You Won’t Believe These Mind Boggling Animals Once Existed



This prehistoric bird is also known as a “Terror Bird,” and for a good reason. These carnivorous birds existed during the Cenozoic period, about 65 million years ago. Weighing half a ton and standing 10 feet tall, Phorusrhacid is the largest flightless bird of all time.

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Koala Lemur

Technically known as the Megaladapis, the Koala Lemur existed during the late Pliocene period before eventually becoming extinct during the Holocene period. Although there seems to be no relation between the lepi-lemur and the Koala Lemur, this hasn’t stopped scientists from speculating for years about the creature. The main difference between the two is that the Megaladapis has a much bigger skull size, similar to that of a gorilla. They are believed to have once inhabited the island of Madagascar.

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Translating into “Sharov’s Wing,” this unique extinct creature had a delta-winged glide, making it a skilled long-distance glider. What made the Sharovipteryx so special was that it had wings attached to its hind legs, as opposed to most winged creatures that have wings attached to their front legs. It must be stressed though, the one-foot-long Kazakhstani creature couldn’t fly – it could only glide. The lizard-like reptile was commonly known as Podopteryx, or “foot wing” before becoming the Sharovipteryx in 1981.

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Many dinosaurs were large and ferocious. However, this creature was small and lush in appearance, in comparison. It is believed that the Epidexipteryx was one of the first creatures to possess ornamental feathers, similar to that of a peacock. Living during the Upper Jurassic age in parts of Mongolia, this feathered reptile was tiny compared to the average human being, with a skeleton measuring 10 inches if you exclude its feathers. And it was believed to weigh 164 grams, one of the smallest paravian dinosaurs to ever exist.

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One of the most distinctive features of the Helicoprion was its strange spiral arrangement of teeth, referred to by scientists as tooth whorls. The first discovered tooth whorl was found in 2011 in Idaho. They are believed to be one of the longest living prehistoric creatures, living for over 60 million years before their extinction. These shark-like holocephalids are thought to have been over 13 feet long. This is much longer than their living relatives, chimaeras, which are only 5 feet at peak length.

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Don’t let the friendly name fool you, the Andrewsarchus was a ferocious creature. A carnivorous mammal of gigantic proportions, this beast is believed to have been one of if not the largest mammal predator to live on land. After unearthing its skull and many of its bones, paleontologists believe that the Andrewsarchus could have weighed up to 4,000 pounds. And despite being related to hippos and whales, this fierce creature was larger and more destructive than even the Tyrannosaurs Rex.

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Woolly Rhinoceros

We are used to recognizing rhinos as hairless mammals that have clear, visible links to the prehistoric era. However, there was once a rhinoceros that possessed a full coat of wool. After 3.6 million-year-old fossils were unearthed from a variety of locations, they were originally believed to be from the claws of a prehistoric bird. Also, there have been mummified specimens found in Siberia, indicating that the average woolly rhino weighed between 4,000 and 6,000 pounds and were between 9.8 to 12.5 ft in length.

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The Gigantopithecus lived between 9 million and 100,000 years ago and is believed to have been the largest ape to have ever existed. The humungous creature could weigh up to 1,200 pounds and the tallest grew to a staggering 10 feet. One of the biggest debates surrounding the Giganthopiethecus was whether it walked on all fours like most other apes or walked on two feet more like a human. Also, it had such strong teeth that it could chew the toughest of foods.

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The Rodhocetus is a fascinating example of a creature that evolved from living on the land to living in the sea. The Cetacea infraorder, which consists of animals such as whales, dolphins, and porpoises, also included the Rodhocetus. His webbed feet and hands are a clear indication of a seafaring creature. Because it had a mix of characteristics associated with both land and sea mammals, researchers believe that the peculiar beast was a natural bridge between land and sea animals.

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The Megalania existed up until about 30,000 years ago. As it was located in Southern Australia, there’s a good chance that early aborigines may have shared the land with these ferocious reptiles at the same time. Although there is much debate as to what the exact size of the lizard was, many believe that the largest Megalanias could have been at least 25 feet long. This means that it would have been the largest land living lizard to have ever existed.

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Also known as the “chambered horn,” the Cameroceras existed during the Ordovician period and inhabited many seas. It is an ancestor of the squids and the octopuses of today, which is clear from this re-imaginative design. This mollusk was identified for its distinctive features, which included a shell shaped like a shell as well as tentacles that it used to hunt smaller sea creatures. It is believed that the Cameroceras’ shell could have been anywhere between 20 and 40 feet long.

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Meganeura is regarded as one of the largest flying insects to have ever existed. This is mainly due to their large wingspans that ranged between 25.6 inches and 27.6 inches. Although the connection is not clear, researchers believe that they are related to and heavily resembled modern-day dragonflies. Having existed during the Carboniferous period, the insect was believed to have been a notorious predator, preying on small insects and even having a hunger for amphibians. Megeneura translates into “large-nerved,” alluding to the many veins in their wings.

