Specimen:  MOEH 601

Excavated:  China, 1990s

Length at birth:  est. 10 to 12 in

Weight at birth:  est. 2 lbs

The Edmontosaurus was a type of hadrosaur, or duck-billed dinosaur, which could grow to be 32 feet in length and weigh between 3 to 4 tons. There have been a number of fossilized dinosaur eggs found, and surprisingly they are extremely small (for the size of the animal).  The largest egg belongs to a Sauropod called Hypselosaurus, which could grow to 40 feet in length, but its egg was a ball-shaped structure only 10 inches in diameter.  Dr. Jack Horner of Montana State University made a discovery of several eggs of a hadrosaur called Maiasaura (means "Mother Lizard"), in which the tiny skeleton of the unborn dinosaur had fossilized. The Maiasaura could grow to be 30 feet in length, but the babies were only 11 to 12 inches long at birth. The Brachiosaurus, which could grow to be 75 feet long, 40 feet high, and weigh 75 tons, had an egg that was the size of a football.