Getting Ahead: Chapter 5

This chapter was refreshing (HAHA what a joke, how can a chapter starting off with a bisected head be refreshing?! ); however, it was refreshing because it took a break away from the derivation of our history from dry fossils and instead, derived from a more wet aspect (gills). Without thinking much about it, our head and its history seem overly complex, but the way Shubin points out stuff that we already know from common sense (no one starts off life with a pre-formed head) and teaches us the stuff we don't know (such as the arches) makes understanding the development of our heads on a much simpler level.

I learned that the head has 4 arches, and each arch is responsible for developing a certain part of our face. By knowing the function of these 4 arches, scientists can alter the genetic code to do experiments and see what kind of changes result when they interfere with the development of our facial features/functions.

However, there is one thing that is consistently bothering me while reading this book. Shubin traces the development of our body (so far he's traced the history of our limbs, teeth and head) and I understand that the basic blueprint of our bodies comes from ancient creatures, but how? Is the answer simply just "we started out as very simple and basic creatures, but in order to adapt to the increasingly competitive and harsh world and the environment in which we live (or have to adapt to live in because of competition), our bodily structures have changed in order to facilitate survival"? I think I have the general idea, I just need to think about it a little everyday and let it sink in.

Anyways, I think this chapter is interesting in a sense that it finally helped me realized what a composite element humans are. Seriously, I'd never come to think that the arches that forms our jaws/ears correlate directly to the formation of gills in sharks.... *so that means... if we change the genetic code that forms our jaws/ears, we have gills too? :D* Being the land dwellers that we are makes it seem out of this world that the basic blueprints of our "landly" features stemmed from fish. Everything is connected to fish (because the world was once submerged in water). I finally understand it now! It IS a very general and broad concept and I have a feeling it will slip out of my mind very easily. The key to not letting all this new information slipping out is by connecting the current chapter to the previous chapters.

- ejay yuan