strangest prehistoric creatures to rule the earth

Translated from Greek to mean crowned crocodile, Estemmenosuchus is quite a strange looking prehistoric creature. Though it looked like a hipporhino mix, this creature had distinctive knoblike horns on the sides of its head (and, in some species, on the top and on the jawbone). Thankfully, it was primarily a herbivore.

Capybaras arent feared animals today, but this prehistoric animal was far from cute and cuddly. Nicknamed the bear dog, Arctocyon could walk around on its hind legs and tear apart whatever it sunk into with its razor sharp teeth.

Though it looked like a squished (though terrifying) sardine, Dunkleosteus holds the record for the strongest bite of any animal, living or extinct. Able to fit a human in its mouth with one chomp, this bizarre prehistoric creature ruled the seas for 20 million years, leaving destruction in its wake. A pure carnivore, Dunkleosteus could weigh as much as an elephant and reach up to 33 feet (10 m) in length.

Flightless birds with similar characteristics to the ostrich, Phorusrhacids could reach land speeds comparable to cheetahs. Up to 1,000 pounds (454 kg) and 9 feet (3 m) tall, these creatures could easily grasp a mediumsized dog in a single bite (and their hooked bill allowed them to tear into larger animals as well.) They really deserve their nickname, the terror bird.

If youve ever experienced whiplash, you can imagine how tough a life this plesiosaur had. With a body which was mostly neck, Elasmosaurus was originally put together by paleontologists the wrong way: with a short neck and elongated tail. (It was also originally depicted as having a flexible, snakelike neck which has since been refuted.) Measuring about 46 feet (14 m), Elasmosaurus prowled the oceans at a length of nearly four Mini Coopers endtoend.

Dunkleosteus may have been big, but Helicoprion holds this lists top spot for most bizarre, seadwelling prehistoric creature. Helicoprion was an ancient sharklike fish with a modified jaw: its lower palate was a circular saw of teeth which could tear flesh from bone, grinding the flesh against its top teeth.

Related to the Helicoprion, Edestus Giganteus was as terrifying as it was strange. Commonly referred to as the scissortooth shark, Edestus Giganteus had an interesting set of chompers. Rather than replace its teeth as they wore out, it would grow new teeth and gums at the back of its mouth, pushing older teeth and gums out of its mouth. The older teeth would eventually protrude and hang out of its mouth.

Diprotodon Optatum is the largest known marsupial (mammal with a pouch) to have ever existed. About the size of a hippopotamus and comparable to a wombat with saggier skin, Diprotodon Optatum lived in Australia during the Pleistocene period and may have run across our relativelynear indigenous ancestors.

Linhenykus doesnt look that different from our general conception of dinosaurs bar one big (well, little actually) feature: its finger. Linhenykus had only one tiny finger on each of its arms, the only nonavian dino to have but one. Scientists still arent sure the purpose, especially given its large feet.

Longisquama is a lizardlike creature with what appears to be hockey sticks longer than its whole body jutting out of its back. Paleontologists know little about this reptile found in Central Asia and a longstanding debate continues on whether Longisquama was a prehistoric bird or something else entirely.