Natural plastics are any natural material that has the polymer structure. That is a structure that has a chain of molecules. Natural plastics were used before human-made plastics were invented. Natural plastics are formed with the polymer structure. Examples of these natural plastics are rubber, skin, bones, and even DNA. Rubber from rubber trees were used to make balls thousands of years ago! Before the invention of human-made plastics, humans quickly realized that natural plastics had a great power. This is what natural plastics are!