These Ancient Crocodiles Walked On Two Legs And Had Beaks!
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Modern crocodiles are powerful, heavy reptiles. They spend much of their lives along riverbanks, waiting to ambush prey. But their ancient relatives looked and lived very differently. One example is Sonselasuchus cedrus (S. cedrus). This recently discovered crocodile species lived about 215 million years ago during the Late Triassic Period.
S. cedrus stood just about 25 inches (64 cm) tall. This is about the size of a standard poodle. Though related to crocodiles, the reptile resembled the ostrich-like dinosaurs that roamed Earth about 100 million years later. Instead of teeth, the animal had a sharp, toothless beak for slicing food. Its massive eye sockets suggested strong vision. Its hollow, lightweight bones were built for sprinting across land instead of swimming. Scientists think S. cedrus lived in lush forests, not muddy rivers or swamps.
The most surprising thing about S. cedrus was how it moved as it grew older. Younger individuals likely walked on all fours. But as they matured, their back legs grew longer and stronger. This allowed adults to walk on two legs. This shift has never been seen before in ancient crocodiles.
The study, published in March 2026 in the Journal of Vertebrate Paleontology, was led by Elliot Armour Smith at the University of Washington. It was based on about 950 fossils of the ancient crocodiles found in a bonebed at Arizona's Petrified Forest National Park. They included remains from at least 36 individuals of different ages. This gave the team a rare look at how the animals changed as they grew. The area also contained fossils of ancient fish, amphibians, dinosaurs, and other reptiles. The researchers believe these animals may have gathered around a drying watering hole during a severe drought before they died.
Resources: Livescience.com, Phys.org, Smithsonianmag.com
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30 Comments
ajuni3 monthsI can't believe that a crocodile once could walk on two legs.
fevypusogehe3 monthsGOOD thing they are not around today- reuben_1233 monthsgood thing its extinct but its cool
- reuben_1233 monthswow that is crazy
sojibinafyru3 monthsIf those were alive today we would be cooked guys. Because they would chase us until we are tired and then just turn us in to their dinner.
cats4everrr3 monthsDefinitely not crocidiles👍
fyzodonypuna3 monthsCool
nomonskinwalker3 monthsImagine you're going to Florida and then one of these ancient reptiles ruin your vacation and try to eat you.
datinykid2119 daysno they wouldn't because the Sonselasuchus cedrus would more or so be scared of us given its the size of a poodle, now I'm not saying they couldn't kill people because they could but most creatures wouldn't view you a s prey because animals usually hunt based off of size, that would be like a fly trying to take down a rat.
g-dude3 monthsWow- sojibinafyru3 monthsWhy would they have a beak like birds.
