Most paleontologists look into the mouth of an allosaurus and see a prehistoric eating machine with a jaw full of flesh-tearing teeth. Peter DeRosa peers into that mouth and sees the hand of God. Working from a business park about 80 miles north of Tampa, Fla., DeRosa and his family are hammering away at two bedrock principles of modern science: evolution and the notion that Earth is about 4 billion years old. The DeRosas are part of a small but growing band of creationists using dinosaurs - the icons of an ancient Earth - to argue that the world is...