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One of the ancestors of modern-day crocodiles and alligators existed nearly 80 million years ago. As you can see in the image, the Tyrannosaurus Rex would have been no match for this amphibious beast. Despite the fact that it strongly resembled crocs of today, they were much bigger. The Deinosuchus was 40 feet long and possessed an impressive set of large, sharp teeth. It had the ability to crush turtles’ shells with its teeth and regularly ate fish and even the largest of dinosaurs.

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Translated into “abnormal shrimp,” this is the perfect way to describe the Anomalocaris, one of the Cambrian sea dwellers. This marine creature was very similar to arthropods that came before it. Researchers believe that the Anomalocaris was a predator whose diet consisted of sea creatures that possessed the toughest of shells – most notably, trilobites. One of their most distinctive features was its eyes. They are believed to have contained over 30,000 lenses, giving it one of the clearest visions of its time.

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This large carnivorous fish existed about 380 million years ago during the Late Devonian Period. The Dunkleosteus was a humungous fish, believed to be over 33 feet long and weighing up to 4 tons. In its heyday, it was the most feared predator of the sea. What made the fish so heavy was its tough protective layers, acting as an armor from other predators. And although this made the Dunkleosteus fairly slow, its swimming skills were still up there with the very best.

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Giant Australian Python

The Wonambi Naracoortensis, better known as the Giant Australian Python, existed during the Pliocene period. It’s technical name, Wonambi comes from the Aborigine language and translates into “rainbow serpent.” Despite not having the same level of flexibility as modern snakes, this python was huge and force to be reckoned with. What is clear is that the Wonambi was alive at a time when lizards were slowly evolving into the snakes of today. This is because lizards have no flexibility in their jaws.

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Although the Tyrannosaurus Rex is considered the most feared dinosaur of all time, the Spinosaurus was even bigger. At 18 meters in length and 10 tons in weight, it was the largest carnivorous dinosaur that ever existed. What added to the horror of this creature was its tendency to eat sea dwellers like fish and turtles, as well as other dinosaurs. The reality is that if the Spinosaurus was still around today, the existence of humanity would be put into serious question.

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The Smilodon is officially the best known saber-toothed cat and one of the most famous prehistoric mammals in the paleontology.  This machairodont felid was native to the Americas about 10,000 years ago during the Pleistocene period. Also known as the saber-tooth tiger, what made the Smilodon so ferocious was its strong physique. It possessed abnormally long and sharp front teeth, designed for precision killing. Its diet usually consisted of herbivores such as bison and camels and they usually weighed about 900 pounds.

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Eurypterids were essentially a combination of alligators and scorpion. Although they are referred to as the scorpions of the sea, they are not scorpions in the true definition of the word. It was an arthropod related to arachnids but were often the size of alligators. These ocean dwellers were global and existed up until about 252 million years ago.  Although most were about 8 inches long, some subspecies such as the Jaekelopterus were much bigger. The word eurypterid literally translates into “wide wing.”

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Great Auk

Often regarded as the original penguin, the great auk was often about 3ft tall, and had very small wings. They were residents of the North Atlantic waters for hundreds of years and made homes in many countries such as Norway, Canada, and France. Despite their resemblance, the great auks were not actually related to what are now known as penguins. They were simply referred to as Pinguinus impennis because of their physical similarities to the more famous flightless birds.

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One of the most unique looking creatures on this list is without a doubt, the Opabinia. What makes this prehistoric sea dweller so odd-looking is its five eyes for seabed navigation and its long, hose-like nose. It would use this to bring food to its mouth, similar to that of an elephant. Also, its 30 flippers on either side of its body add to the peculiarity of this one of a kind. It’s hard to believe that this actually existed at one point.

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You may be thinking: why would a creature be called a Hallucigenia? Surely it can’t put a spell on its prey. No, this is not the case. However, the reason this work-like creature has such a name is due to its bizarre and patterned-spikes that make it somewhat hypnotic to look at. Although the creature had no eyes or nose to sense its surroundings, its tentacles on its back are what helped it navigate. There is no denying the enigmatic quality of the Hallucigenia.

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This creature that shared many physical similarities with the modern day armadillo was actually more closely related to a completely different species of today. It is believed that the Glyptodon was an ancestor of modern-day turtles, mainly due to its shell that it carried on its back. Like turtles, the Glyptodon was a herbivore. And although it couldn’t retract its head like its descendants, it did have a boney head covering in order to protect itself from carnivorous predators.

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Literally translating into “bear dog,” the Arctocyon existed during the early to late Paleocene period. Although its descendants, the capybara, is not considered a dangerous creature, the Arctocyon was ferocious in comparison. This ground dwelling omnivorous beast could walk on its hind legs like a bear and was a fast runner like a dog. This lethal combination made it a force to be reckoned with in the animal kingdom of its time and with its razor sharp teeth, was able to tear its prey apart limb from limb.

