Here's What You Should Know About Mastodon Fossils Paleontologists and researchers explore different ways to enhance their knowledge in their areas of interest. Take fossils for instance. Even though there are a myriad of fossils of animals and marine animals, researchers get certain fossils for their study. While some of them may get a Mastodon tooth on sale, there would be others who would get fossils of marine animals and other predators in the past.