die meisten kennen sicherlich diese studie http://www.mecca.org/~rporter/PARROTS/grey_al.html INTRODUCTION Although parrots are not often mentioned in discussions about nonhuman intelligence, much data exist to suggest that psittacids are among the more intelligent animal species. During the 1940's and 1950's, for example, laboratory researchers in Europe demonstrated that Grey parrots could learn the kinds of symbolic and conceptual tasks that are generally considered as pre- or co-requisites for complex cognitive and communicative skills (reviews in Pepperberg1,2). More recently, field studies have reported behaviors that, when observed in nonhuman primates, are considered as evidence for human-like intelligence. Such behaviors include cooperative alarm signaling ("sentinel behavior") in flocks of Indigo macaws (Anodorhynchus leari)3 and individual recognition in Bahamian Amazons (Amazona leucocephala bahamensis).4 Another sign of intelligence, thought to be absent in most nonhuman animals, is the ability to engage in complex, meaningful communication; only recently has the general perception of parrots as mindless mimics been shown to be incorrect.2 Prior to the 1970's, researchers lacked knowledge of psittacine communication in the wild, and assumed that natural behaviors would not differ greatly from what had been observed in captivity: the ability of parrots to reproduce, with great accuracy, sounds such as those of human speech,5 but little (if any) ability to use these vocalizations in a meaningful way.6 The few studies in the 1950's and 1960's to challenge these perceptions -- e.g., Mowrer's attempts to teach mimetic birds to engage in meaningful communication with humans -- used standard psychological laboratory training paradigms and were not successful.7,8 Since the 1970's however, researchers working both in the field and in aviary settings have provided data to indicate that natural psittacine vocalizations might indeed be meaningful: Vocalizations appear to mediate social interactions between mated pairs and among flock members, and not only the physical structure but also the appropriate use of these vocalizations seems to be learned.3,4,9 Such findings on sophisticated vocal behaviors, when taken in conjunction with the data on complex problem-solving abilities, suggested that the psychologists' failures to achieve meaningful communication with their birds might be due to inappropriate training techniques, rather than to any inherent lack of intelligence in the psittacine subjects.1 My research has been a test of this premise. Starting in the late 1970's, I developed techniques that integrated the experimental rigor of the laboratory with what little was then known about psittacine communication in nature; I also borrowed ideas from projects designed to examine the bases for human social learning (reviews in Pepperberg2,9,10). I have used these techniques successfully to establish a form of interspecies communication with an African Grey parrot. The existence of such behavior demonstrates that at least one avian species is capable of interactive, referential communication. My students and I, moreover, use the ability to communicate to test the extent of this bird's intelligence. The following sections provide details of the procedures and a short summary of the results. THE SUBJECT OF THE STUDY The experimental subject, an African Grey parrot named Alex, has been the focus of a study on interspecies communication and avian intelligence since June, 1977. At the start of the project he was approximately 13 months old and had received no prior formal vocal instruction. He has free access to the laboratory room while trainers are present (~ 8 hrs/day), but is confined at other times to a cage (~62x62x73 cm) and the desk upon which it rests. Water and a standard psittacine seed mix (sunflower seeds, dried corn, oats, etc.) are continuously available throughout the day; fresh fruits, vegetables, specialty nuts (cashews, pecans, almonds, walnuts), and toys are used in training and are provided at his vocal requests. RATIONALE FOR USING INTERSPECIES COMMUNICATION TO STUDY INTELLIGENT BEHAVIORS Interspecies communication is a particularly powerful tool for assessing intelligence because it provides a simple, direct means for testing subjects. Unlike other systems, a two-way communication code (1) enables researchers to query their animal subjects in as direct a manner as they now query human participants in related studies; (2) enables researchers to communicate to their subjects, in the most efficient way possible, the precise nature of the questions being asked; (3) takes into account the animals' natural predispositions by providing a social context not entirely unlike their field situation;11 (4) allows comparisons not only between humans and other animals but also among widely-divergent animal species; (5) is an open, arbitrary system in which subtle variations create an enormous variety of signals that can be used to examine the nature as well as the ex-tent of the information perceived by the subject; (5) allows rigorous testing because the subjects can be required to choose their responses from their entire repertoire rather than from the subset relevant only to the topic of a particular question; and (6) is flexible enough to allow subjects to respond in novel and possibly innovative ways that may demonstrate intelligence beyond that required by the intended task (from Pepperberg12,13). TRAINING TECHNIQUES 1. Use of Intrinsic Rewards (excerpted from Pepperberg1,2,10) My students and I use several techniques to teach the parrot meaningful communication, but one feature all have in common is the consistent, exclusive use of intrinsic reinforcers -- i.e., when we teach Alex labels for particular items, his reward for producing the correct label is the object to which the label or concept refers. Thus, if Alex correctly identifies a cork, that is what he receives. This procedure insures, at all times, and at every interaction, the closest possible association of the label or concept to be learned and the object or task to which it refers.1,14 In contrast, programs such as Mowrer's relied on extrinsic rewards.7 Thus, on the few occasions when his subjects correctly labeled food or nonfood items, or made appropriate responses to various specific commands, they were rewarded with a single, particular favored food that neither directly related to, nor varied with, the label or concept being taught. I believe that extrinsic rewards may actually act to delay label or concept acquisition by confounding the label of the exemplar or concept to be learned with that of the food reward.14,15,16 Alex therefore never receives extrinsic rewards. On occasion, Alex may receive a more general form of reward: Because it is sometimes difficult to maintain his interest in the set of objects that are being used to train a particular concept, he may be rewarded with the right to request vocally a more desirable item than the one he has identified ("I want X"). Such a protocol provides some flexibility but maintains the referentiality of the reward. Alex will never, for example, automatically receive a slice of banana when he identifies a cork. The banana must specifically be requested ("I want banana"), and trainers will not respond to such a request until the appropriate prior task is completed.17 2. The Model/Rival (M/R) Technique (excerpted from Pepperberg1,2,10) The primary training system, called the model/rival, or M/R technique, is based on a protocol developed by Todt, an ethologist interested in social learning in parrots.18 Todt's procedures, in turn, derived much from the work of Bandura, who studied the effects of social modeling on learning in humans.19 The M/R procedure involves three-way interactions between two competent human speakers and the avian student. M/R training is used primarily to introduce new labels and concepts, but also aids in shaping correct pronunciation. During M/R training, humans demonstrate to the bird the types of interactive responses that are to be learned. A typical interaction proceeds as follows: Alex is seated on his gym, his cage, or the back of a chair, and observes two humans handling one or more objects in which he has already demonstrated an interest. In the presence of the bird, one human acts as a trainer of the second human. The trainer presents the object(s), asks questions about the object(s) (e.g., "What's here?", "What color?", "What shape?"), and gives the human model praise and the object(s) in question as a reward for a correct answer. Disapproval for incorrect responses (erroneous answers that are similar to those being made by the bird at the time: unclear vocalizations, partial identifications, etc.) is demonstrated by scolding and temporarily removing the object(s) from sight. Thus the second human not only acts as a model for the bird's responses and as a rival for the trainer's attention, but also allows the parrot to observe the effects of an error: The model is asked to try again or talk more clearly if the response was (deliberately) incorrect or garbled.