Chapter 4: Teeth Everywhere

I found this chapter surprisingly interesting; I never would have thought that teeth were so significant in discovering our connection to the rest of life.

I enjoyed reading about Shubin's early expeditions because they showed how he matured into a distinguished paleontologist and became more comfortable in his career. At first, he was clueless in finding fossils and needed the guidance of a fellow colleague, Chuck. But soon, Shubin mastered this skill and led an expedition of his own to Nova Scotia. Furthermore, Shubin's dedication and patience are once again evident through his expeditions.

I was amazed when I read that ostracoderms have a shield over their head that are entirely composed of little tooth-like structures. The original purpose of teeth was to bite food, but in this creature, teeth are fused together and are used for protection. I also found it interesting that creatures have hair, scales, feathers, etc. only because teeth exist. The method used to make teeth is the same method the body uses to make all of these other important skill structures.

This chapter, just like the rest, reemphasizes how connected living things are. As Shubin simply puts, organisms are just "variations on a theme."

- Aarti Kumar