Multicellular organisms like us have very complex and elaborate morphologies. We can use it to do a variety of things, and interestingly, people can seriously consider the question of what they are. However, even such a complex organism is just a single sphere called an egg at the beginning of its life. The ultimate simple form automatically changes over time into the complex form described above. If you were to use clay to create an image of a "thinking person," many would first determine the proportion of clay to be allocated to the head, torso, and feet.
In fact, the design style (body plan) used by living organisms to create the body does exactly the same way. By repeating simple rules, complex things can be created. In this class, you will learn the body plan that creatures actually use.