What regions in the cerebral cortex are known to be involved in movement? How do these areas contribute to the production of motor behavior?

Located at approximately mid-brain and at the very back of the temporal lobe is the motor cortex, which is the area of the cerebral cortex that controls voluntary movements (Dubuc, 2008). Within the motor cortex are two sections that work together and separately to create fluid and complete movements. These sections consist of the primary motor cortex (area 4) and the supplementary motor area (SMA or area 6) (Dubuc, 2008). The primary motor cortex of the brain contributes to voluntary movement through generating signals to the opposite side of the body, letting the muscles know that it is time to move (Brain Connection, 2009). Since this action is simple, this area of the brain is considered a part of lower evolution, in that it evolved early in the species. The supplementary motor area is an area that is more involved in understanding spatial awareness, learned movements, and calculating strength and force to move an object. Since these actions are more complicated than simply moving a part of the body, this section of the brain is considered more advanced in that it evolved later in the species.

Do you know when we found that it was evolved? Or could it just be a section that we didn't know about because we didn't have the capability to find it early on? Are there other sections of the brain with this case of evolving?