Cows of the Cretaceous
Edmontosaurus and other duck-billed hadrosaurs lived on plants—lots of them. Sturdy front legs with hooves helped them move on all fours as they cropped low-growing vegetation with their horny beaks. Fossil footprints show they also walked on hind legs to snap off higher leaves and branches.
Edmontosaurus, one of the last and largest ornithopods, weighed up to 13,000 lbs. (6,000 kg)—the result of an evolutionary trend toward bigger bodies.