Chapter 4: Teeth Everywhere

This chapter was really unique because Shubin talked about how teeth becoming one of the main fossils to excavate. 'Out of all the bones and organs, why teeth,' I asked myself. Well, as Shubin went on, he said that teeth is the easiest fossil to preserve because of the material that it's made up of, which is hydroxyapatite. Moreover, it is interesting to say that many organisms from fish to humans have this material in their body. Shubin's discovery of the various fish from the million years ago had this structure in their body to chew up other fish; even the small fish could chew up the big fish through this hard structure. However, what was more peculiar was that these fish used the hydroxyapatite to even armor themselves, as seen through the ostracoderms. Shubin's description of these species as hamburgers with fleshy tail, was pretty funny, seeing the picture right below. Also, the diagram on page 79 really amazed me. Many of the organs came from the layers of skin, transforming into the organs that we require. Through this diagram, I now realize that the discovery of teeth fossils really changed the views of paleontologists.