More recently,psychologists Patricia Greenfield and Sue Savage-Rumbaugh studied a different species of chimp,a male bonobo or pygmy chimpanzee named Kanzi.Thay used the same plastic symbols and computer keyboard that were used with Lana.Thay claimed that Kanzi not only learned,but also invented,grammatical rules.One rule they described is the use of asymbol designating an object such as "dog"followed by a symbol meaning "go" After combining these symbol,Kanzi would then go to an area where dogs were located to play with them.Greenfield and Savage-Rumbaugh claimed that this "ordering"rule was not an imitation of his caretakers' utterances,who they said used an opposite ordering,in which "go"was followed by "dog