These Theropod dinosaurs were believed by Darwinian adherents to live during the late Cretaceous era 70 million years ago in both North America and Asia. It's name means "Thick headed lizard". The first fossil evidence of them was uncovered in the form of skull fragments by Donald Baird in 1859 in southeastern Montana, but was not described until 1872 by Joseph Leidy who proclaimed the bone belonged to a large armadillo-like animal or possibly reptile of some form.
The anatomy of Pachycephalosaurus is still poorly known, but comparative anatomy has helped paint a fuller picture of it by using other members of it's family to model off of. Pachycephalosaurus is generally believed to have been about 15 feet long and their skull cap was comprised of bone 10 inches thick, making it the largest member of the Family Pachycephalosauridae. The skulls of these animals have produced significant troubles for researchers since different age/growth stages are now known to have had differing skull anatomy which led to many "species" being coined only to now be recalled and correctly classified as a single species that goes through drastic reconstruction as it matures. This is of particular interest to Creationists who point out the amazing diversity in the created Kinds.
It has been believed for a long time now that "Pachy's" used their thick bony skulls to ram one another much like Musk Oxen or Big Horn Sheep, however some scientists have recently stated that this may have been impossible. Many now believe that these creatures did not butt heads like Musk Oxen, but rammed their opponents in the side. This is based on a lack of scarring on the skull domes, the thick, broad torso of the species that would be fit to protect internal organs, and the fact that their necks were "S" or "U" shaped instead of straight which would make them unsuited for head-to-head combat ramming. This has sent dissent into the theory and creating two groups defending both claims. This may help provide the true answer to the issue or it may severely hinder it, only time will tell. Although it has also been suggested that the creatures rammed one another's broad flanks which seemed to be designed to protect their organs from just such activity.
Scientists are unsure what Pacycephalosaurus' ate, but it is currently believed that they were omnivorous, eating plants and insects. Their muzzle (snout) is small and ends in a pointed beak that would likely have been suited for browsing. Their teeth were sharp and serrated which would have been well adapted for soft plant matter as well as the possible occasional animal protein. With such adaptations it may well be that Pachycephalosaurus was an omnivore that primarily fed on soft vegetation such as fruit and vegetables and the occasional insects or maybe even small vertebrates, though this cannot be proven without a live specimen.
Such amazing animals show all the signs of having intelligently designed in order to have such amazing features suited for their survival. Such uniqueness can be said of many animals, yet this fine tuning cannot be adequately exlained by gradual, undirected Evolution, leaving only one possibility.