The rare frilled shark is considered a “living fossil,” as its makeup has remained unchanged for 80 million years. This summer, researchers found one alive and thriving off the coast of Portugal, adding evidence regarding the resilience of this ancient sea creature.
The shark was discovered off the Algarve coast by researchers who were working on a European Union project in the area, the BBC reported. The aim of the project was to "minimize unwanted catches in commercial fishing," but the team unknowingly unearthed one of the rarest and most ancient animals on the planet.
The frilled shark has remained the same, both inside and out, since the time of the dinosaurs, with scientists dating it back to the Cretaceous Period, a time when the Tyrannosaurus Rex and Triceratops still roamed the planet. The creature is incredibly simply and unevolved, most likely due to the lack of nutrients found in its deep-sea dwellings, a previous Japanese study on the shark suggested. The examination revealed that its diet is 61 percent cephalopods—the same class that squids and octopus belong to.
This deep sea dweller is usually found between 390 and 4,200 feet below the surface, which is why it’s rarely seen and wasn’t even discovered before the 19th century (despite being around long before man).
The shark caught this summer measured around five feet in length, but at their longest can be around six-and-a-half feet, IFL Science reported. The Japanese study on these rare sharks showed that they may also have the longest gestation period of any living creature, 42 months.
While its name may sound unfitting for a beast that swims the deep seas, according to Mental Floss, the frilled shark is named after its gills. Pretty much all other sharks have separate gills, but the frilled shark’s first pair of gills stretch all the way across its throat. In total, the shark has six pairs of gills that have “frilly” edges.
The shark also has a unique mouth shape. Its jaw has more than 300 teeth neatly lined in 25 rows, which, according to professor Margarida Castro of the University of the Algarve, are specifically designed to help it “to trap squid, fish and other sharks in sudden lunges,” The Portugal News reported. It’s lined with spines called dermal denticles, which, combined with the teeth, give the mouth an all around frightening look.
All in all, it’s unlikely you will ever come face-to-face with a living frilled shark, but if you do, it’s safe to say: Keep as far away as you can, and whatever you do, try to avoid its ferociously awesome jaw.
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