Chapter 6: The Best-Laid (Body) Plans

I really was amazed by this chapter because this one explained how embryos of different creatures are all similar during the beginning stage. I never thought that a human embryo would look similar to that of a chicken. As Shubin explains in page 99, all organs in the chicken can be traced to one of three layers of tissue in the developing embryo called the germ layers. Knowing that these layers form all the parts of the body was very interesting, not to mention that this applies to humans also. Furthermore, the similarity of these germ layers in all fish, reptile, and mammal was even more shocking, learning how every heart of every species formed from the same layer. And also the brain from same layer. Moreover, the diagram in page 103 really amazed me, learning that this picture represents us humans during our primitive form. The formation of tube within a tube along with the three germ layers were bit confusing to understand at first but as the chapter went along, I began to understand the concept behind it. Overall, this chapter was very intriguing, learning of another similarity that humans share with other species.

Chapter 6:The Best-Laid(Body) Plans

Another chapter of comparing humans to other creatures, however, chapter 6 was still I was another exiting and interesting chapter. This time i learned how embryos hold the clue compare ourselves to primitive animals. It was amazing to think that "three layers of tissue in the developing embryo" are all the same in every species! It was interesting to learn that each layer gave rise to a specific area like the brain or the heart. The diagrams always help me understand this book more, allowing me to not lose focus. It caught my attention when Shubin described that"flies have a body plan...some mutant flies have limb growing out of their heads." because i always thought of flies as annoying pest in the house sitting on our food and wasn't useful at all. However. they seem to be useful in helping us study their body structure. Another interesting part was about an "inner sea anemone", we seem to have things in common i guess. It's awesome how Shubin connects our bodies with other creatures all the time!

Chapter 6: The Best-Laid (Body) Plans

I really liked this chapter from its start. I was captivated from how he kept emphasizing the basic body structure while still marveling at each species' complex anatomy. All the experiments he described were incredible to me. For example, von Baer's experiments discovered that every animal organ originated from the three germ layers. I was a little bewildered at this; especially with all of Shubin's vivid descriptions of the complexity of our bodies in the previous chapters, I never would have thought that it was so basic. I did get a little lost, however, when he was describing the development of the human embryo, but his illustrations were both engaging and informative.
The thing about this that I found the most amazing throughout this chapter and maybe even this whole book so far was Shubin's connection of humans with sea anemones with the simple knowledge of symmetry. I always considered sea anemones and jellyfish to be blobs of animals, it amazed me that we could be even distinctly related!

Chapter Six: The Best-Laid (Body) Plans

One part that caught my attention was when Shubin explained that almost all animals, including human, share"von Baer's three germ layer" structure: The ectoderm, the endoderm, and the mesoderm. These important layers form many of the inner structures of our body, such as the digestive organs, skeletons, and muscles. Another interesting part was the comparison of flies and humans,"versions of hox genes appear in every animal with a body. The eight genes which contain the homobox, responsible for genetic mutations, hox genes are found in many creatures, in different numbers." The only difference, in Shubin's opinion, between flies and men is that flies have one set of eight hox genes while humans have four sets of hox genes.

Shubin's comparison between humans and creatures such as fish, amphibians, and flies, was surprising enough; Shubin introduced a new comparison, between human and jellyfish. I was shocked when i read about the author's experiment of the gene, noggins. "Take the product of noggin from a sea anemone and inject it into a frog embryo. The result: a frog with extra back structures, almost the same result as if the frog were injected with its own noggin." (124). This chapter was full of strange comparisons between humans and unexpected animals, but i learned a lot about common inner structures of many creatures.

Chapter 6: The Best-Laid Body Plans

It's funny how some species have the same design, yet they all have different sizes and shapes. Sadly, when it comes to primitive animals, no human structure can match. A few pages into this chapter, when Shubin started talking about blastocysts and how it's part of the process of our development, I was all ears. I have a penchant when it comes to learning about the formation of our entire body and how it goes through many stages of development, yet it seems pretty grotesque to cut ourselves open and see a tube within a tube. I can't even imagine how highly intricate our developing stages are.

Towards the middle of the chapter, the book starts talking about flies. To me flies are annoying with their persistent buzzing and I would always try to swap them with a fly swapper; However, a simple fly contains the mutation in genes that give us clues about the genes active in human embryos. Who knew they were so important.

My favorite part of this chapter was at the very end when Shubin mentions how we are compared to animals with bodies, but how do we compare ourselves to animals with no bodies? Hmm...

-Mitasha Sujan

Ch. 6: The Best-Laid (Body) PlansAt a

At first, it was difficult for me to grasp the meaning of this chapter and all the information given, but after reading over, i seem to understand a bit of what Shubin was trying to get to us. It was interesting how Pander's three layers are all the same in every species. No matter how different an animal may be, as tiny embryos they all went through the same stages of development. I started to get very confused when Shubin started talking about our human embryo and the stages of development. He had gone into depth and started telling us how we first look like a fluid filled balloon then a frisbee and continued to explain so much. I did not understand the significance of his explanations and was not sure where he was trying to go with this. What I found entertaining was when Shubin talked about the sea anemones and animals that have no nerve cord. For example, creatures such as jellyfish, corals, and sea anemones have a opening that serves as a mouth but ALSO to expel waste. That is pretty disturbing. It amazed me how Shubin tries to compare human bodies to every living creature out there and find a connection, even with jellyfish!

8) Making Scents

This chapter made scents and was fairly easy to understand compared to others. Okay, I'll stop that now.

With this chapter, I was able to learn the science behind why no one wants to use the running machines next to the one I'm using probably because of our smell receptors (I'm kidding). And probably why a woman gave me a breath mint the other day (actually happened... but it was out of kindness. If anything, she gave me candy too.).

And as I saw it coming, fishes. Them fishes I eat everyday have the same smelling systems as us, cool, like that diagram in this chapter he put, from jawless fish to us.

And genes? I never knew that 3% of our genome is dedicated to smell but we don't use it all... because we traded it for vision... Guess why dogs have better smelling than us... and why we use their "emphasized" smelling for tasks such as tracking escapees... I've been watching too much Breakout (prison reality show on National Geographic) lately...

Makes sense... makes a lot of scents.

Okay I'm done.

- Keith Choison