Chapter 6 discussion

In chapter six of, Your Inner Fish, it talks about the relationship between DNA, Embryology, and germ layers. It first mentions the scientist Karl Ernst Von Baer who discovered that organs are derived from 3 developing layers in the embryo. These three germ layers, the ectoderm, endoderm, and mesoderm, are within all animals, and are where organs are created from.

In this picture, you can see how each layer corresponds to a different set of organs.

What controls the body plan is a small piece of tissue called the organizer. It is also revealed that DNA controls the organizer, and therefore controls the body plan. This connects all there concepts to evolution, and how our bodies change over time.