Pachycephalosaurus (pronounced PACK-ee-CEF-ah-loh-SORE-us) was both the biggest member of the bone head family of dinosaurs and the last member to exist. Its length was about 20 feet and weighed 1to 2 tons. It was a herbivore (plant-eating) dinosaur.
Carnegie Museum of Natural History at 4400 Forbes Avenue in Pittsburgh has a Pachycephalosaurus on display in its exhibit, "Dinosaurs in Their Time". Also paleontologist at the Carnegie Museum developed a model replica of the Pachycephalosaurus dinosaur from fossilized skeletal remains.
Interesting feature of the Pachycephalosaurus is its enormous dome on the top of his head. It was made of solid bone some 10 inches thick. Like a great crash helmet, its thick skull could have absorbed a tremendous impact as rival males butted each other head on.
Pachycephalosaurus truly used its head (skull) to compete for supremacy of the flock by banging their bony crowns. In the movie, Jurassic Park : The Lost World, there is a small Pachycephalosaurus ramming a vehicle with its head.
Dinosaur fossils of Pachycephalosaurus have been found in Alberta, Canada and Wyoming, USA. Pachycephalosaurus scientific name means "thick-headed lizard".
For more information on Pachycephalosaurus go to http://www.carnegiemnh.com.