Chapter 8 - 11

Making Scents
Even with new technology to revolutionize the approach to anatomy and developmental biology, fossil and geological records still remain as very effective methods. It's amazing how much information DNA can store in an organism because it shows how far it evolved from the simple non-vertebrae. I find this book interesting because Shubin gave me an experiment to try in my own kitchen, and then he explains how this experiment relates back to what he was talking about. I also didn't know that we could store thousands of different smells on our nerve receptors. The diagrams helped me understand how people are able to smell and distinguish scents. It was interesting when Shubin said that our sense of smell is thanks to fish, amphibians, and mammals.
Vision
First thought I had was that it was very amusing when I saw a Hostess pastry being used in the sight diagram. It's crazy that the light-sensing cells account for seventy percent of all sensory cells in our body. Especially since the eye is very small. I finally know why my vision is basically turned off when I go from the bright living room to my pitch dark room; the light-capturing molecules in my eyes need to recharge for a few minutes before my eyes can modify itself so I can see in the dark more clearly. Another way people are related to other animals is that we all use light-capturing molecules to see. Interestingly enough, color vision first appeared in monkeys that lived in the trees and used the color to distinguish the different fruits and leaves and pick the one that's most nutritious to them.
Ears
When Shubin explained how sound goes into your ear, and I thought his comparison of that with a Rube Goldberg contraption was spot on. Right when the sound wave enters the ear, it begins a cause and effect chain which ultimately ends with us registering the sound. Normally, I would be surprised when Shubin relates our body parts with fishes or other organisms, but after so many convincing evidence and commentary, I'm no longer shocked when he compared our inner ears to sharks and bony fishes. Although mammals have three bones and reptiles and amphibians only have one, the stapes bone is very similar to the one ear bone reptiles and amphibians have. And to sharks and fishes, the stapes bone is similar to their hyomandibula; however it has a different function than the stapes since fishes don't have ears. The Tiktaalik is mentioned again and from it we can see how the hyomandibula gets shorter over time, to the point where it is shifted from its original position and plays a role in hearing. An interesting fact from Shubin would be when a person consumes too much alcohol, it diffuses from the blood to the inner ear; and since it's lighter it makes the person think they're moving even when they're not.
The Meaning of it All
The knowledge Shubin explained throughout the novel, could all be used to understand diseases more, catch criminals, and even trace our family ancestry, and then he said, "... we see the meaning of the fish, worms, and bacteria that lie inside of us" (174 Shubin). Everyone comes from parents and that's where we get our certain features that make us who we are. And since we are are a product from two different people, that's where we inherit certain features from them. By that fact a family tree can be identified by certain features that are passed down. Like most organisms, we have bodies that are composed of cells, and also share a body plan like ours. From having a back bones, and having hads and feet. Then add the features of a big brain, three bone ear, and you get a mammal called humans. Grouping organisms like this allows us to see how alike we are physically to others. Fun fact I learned, people were only "designed" to live up to eighty years, because we are supposed to be moving, and not be immobile. Even talking is not without its "side effects". Sleep apnea and choking are possible danger factors when it comes to the ability to speak. Since we have two passages, we could easily choke if the food goes into the passage where we breathe. Also, if the throat passage collapses, the sleeping person would go through long stretches where they don't even breathe. Another funny thing I found in this chapter is that we share hiccups with tadpoles and fishes.
-Jennifer Ly