Chapter Six: The Best-Laid (Body) Plans

This chapter was basically about embryos and genes that make up living creatures. Just as he correlated humans to animals in previous chapters, Shubin again claimed that like us, fish, lizards, and other species have bodies that are symmetrical with a front/back, top/bottom, and left/right. With the idea of embryo, I've learned that species end up looking different, but start from a similar place. In spite of this, I discovered that three layers consisting of ectoderm, endoderm, and medoderm form the same structure in every species and are significant in revealing fundamental patterns of life. And along with the three layers, genes also play crucial roles during a development as it develops the body axis and interacts with other genes rather than acting alone. Towards the end of the chapter, I was really amazed to know that sea anemones share a common trait as humans: a front and a back set up by same genes.