Ladies, gents and juice boxes, I introduce to you the scariest shark of the deep: the cookie cutter shark (Isistius brasiliensis).
Want to make these sharks even cooler? They take on animals many times their size. Anything from edible fish (i.e. sharks) and mammals (i.e. whales and dolphins) to non-edible submarines (i.e. the rubber part of the sonar dome has gotten so badly bit it caused an oil leak and the submarine had to surface).
Now, no worries, mates. These sharks aren't out to take chunks of meat out of your legs as you swim. There have been a few encounters between humans and this small shark and they are positively bizarre. (I mean, come on.)
One question we have left unanswered: "How does it do it?" Well, as you can see from the pictures, they have very sharp teeth. They sort of remind me of a bear trap, to be honest.
See? Same thing, practically.
But, before I delve into that little nugget of information, let me say that these bites are usually not fatal to large animals, just leaving them a gnarly scar to tell their friends about. Those smaller animals like squid, though? Can we say, "oops..."
Lets have a moment of silence for all the poor squid who were the cookie shaped chunk. (What, your gingerbread cookies aren't squid? You're doing it wrong.) And once you're done weeping over squid, continue to read about their glowing features.
Like many deep-sea critters, these sharks have bioluminescence to to help with camouflage. This bioluminescence pattern is actually broken up, so it looks either like small, tasty treats (which lures big fish to the shark and then chomp!) or light filtering down from above and uninteresting to predators (they are known to swim in schools to achieve this). Win-win situation in my books.
Another neat fact: Like other sharks, they shed their teeth... but unlike other sharks, they don't replace single teeth but entire rows at one time. I'm imagining dentures for a cookie cutter shark and the picture in my head is way more amusing than it should be.
Sadly, not a lot is known about the cookie cutter shark- including its reproductive life history! Someone should look into that... any deep sea shark biologists want to take me along? I've got a calendar wide open.
As such, the International Union for Conservation of Nature (IUCN) has listed the cookie cutter shark under Least Concern, seeing as this sucker is everywhere, has no commercial value and isn't really fished.