In the early 17th Century, Nicholas Steno changed the world of discovery when he noticed the similarities between shark teeth and rocks known as "tongue stone". He made the way for more discoveries and opened up the way of fossils everywhere. Not to far behind him, Mary Ann Mantell picked up a tooth thinking it was from a large iguana. It turned out to be a tooth of a dinosaur named Iguanodon. This shocked the world and made them realize that many fossils are from species that are no longer with us. Without those two's discoveries we wouldn't know the things we know or have the things we have. We wouldn't have all the museums just for dinosaurs, if we didn't have dinosaurs! Although we may take the fossils for granted, we still learn so much