In the success of Jaws, Spielberg’s genius was about more than the ability to put a gripping story on the screen; it was also about recognizing that the shark in the Jaws novel could make a popular monster. The world has been hooked on the ferocious fish ever since. Not only have people flocked to every installment of that movie, they’ve watched countless shark shows on the Discovery Channel and National Geographic in the decades since.
After all this exposure to shark information, practically everyone knows the basics about them: the largest great whites are about 26 feet long, or more than half the size of the average school bus. At 7,000 pounds, they weigh about half as much, too. While they aren’t the fastest swimmers in the ocean, they are nevertheless impressive — they can go 25 miles an hour in short bursts.
It could be time for a few new facts in areas that haven’t been explored in great detail yet.
Great whites have a sixth sense
Humans and most other creatures have access to dozens of senses, and not just the five that are usually mentioned. Proprioception (a sense for the body’s position at any given moment) and equilibrioception (a sense of physical balance) are just two of them.
When people refer to a sixth sense, they usually don’t refer to any of these; rather, they think extrasensory perception. Sharks have a special sixth sense — electro-reception. They have special sensory organs called the ampullae of Lorenzini that are capable of sensing the weakest electrical signals. They use this sense to zero in on prey and also to navigate using the Earth’s magnetic field.
Sharks never blink first
Mammals protect their eyes with regular eyelids; birds and most fish use an additional set of lids called nictitating membranes. Great whites are different — they have no eyelids at all.
While they do lead an unblinking existence, they do need something to protect their eyes when they fight their struggling prey. At these times, they do something very different — they roll their eyes backwards into their sockets in a kind of reverse blink. It’s an ingenious trick — rather than using separate structures like eyelids, the eyes simply turn inwards.
Great whites spyhop
Television documentary makers love to show how gracefully killer whales and dolphins flip out of the water and fall back in. Somehow, for all the coverage that great whites get, documentary makers don’t make a big deal of their ability to do the same thing. The white sharks stalk their prey deep in the water. When they finally decide to go in for the kill, they race upwards rocket-like, grab their prey, and shoot past, breaching the surface, and then fall back.
Great white sharks also do something called spyhopping–they have the ability to pop their massive heads out of the sea and look around for seals and other prey while holding their breath. While documentary makers don’t seem to make a fuss over this remarkable way in which people can come face to face with a shark above water, eco-tourists visiting Mexico or Africa have long known it. Shark charter tours put a lot into advertising spyhopping experiences.
They are exceedingly modest, and also ferocious
The great white shark is almost never observed mating. Even scientists have a very hard time finding them mating in the wild. Great whites tend to not get together while other creatures are around.
Life for baby great whites starts in a bloodbath. While the great white shark is a fish, it doesn’t lay eggs and wait for them to hatch. Rather, it’s an ovoviviparous animal — it lays eggs, hatches them within its womb, and feeds the embryos with its own unfertilized eggs for months until they are capable of surviving out in the wild.
While inside their mothers, life for little baby shark embryos is terrifying. Each litter starts out with dozens of embryos, but only 2 to 4 shark pups actually emerge. They are the winners of a ferocious and cannibalistic in-utero fight for survival. Over the entire gestation period, they constantly try to eat one another.
When pups emerge from their mothers, they have a full set of teeth and are capable of surviving on their own. Their first challenge appears the moment they are born — their own mothers try to eat them. Pups must run for their lives the moment they are born.
If only you could stroke a shark
Nearly nothing about a great white shark is soft and fuzzy. Shark documentaries give a lot of attention to the kind of teeth these creatures have–up to 300 serrated, razor-sharp teeth in multiple rows.
Great whites actually have more than just these couple of hundred fearsome, sawlike teeth: they are, in fact, all teeth. Unlike other fish, sharks don’t have scales. Instead, they have a layer of denticles–tiny teeth that are hard and sharp. These structures have the exact shape and structure as real teeth, complete with a core pulp cavity, dentine and enamel. Stroking a shark’s skin one way can feel smooth: the other way, it will feel painfully harsh when your hand goes up against the denticles.
Great white sharks can be scared, too
Killer whales don’t usually live in the same areas as great white sharks. When they do, though, they tend to terrify them. Researchers have recorded several confrontations between these two giants of the ocean and have found them to be one-sided. The orca always wins and makes a healthy meal of its prey. The moment a great white shark is killed by an orca, hundreds of other great whites in the vicinity flee. In one case in 2000, researchers had a tagged shark not far from such an orca hunt. The shark quickly dove deep into the ocean and began to make its way to Hawaii thousands of miles away.
Finally, if you can’t understand why you never see a great white shark in an aquarium, there’s a reason — they don’t survive well in captivity. No aquarium has ever managed to keep a great white shark alive for more than a few days. They refuse to eat in captivity and can’t seem to figure out walls. They constantly bump into them and injure themselves.