Meet the theropods of the Morrison Formation
Mission Jurassic is officially underway, with top paleontologists from around the world working together within the Jurassic Mile in Wyoming to find and excavate fossils and learn more about life in the Jurassic Period. Here’s a closer look at some of the prehistoric animals the Mission Jurassic team hopes to uncover.
Meet the Theropods of the Morrison Formation
Theropods were carnivorous (meat-eating) dinosaurs. They came in all sizes, from the 2-pound Microraptor to the 6-ton Tyrannosaurus rex. All theropods were bipedal, meaning they walked on two legs, and they had three-toed limbs. Their arms were short, and their fingers were tipped with large claws. They had hollow bones, which made them lighter so moving around took less energy. Believe it or not, even today some distant relatives of theropods still roam the earth—birds!
Take a look at one theropod the Mission Jurassic team might discover:
Allosaurus (“Al-oh-sore-us”) was the most common of the large Jurassic theropods. It could reach up to 30 feet long and weigh more than 2 tons. It had a keen sense of smell that helped it track down prey like Stegosaurus and Diplodocus. Its short arms had three fingers designed to grab prey, tipped with sharp claws up to 7 inches long. Its nearly 80 sharp, serrated teeth curved backwards to keep its prey from escaping. Like all theropods, it lost and replaced its teeth regularly throughout its life –like how some sharks do today. Its long, muscular tail helped it keep its balance while running.
The life of an Allosaurus was filled with danger. Museum specimens across the country have injuries and bite marks that show evidence of violent behavior. Some of these could have been caused by prey like sauropods or Stegosaurus defending themselves, others could have been from other Allosaurus. One specimen, Big Al, had 19 bones affected by either injuries or diseases.