Ch. 8, 9, 10, 11

Ch. 8: Making Scents
Shubin made it really easy to relate to everything he was writing. When he was describing how to extract DNA by taking a handful of tissue from a plant, adding some salt, blending it, adding some dish soap, and finally adding meat tenderizer; I remembered this from an experiment I had done in my 8th grade science class. It was fascinating to discover that, "Our sense of smell allows us to discriminate among five thousand to ten thousand odors" (141). His analogies such as the lock being the odor molecule and the key being the receptor on the nerve cell really helped me visualize how smell really works. He stated that, "As in fish, amphibians, reptiles, mammals, and birds, much of our sense of smell is housed inside our skull" (142). He always finds some way to find similarities between humans and other creatures. I never knew that there were two types of ways someone can smell: lampreys and hagfish take odors from water while us mammals and some other creatures take it from the air we breath.

Ch. 9: Vision
Shubin made it obvious that many eyes don't make it into the fossil record because usually only bones, teeth, and scales fossilize and are preserved. Some general knowledge I knew about how the brain processes images was shown in this chapter: "[...]the role of the eye is to capture light in a way that it can be carried to the brain for processing as an image" (149). This fact didn't make me feel so clueless as how to compare humans to other creatures. The diagram of the muffin on page 151 really helped me visualize how the brain processes an image. It was interesting to know that there are light gathering cells and when the molecules, "[...]absorbs lights, it changes shape and breaks into two parts. One part is derived from vitamin A, the other from a protein known as opsin" (152). I never knew that, "We can even trace some major events in the history of our eyes by examining opsins in different animals" (153). I didn't even know that was possible. It was hightly interesting to know that if you took a gene that was off in a mouse and therefore some part of the eye was not there, you could turn it on in a fly and an eye would grow out of the area where you turned the gene on.

Ch. 10: Ears
I already knew that there was a gel like substance inside your ear and you have a three part bone structure: the malleus, the incus, and the stapes. It was unbelievable to me that the stapes from the second arch was a shrunk down version of a jaw in reptiles. I was just as shocked as German anatomist Karl Reichert but he had to conclude that, "[...]the same gill arch that formed part of the jaw of a reptile formed ear bones in mammals" (160). I knew that drinking too much alcohol plays around with your vision but I didn't know that was caused by something going on in your ear. In this chapter it is revealed that, "[...]alcohol diffuses from our blood into the gel of the inner ear [...]as the alcohol enters, so the gel inside our ear swirls [...]Our hair cells are stimulated and our brain thinks we are moving" (168). It all makes sense now through this chapter.

Ch. 11: The Meaning of it All
The example of the bozo family tree helped me realize that we are all connected to another creature whether it be that we both have ears, four limbs, hair, or mammary glands. This chapter made me realize that our relation to another creature is not absolute because we may share more similarities to one creature than another. Our similarity to one creature may be more recent than another. I like how Shubin refers back to the past chapters when he says, "From Chapter 1 through Chapter 10, we have shown that deep similarities exist between creatures living today and those long deceased -- ancient worms, living sponges, and various kinds of fish" (181). Everything is summarized in this chapter and it makes more sense to how we all are related to one another in some way. Also, some new information is introduced to us that all these modifications from the past to the future come with a price. It is stated in the book that our ancestors were "active" and today we their descendants are not so active and therefore we introduce heart diseases and other diseases to ourselves. I didn't know that hiccups came from tadpoles and passed on to us. Tadpoles closed their glottis in order to prevent water from entering their lungs and that passed onto us when we take an abrupt intake of air which causes us to have "hiccups". This book has truly changed my point of view on how I viewed other creatures. It has made me realize that we are all connected in one way or another and we always will be.