Your Inner Fish

Your Inner Fish: A Review of Chapter 4 In Your Inner Fish, a book about the study of evolution in mammals, chapter four is dedicated to the study of teeth. Neil Shubin is explicit in his insistence that teeth are extremely important when studying evolution of the human body. He uses three main points to explain this to the reader. First, through the function of teeth. Then by revealing the anatomy of teeth. And finally by discussing tooth-to-tooth occlusion. Teeth are used to manipulate larger objects so that they may fit into a smaller mouth. Shubin writes ”Mouths are only so big, and teeth enable creatures to eat things that are bigger than their mouths” (Shubin 60). Without teeth creatures would have a smaller variety of options when it came to food choices. Bigger fish could only eat smaller fish and so on. As explained by Shubin “… teeth can be the great equalizer: smaller fish can munch on bigger fish if they have good teeth” (Shubin 60). So we derive from this that teeth can play an important role in the food chain and thus in evolution. However, teeth play a more important part than this. By studying the anatomy of teeth many secrets can be revealed about ancient reptiles and mammals. For instance, Shubin relates that “The bumps, pits and ridges on teeth often reflect the diet” (Shubin 60). By knowing the diet of an ancient creature, it is reasonable to see how a paleontologist and evolutionist can follow the emergence of the omnivore over the carnivore and herbivore. And the hardness of teeth make it the “best-preserved animal we find in the fossil record for many time periods” (Shubin 61). This clue to these ancient animal’s diets can “give us a good window on how different ways of feeding came about” (Shubin 61). So, the shape of the teeth and the general mineral make-up both contribute to the usefulness of teeth to the scientist.

Still it remains that the tooth-to tooth occlusion is an imperative discovery when shaping the history of the human body.

Citations: Shubin, Neil. Your Inner Fish. Pantheon books, New York. 2008.