MI-14: Viki files her nails

Here we see Viki filing her nails down. Keith Hayes likely recorded this rather ordinary event to demonstrate how skilled chimpanzees are at motor activities: Filing nails down requires precise movement. Viki is also very intent on her task, and we notice that she uses her right hand to hold the file. Chimpanzees have a preferred hand, just like people do, but about half are left-handed and half are right-handed.