Chapters 8-11

Making Scents

Many interesting things were revealed in this chapter. Aside from the simple-at home way to extract DNA from bodies with just soap meat tenderizer and alcohol (which by the way I intend to try) I also found it fascinating how humans as well as primates have developed to become beings that have traded smell for sight. We have many more "extra" genes used for smelling however, over time we have irrevocably traded better sight for those now unused genes. Alex and Buck's three major assumptions and their accuracy in their hypothesizes and experiments surprised me. Not only that, but on top of that they as well found the exact percent of genome that is devoted to genes for detecting different odors. This chapter really made me realize how important our sense of smell is to us and how we have evolved from the humans we are today.

Vision

In this chapter it explained about the different parts of the eye and their functions as well as the other types of eyes that different types of animals have such as photo receptor organs in invertebrate animals, compound eyes in various insects, as well as our camera-type eye. the role of the eye is to capture light in a certain way so that our brains can turn that light into an image that we can recognize. Our eyes do this using a cornea, iris, lens, as well as the retina. These different parts of our eyes work together so that we can accurately see images all around us. The most interesting thing to me was the fact that scientists have identified the gene, Pax 6, which can produce creatures with small eyes or no eyes at all. It also came as a surprise to me how Walter Gehring took the eyeless gene from Mildren Hoge and could produce flies with eyes in all different places.

Ears

In this chapter, it mentioned the different parts of the ear-explaining the functions of the external, middle, and inner ear. Pinna was one of the new terms I learned during this chapter which is the flap of the external ear-its unique in only mammals. What caught my eye the most in this part of the book is Karl Reichert’s hypothesis that the two ear bones of mammals correspond to pieces of the jaw in reptiles. Although this was just a hypothesis it was later supported by Richard Owen’s discovery of fossils found in South Africa supporting the transition from a jaw in a reptile to ear bones in mammals. This struck me because it really hit me how time can really change and mutate one thing so that it can help another animal adapt better to their environment. Another interesting thing in this chapter was how the box jellyfish had neither Pax 6 nor Pax 2 and it’s connection to mammals.

The Meaning of It All

I couldn't believe this was the last chapter of the book. It seemed as if just yesterday I had started reading Your Inner Fish and begun blogging. This chapter was really an accolade to the whole book. The way it tied all that had been said in the previous chapters was really satisfying. To learn how the lineage of species had begun and our ties to all different kinds of animals really surprised me. Who knew that we could be related to turtles, fish, and even worms??