Hockenbury Discovering Psychology 5th txtbk

292 CHAPTER 7 Thinking, Language, and IntelligenceVervet Monkeys Vervet monkeyssound different alarm callsfor different kinds of predators.The “leopard” call sends thetroop into the trees to avoidleopards and other groundpredators. In response to the“eagle” call, the monkeys lookup and take cover in bushes tohide from aerial predators.Sue Savage-Rumbaugh withKanzi Kanzi, a bonobo, communicatesby pressing symbolson a computer keyboard. Kanziuses the symbols to communicaterequests and intentions—and even, when alone, to“talk” to himself. Kanzi now residesat the Great Ape Trust inDes Moines, Iowa, in a colonywith seven other bonobos,where study of primate cognitioncontinues in a naturalenvironment (Segerdahl & others,2006). To learn more aboutthe Great Ape Trust sanctuaryand the orangutans, bonobos,and research psychologists—includingSavage-Rumbaugh—who live and work there, visitthe Web site at www.Great-ApeTrust.org.Clearly, animals communicate with one another,but are they capable of mastering language?Some of the most promising results havecome from the research of psychologists SueSavage-Rumbaugh and Duane Rumbaugh (Lyn& others, 2006). These researchers are workingwith a rare chimpanzee species called thebonobo. In the mid-1980s, they taught a femalebonobo, named Matata, to press symbols on acomputer keyboard. Although Matata did notlearn many symbols, her infant son, Kanzi, appearedto learn how to use the keyboard simplyfrom watching his mother and her caretakers(Savage-Rumbaugh & Lewin, 1994).Along with learning symbols, Kanzi also comprehendsspoken English. Altogether, Kanzi understandsmore than 500 spoken English words.And, Kanzi can respond to new, complex spokencommands, such as “Put the ball on the pineneedles,” and “Can you go scare Matata withthe mask?” (Segerdahl & others, 2006). Because these spoken commands are madeby an assistant out of Kanzi’s view, he cannot be responding to nonverbal cues.Kanzi also seems to demonstrate an elementary understanding of syntax. He isable to respond correctly to commands whose meaning is determined by wordorder. For example, using a toy dog and toy snake, he responds appropriately tosuch commands as “Make the dog bite the snake” and “Make the snake bite thedog.” Kanzi seems to demonstrate a level of language comprehension that isroughly equivalent to that of a 2 1 ⁄ 2 -year-old human child (Lyn & others, 2006).Research evidence suggests that nonprimates also can acquire limited aspects oflanguage. For example, Louis Herman and his coworkers (1993, 2002) have trainedbottle-nosed dolphins to respond to sounds and gestures, each of which stands fora word. This artificial language incorporates syntax rules, such as those that governword order.Finally, consider Alex, an African gray parrot. Trained by Irene Pepperberg(1993, 2000), Alex could answer spoken questions with spoken words. By the timeof his death in 2007, Alex could identify 50 different objects, 7 colors, 5 shapes,and quantities up to 7. He could accurately answer questions about the color andnumber of objects, and could categorize objects by color, shape, and material,which suggested that he comprehended simple concepts (Pepperberg, 2007). Alexalso used many simple phrases, such as “Come here” and “How many?” He couldeven indicate where he wanted to be taken by saying, “Want to go knee” (to sit ona knee) or “Want to go back.”When animal language research beganin the 1960s and 1970s, some criticscontended that primates were simplyproducing learned responses totheir trainers’ nonverbal cues ratherthan demonstrating true language skills(Terrace, 1985). Over the last twodecades, however, studies conductedunder more carefully controlled conditionshave produced some compellingdemonstrations of animal languagelearning. Nevertheless, even the performanceof primate superstars such asKanzi pales in comparison with thelanguage learning demonstrated by a3-year-old child (Pinker, 1994).