Spoiler: they're not sucking in air for Christ's sake!
Pufferfishes inflate themselves when they sense danger. They do it to defend themselves for the inflation makes them more difficult to eat--they can grow as much as twice their size, not to mention their sharp spines.
While this has known by almost every adult being, a particular video of their deflation has gone viral and it's not just because of how cool it is to watch. People appeared to have the misconception that pufferfish somehow inflate by filling themselves up with air!
Well, yes, they look like a balloon but this doesn't mean they work the same way! Thanks for this Twitter video, though, for the chance to clarify this once and for all: pufferfish, when in panic mode, don't inflate with air.
Instead, they do this by rapidly gulping water into their stomachs. This, then, stretches their extremely elastic skin, consequently making their spikes stand. They can stay like this for a long time and deflates when the predator finally gives up on eating them. Moreover, when out of water, they can fill themselves with air but this can quickly suffocate them.
But don't worry, even scientists had their own misconception with this strange creature before. For a long while, they believed pufferfish were "holding their breath" when they did this (just like in Finding Nemo). That is because they thought this hinders their gills.
Researchers at James Cook University and the Australian Institute of Marine Science got that cleared up, however, when they found that pufferfish still actually take in oxygen as they inflate.
Now you know what's up with this toxic inflatable fish, you can go pass this education to everyone!
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