Chapter 5 - Getting Ahead

This chapter was very captivating and entertaining. I appreciated the fact that Shubin took the great complexity of the head and turned it into something easy and interesting to read, by breaking the process of the head into small parts and going step by step. When Shubin talked about the trigeminal nerve and the facial nerve, I found it easy to understand because their function is so simple: to carry information about both sensation and action. The other day my dad was telling me about this program he watched on MSNBC. On the program there was a man who was tested with a lie detector and it was evident that the man was lying because of his facial expressions. Whenever the reporter asked the man a question, his face would get red and sweaty and his eyes would get red. This reveals that the man was untruthful from the way he reacted to the questions and his emotions. Facial expressions reveal everything about a person's mood and attitude.

I really enjoyed this quote, "If you want to understand the wiring and plumbing in my building, you have to understand its history, how it was renovated for each new generation of scientists. My head has a long history also, and that history explains complicated nerves like the trigeminal and the facial" (pg.86). This quote reveals that we should dig deeper in life to understand the origin and past of our head or other important things. We have to understand where everything started off in life and how it was developed. I really liked when Shubin was talking about the embryos and then was kind enough to distinguish the first, second, third, and fourth arch tissues from each other. This really helped me understand the difference between these tissues and their functions. The picture on pg. 88 was very helpful which explained "if we follow the gill arches from an embryo to an adult, we can trace the origins of jaws, ears, larynx, and throat." The arches also have another purpose they reveal our connection with sharks. By looking at the first arch of humans and sharks, a similar trait is found which are the jaws. I was really excited when Shubin said we had an inner shark! Yay! Another animal we are related to!