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As you can see, it is quite clear that the Platybelodon was related to what we now know as the elephant. Also known as the flat-spear tusk, or the shovel tusker, this herbivorous mammal shares virtually every single similarity with elephants except for one thing: a trunk. The Platybelodon simply didn’t have one and instead had a long protruding mouth and nose, similar to that of a duck. Researchers theorize that they used it to hold onto the tree branches.

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It is pretty clear what species the Carbonemys paved the way for. This giant turtle existed over 60 million years ago. This means that it actually survived the mass dinosaur extinction. Unlike modern-day turtles, that have a complex diet depending on their environment, the Carbonemys love to eat reptiles and had jaws that were strong enough to eat crocodiles. With a shell that was almost 6 feet long, it is widely considered one of the largest turtles to have ever lived.

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Also known as the “Thin Plate Lizard,” the Elasmosaurus had an extremely long, flexible neck. Having existed during the Late Cretaceous period, this lizard was originally believed to have had a long tail and short neck. The reality was that it was actually quite the opposite. Believed to have measured approximately, 46 feet, or four Mini Coopers, the Elasmosaurus was a fierce master of the sea. It was impossible, though, for the creature to raise anything more than its head above water.

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This ancestor of today’s sharks became extinct about 323 million years ago. The Stethacanthus had a peculiar appearance, sporting an upper dorsal fin. In fact, the name Stethacanthus literally means “spine chest,” referring to the anvil-shape on its back. It would have been used to for a variety of purposes. These included attacking prey, scaring away predators and even for mating. There is no denying the similarities between this shark and the design of the Starship Enterprise, but we think that’s a mere coincidence.

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The essence of this snake is clearly in the name. The Titanoboa was a titan of the serpentine world. Living for over 10 million years, this snake is widely considered to be the longest, largest and heaviest snake to have ever existed. It lived about 60 million years ago during the Paleocene period. Estimations show that the Titanoboa probably weighed about 2,500 pounds and was at the most, about 42 feet long. It was able to eat large turtles and even large crocodiles.

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Although it may look like a cross between a zebra and a horse, the Equus quagga quagga was simply just a version of zebra that ceased to exist in the 19th century. Ultimately, it was the sound that the animal made that earned it the name Quagga. Sadly, the South African equine creature was hunted so much that it was unable to maintain its existence, with the last Quagga dying in 1883. They were killed off for the benefit of the other farm animals.

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Pinta Island Tortoise

Native to the Galapagos Island, the Pinta Island Tortoise was a giant in the tortoise community. However, it reached its untimely demise in the 19th century, after being hunted down for food. What sealed the nail in the coffin was when goats were brought to the islands and ravaged the tortoise’s natural habit. In the end, there was just one who remained – the legendary Lonesome George. Scientists desperately tried to breed George with other tortoises, but to no avail.

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Tasmanian Tiger

Technically known as the Thylacine, the Tasmanian Tiger wasn’t actually a tiger. In fact, it was a marsupial, which should come as no surprise, seeing that it hailed from Tasmania. Most importantly, it was the largest carnivorous marsupial of all time. Ultimately though, the Thylacine was hunted down because humans considered them a threat to their livestock. Other impressive features of the Tasmanian Tiger included its jaws, which could open up to 120 degrees! Also, both sexes had a pouch.

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Steller’s Sea Cow

It was Georg Wilhelm Steller who first discovered the Hydrodamalis gigas. As a result, the large, herbivorous sea mammal became better known as Steller’s Sea Cow. As it was an extremely tame creature, and its preference to dwell in shallow waters, the Sea Cow was subject to mass to hunting until it eventually became extinct just three decades after it was discovered. The hunters ended up following Steller’s route and used the Sea Cow for food and boat linings.

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Originally from New Zealand, the flightless Moa was a tall, imposing bird who could grow to a staggering four meters in height! However, when the Maori people first arrived on the island in 1300 A.D., this sparked serious danger for the bird. In less than a hundred years, the Maoris wiped out all of the Moas. That wasn’t all though; they also caused the extinction of the Haast’s eagle, which was the original threat to the Moa’s existence before the Maoris’ arrival.

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Japanese Wolf

Also known as the Honshu Wolf, seeing that it hailed from the Japanese island of Honshu, the Canis lupus hodophilax could also be found on the neighboring island of Hyushu and Shikoku during its existence. At just three feet long, the Honshu wolf was officially the smallest wolf in the history of cani lupi. What ultimately led to its downfall was the growing rate of rabies in the 1700s. Seeing that it made them much more aggressive, the wolves were eventually killed off by 1905.

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There is no denying that the Quetzalcoatlus was the largest creature to ever fly. This 40 feet tall pterosaur was a god of sky and had such a unique physical makeup compared to any other flying creature in existence. One of its most distinctive features is its long, thin neck. It existed during the Late Cretaceous period in North America and is a member of the Azharchidae family. And although it is debatable how the Quetzalcoatlus took to the sky, the general consensus is that it did fly, despite its large size.

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