It's #fossilfriday! Meet Stegosaurus! "Stegosaurus means "roofed lizard," which was derived from the belief by 19th-century paleontologists that the plates lay flat along its back like shingles on a roof. But most evidence supports the idea that the plates alternated in two rows, pointy side up from the dinosaur's neck down to its rear. Its 17 plates, called scutes, were made of a bony material called osteoderms but were not solid; they had lattice-like structures and blood vessels throughout."