In this chapter Shubin goes for a humorous approach and does fairly well, considering he's talking about the inside of a skull. We learn all about the layout of our brain and how it is similar to every other animal on earth, specifically sharks. Although he brings up many persuasive arguments, I feel like he is leaving out a lot of important differences.
Chapter 6: The Best-Laid (Body) Plans
It's weird to think that we started off as a ball of cells that end up a tube with three germ layers that then go on to create every single one of our organs. Whoa... Mangold's experiment with moving the small patch of tissue in the embryo and making twins was mind blowing! First of all I cannot imagine how difficult and experiment it must have been and then to think a tiny bit of cells created a whole new living thing! I understand why his experiment was one of the most important in embryology. I think the most important evidence for Shubin was the head to tail organizer genes called Hox. The fact that scientists could find versions of the Hox genes in every animal with a body really did show me how closely connected every animal is.
Chapter 7: Adventures in Bodybuilding
So right at the start of this chapter I was intrigued. That experiment sounded so cool! I think we should do it! :D Anyways... I liked the way Shubin made the ways we are different from every animal in the world so simple. "Our body looks different from that of a jellyfish because of the way our cells attach to one another, the ways they communicate, and the different materials they make"(117). Way to make us feel special. So the analogy of an "earth year" totally freaked me out and then that little time scale... Just wow. So the Precambrian discovers( the little disk bodies) told us the "when" bodies were formed. Shubin begins to explain our body's structure as if we were machines. I wonder if when he looks at a skeleton he thinks: machine? I sure don't. In conclusion, microbes had all the tools to build bodies through their developing ways of interacting with their environment and each other. The important stuff always comes down to the relationships between cells.
Chapter 8: Making Scents
I liked the beginning of this chapter where Shubin talks about his love of fossils. I really admire his passion for his studies. At first I didn't really see how this chapter about noses could be important until he described how smelling has "[...] a profound impact on the way we perceive our world"(140). When he shows us our history of smell though fish, amphibians, and mammals it is quite interesting the way we have modified genes of a jawless fish in out "extra" olfactory genes.
Chapter 9: Vision
The story at the beginning of this chapter acts as a really good hook. How cool for him to have stumbled upon something so rare. So for the role of our eyes to be capturing light in ways that can be processed as an image in the brain, the diagram on page 151 was really helpful in showing the evolution of the sharpness of our vision. To help understand the relationship between the structures of our eyes, Shubin explains in three different ways. First was the light-gathering molecules that every animal has despite the variety of photoreceptor organs. All the light-gathering molecules change shape in the light and recharge in the dark to go back to their normal state. For the second relationship he looks at the tissues that differ between vertebrates and invertebrates. This part didn't seem to be a very strong point due to the fact that the fossil record did not account much of eyes or tissue... The third relationship he described was the similarities in all animal's eye's DNA sequences. The experiments they did with those new discoveries grossed me out. Aren't flies gross enough without being mutated?!
Chapter 10: Ears
Usually when Shubin talks about the inside of a skull it freaks me out, but when he described the inner ear bone it sounded beautiful. Although our external ear only connects us to mammals it is the inside of our ears that connect us to with sharks and bony fish. Mammals have three bones, reptiles and amphibians have only one, and fish have none. So even though shark's ear bones and a human's ear bones look and function completely different they "[...] have similar developmental origins and patterns of innervation"(162). I really liked how towards the end of the chapter Shubin discussed one of my favorite and least favorite animals, the boxy jellyfish. The similarities in the relationships of our eyes and ears in the box jellyfish and humans was pretty crazy, but it made quite a lot of sense.
Chapter 11: The Meaning of it All
Oh Shubin, he had to try and make a funny exit. I like his example of the bozo family tree. And the biological "law of everything" pretty much sums up what he was trying to say in chapters one through ten. Every living thing had a parent. I really liked how he left the reader with one last question: where do our lineages stop?
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