Livyatan’s teeth are some of the most awe-inspiring fossils in the world. It’s not clear whether or not Livyatan hunted alone or in packs, like a modern killer whale, but it had the power and size to be able to plausibly compete with Megalodon even solo. Here we shall find the NIGHTMARE SHRIMP. Long-held to be a trilobite-hunter, recent studies have shown it would probably have had to restrict itself to soft-bodied prey due to relatively flimsy mouthparts, and therefore could only have actually eaten a trilobite just after a moult. 10. Thanks to a fluke of geology, the conditions that produced the Burgess Shale were also capable of preserving soft tissue, giving palaeontologists a rare chance to look into what the seas looked like during the first days of the animal kingdom. 10. Fast-forward even further, to the early Jurassic (175 million years ago), and you have Temnodontosaurus eurycephalus. Let’s take a lobster. Now that you have a saltwater crocodile in your head, make one, oh, twice as big. The fauna found in the Burgess Shale was almost obnoxiously uncategorisable. Disclaimer: an old friend of mine is a paleontologist who specializes in the Burgess Shale fossils. Armored skin thick enough to turn aside more or less anything. Its legs were replaced with bladed paddles for maneuverability and it had a powerful tail for direct propulsion. Dunkleosteus was also 33 feet long from tooth to tail and covered in thick armor-like plating, making it one of the ocean’s first giant predators. Known to be 20 feet long, it didn’t really have teeth so much as a huge bony beak, which honestly makes the whole contraption even more frightening, like some sort of mobile oceanic guillotine. It was also delightfully strange-looking. This article was originally published on SB Nation a while ago, but was always intended for a Secret Base-y audience. Salties are strong, fast and surprisingly smart. Modern sperm whales are enormous creatures, but very rare boat attacks aside, they’re only really dangerous to their favorite prey, deep-swimming squid. Aren’t you glad they’re dead? They looked extremely weird. (A personal favorite of mine is Lunapsis, which looks like a fish had a baby with Batman’s utility belt.) Let’s make the required tweaks. With good eyes set on flexible stalks and a surprising turn of speed, Anomalocaris canadensis cruised the Pre-Cambrian seas in death-shrimp mode. Nature, of course, does not ‘come up with’ anything. Yeah, like that. Sea scorpions the size of crocodiles swam in the same waters as massive armored fish who could bite a great white in half. But nevertheless, the box jellyfish, also known as the sea wasp, is more responsible for human deaths on the continent of Australia than snakes, sharks, and saltwater crocodiles put together.Source: National Geographic Its flippers were nearly 7 feet (2m) long, allowing it to swim the depths with deadly efficiency. Here are 9 of the most badass animals ever to swim. Leviathan. This ancient fish lived 400 million years ago, but its bite has stood the test of time. Say hello to some horrifying sea monsters. Apparently, these things liked to swim up from underneath its prey and bite through their chest to reach their internal organs. Shastasaurus. Unlike most crocodiles they’re capable of jumping clear out of the water to get to it. Let’s make them better swimmers, too — we’ll add some paddles for agility and short bursts of speed. Well, a lot carried away. These are some of the deadliest creatures of all time, the ones who epitomize the phrase “there’s always a bigger fish.”. Flower urchin (Toxopneustes pileolus) | Photo: Philippe Bourjon / License. Whales are the largest living creatures in the sea, but these gentle giants were preceded by some of the scariest sea monsters of all time. That’d be a bad day. They were absolute apex predators, preying on sharks and basically anything it could catch (everything). Megalodon died out only relatively recently. at nighttime or dug it out of the mud, but since paleoecology is at least in part about imagination, right now I’m enjoying Cameroceras retracting its head deep into its shell and pretending to be a cave before trying to eat whatever entered. But it’s much more fun to imagine this guy roaming the seafloor chomping down on everything, so that’s what we’ll do. Decently boat-sized. One closely-related species possessed the largest eyes of any known animal, perfect for hunting in deeper oceanic waters; another has been found with the remains of a different ichthyosaur in is stomach. 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