You might think you know sharks – but these beautiful, endangered animals are more than meets the eye.
Here are 10 Things You Didn’t Know About Sharks:
10) Contrary to popular opinion, sharks cannot smell a drop of blood a mile away. They do, however, possess a pretty impressive sense of smell due to an enlarged olfactory bulb in their brains. A lemon shark is capable of detecting tuna oil at one part per 25 million, about 10 drops in an average-sized home swimming pool.
9) They also possess electroreception, allowing them to detect weak electric fields in the water. This allows them “see” hiding animals in darkness or obscured by ocean plants.
8) Throughout the Renaissance, sharks had a strange assortment of names: Ziphius, Sea Dog, and De Lamia (named after a child-eating demon in Greek mythology).
7) While other fish use an air-filled swim bladder to stay afloat in water, sharks use their livers. A shark’s liver is filled with oil and can be used to regulate buoyancy!
6) The smallest shark in the world is the Dwarf lanternshark. These guys reach a maximum length of 8 inches – most can be held comfortably in the human hand. As its name implies, the Lanternshark is capable of producing light from a distinctive array of photophores, meaning its body lights up on its own! This feat is called bioluminescence. (Curious about bioluminescence? Check out Light On Earth on CuriosityStream!)
5) Unlike most sharks, the Caribbean reef shark hunts in packs. For this reason, injured Caribbean reef sharks can continue to thrive because their pack-mates will provide them with leftovers.
4) Sharks can go through 30,000 teeth over the course of their lifetime. Unlike humans, sharks will never stop regrowing lost teeth. They grow from the back and move forward as front teeth are lost while hunting.
3) Great White Sharks have evolved such that they must keep swimming in order to breathe. You know the menacing grin of a Great White? That’s not a threat – they simply must keep their mouths open as they move so they can take in oxygen from the water!
2) The earliest shark fossil record is 420 million years old, this makes sharks one of the oldest species still in existence. Sharks were contemporaries of T-Rex!
1) You might be afraid of sharks, but they have much more reason to be afraid of you. In 2017, there were 5 human fatalities due to shark attacks worldwide. That same year, around 100 million sharks were killed due to finning – the process of cutting off shark fins for commercial use.