The oceans are massive and so do their creatures. The size varies from the largest blue whale to smallest planktons. Oceans have everything in it to feed its inhabitants. As far as monsters residing in the oceans are considered, we consider blue whale as the largest.
But, this giant is preceded by many monsters like creature that once were residing in the ocean. Some of them are:
Dunkleosteus:
Also called “Armoured death machine”, it was a 33 feet long ultimate predator with a body covered in armor. It loves to feed on large fishes like Sharks and everything it catches. They are believed to occur some 400 million years ago in the oceans.
Megalodon:
A giant whale sized shark that got extinct some 2.6 million years ago is believed to be the biggest shark ever lived. It was 50 feet long and hunts whales. The blue whales of today are believed to have a size equal to just the claspers of Megalodon.
Mosasaurus:
As seen in the movie, Jurassic world, these dinosaur-like fish have a very ferocious nature who swallow its giant prey wholly.
Helicoprion:
It was a spiral mouthed giant fish who got extinct 300 million years ago. It has got the most distinct and craziest teeth arrangement in natural history.
Stethacanthus:
It was a highly skilled hunter with unusual dorsal fin; this bizarre shark feeds on fishes, squids, and crustaceans.
Plesiosaurs:
Lived before 135 million years, this giant was a combination of more than one species. They had a very long neck which was not very flexible.
Jaekelopterus:
These giant arthropods lived nearly 400 million years ago and feed on anything smaller than its own size including members of its own size. These arthropods were believed to be bigger than human beings of this era. They hunt fishes using their rapid shooting claws.
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