Chapters 8-11

Chapter 8
Shubin discusses our noses' role and the way that smell is transferred to the brain and deciphered as different odors. I liked that Shubin compared smell to a chord, showing that odor is the product of signals from lots of receptors keyed to different odor molecules. I found it interesting when he mentioned that our sense of smell shows our history as amphibians, mammals, and fish. I didn't realize that our noses are witnesses to our past and the animals we originate from.
Chapter 9
When Shubin started talking about the structure of our eyes in the beginning of the chapter, I wondered how eyes could be preserved as fossils. However, he explains that we must understand the relationship between different structures of eyes in order to understand the history of our eyes. I found it very interesting that Shubin and other scientists studied the molecules that gathered light, different tissues that are used to see, and the genes that comprise of the eye.
Chapter 10
Shubin starts off this chapter breaking the ear down into three parts; external, middle, and internal. He mentions the three bones that consist of the middle ear, and explained how they showed how mammals and reptiiles are related. I liked the diagrams that Shubin provided to show the transformation from fish to amphibian, amphibian to reptile, and finally, reptile to mammals. I thought it was interesting when Shubin mentioned the fluid-filled sacs located in our inner ears because I didn't realize that they could tell the brain what was happening to our bodies. It was good to see that this structure could be seen on the skin of underdeveloped fish. This reflection made a connection between humans and primitive life forms.
Chapter 11
Shubin mentions the law describing how every organism has parents. He also states that we are all modified versions and that this descent of modification can show how we connect to the rest of life. I was able to understand why Shubin wanted to decipher these lineages, and why he felt that a pattern could be discovered. I felt that this chapter was a very effective way for Shubin to sum up all that he discussed and shared in the previous chapters, and I liked to see how everything fit together in the end. Shubin also goes on to talk about different diseases that humans suffer and endure, and how they are somewhat related to our past. Overall, Shubin shares many discoveries with his readers, showing that our history can be studied in order to help us live healthier and longer lives in the future. I feel lucky to have learned so much throught this amazing journey that I have been a part of.