Ankylosaurus was an armored dinosaur that lived roughly 67 million years ago, at the very end of the Cretaceous Period. This genus was among the last of the non-avian dinosaurs, living alongside Tyrannosaurus, Triceratops, and Edmontosaurus. Its name means "fused lizard"; bones in its skull and other parts of its body were fused, increasing their strength. Ankylosaurus was up to 6.25 m (20.5 feet) long and 1.7 m (5.6 feet) tall, weighing about 4.8–8 tonnes (11,000–18,000 lb). It had a broad, robust body with a wide, low skull. The front parts of the jaws were covered in a beak, with rows of small, leaf-shaped teeth behind it, adapted for a herbivorous diet. It was covered in armor plates for protection against predators, with bony half-rings covering the neck, and had a large club on the end of its tail which may have been used as a weapon. Fossils from a few specimens of Ankylosaurus have been found in various geological formations in western North America, but a complete skeleton has not been discovered. (Full article...)