 It has however been suggested that knuckle-walking evolved independently and separately in Pan and gorillas and so was not present in the human ancestors.
<fluency>  It has however been suggested that knuckle-walking evolved independently and separately in Pan and gorillas and so was not present in the human ancestors.
 It has however been suggested that knuckle-walking evolved independently and separately in Pan and Gorilla, so was not present in the human ancestors.