This was an interesting exercise. I didn’t know whether to start with thinking about building systems or biological systems first. I decided to start with the building systems, and the first one that immediately came to mind was the structural frame. Of course the obvious analogy here is the skeletal system of animals. This is interesting because in places, like the Bay Area, where structural systems are exposed to seismic loads the system needs to be able to respond well, just like an animal’s skeletal system must be able to respond well to the movement of an animal.