Just today, I've learned something. When I was on Deviant Art, someone told me that it's almost true that the rib cage and the pelvis are oval shaped. Here's the thing, the rib cage is more of a squashed oval with distinct sides. For the pelvis, the front and back are flat and the sides are distinct. since I don't know the word distinct, I'm glad to have this information of the rib cage and pelvis. Enjoy the advice!