Did you know that chimp strength is three to five times bigger than that of humans, even though they are on average physically smaller than us? Scientific American explains why chimps have such super strength relative to us.
Studies have shown that muscle control is an important factor in determining strength. Chimps have less gray matter than humans do. Gray matter is the part of the nervous system that contains the nerves responsible for controlling motion. These branch out from the spine into the muscles to control individual muscle fibers. Some neurons can contact many muscle fibers at once. This allows all the muscles to contract at once, creating gross motor skills like jumping. Some neurons contact only a few fibers. These resulting muscle contractions don’t have a lot of power, but they are a lot more precise. Chimps have fewer motor neurons; therefore, their motor neurons are more likely to be dedicated to large motor units (power but not precision). In contrast, humans have ample motor neurons, which give us greater dexterity but less strength.