what’s normally received as a pretty clear “back tf up” signal.
It’s a fine example of an aposematic warning display, a technique used by a diverse range of animals that lets would-be predators know that this is not a snack they want to take on. The perceived threat could pertain to venom (injected), poison (ingested), foul taste, or hard-to-swallow spines. Another defense that is a little sneakier is seen In Batesian mimicry, in which a perfectly edible prey species mimics an aposematic model so that predators avoid them too (such as this "tarantula").
In the case of the blue-ringed octopus, they’re not messing around. They really are one of the most dangerous animals on the planet, owing to the extremely harmful toxin they can envenomate attackers or curious hands with. It’s called tetrodotoxin and it is a powerful neurotoxin that can be fatal. Fortunately, these octopuses aren’t aggressive, so if you give them space and don’t, say, take it out of the water and pass it around, you should be fine. Otherwise...
“Its bite is usually painless, so you might not know you’ve been bitten until it’s too late,” wrote marine ecologist Erin Spencer on a post about blue-ringed octopus for Ocean Conservancy. “First, the venom blocks nerve signals throughout the body, causing muscle numbness. Other symptoms include nausea, vision loss or blindness, loss of senses and loss of motor skills. Ultimately, it will cause muscle paralysis – including the muscles needed for humans to breathe, leading to respiratory arrest. There is no known antidote, but victims can be saved if artificial respiration is started immediately.”
It seems, then, that @kaylinmarie21 (whose TikTok bio now reads “I held a venomous octopus once”) was unbelievably lucky. In a follow-up video to the original detailing her nail-biting wildlife encounter, she explains that she was visiting the Uluwatu beach in Bali with some friends when they spotted not one but two blue-ringed octopuses. Though her original video only shows the one being handed around, she explains that they also picked up the second. In the video, the octopuses’ rings can be seen very clearly demonstrating how the venomous ticking time bomb was feeling at the time of the photo op.
The story, told so far in just two of three parts, seems to have a happy ending. At the time of writing the original video sits at 8.7 million views, and while this incident was sort of an accident we’d strongly recommend keeping wildlife out of your TikTok content where possible. Even walking toupees can kill you.
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