An African Grey parrot, previously taught to use vocal English labels to discriminate more than 80 different objects and to respond to questions concerning categorical concepts of color and shape, was trained and tested on relational concepts ofsame anddifferent. The subject, Alex, replied with the correct English categorical label (“color,” “shape,” or “mah-mah” [matter]) when asked “What’s same?” or “What’s different?” about pairs of objects that varied with respect to any combination of attributes. His accuracy was 69.7%–76.6% for pairs of familiar objects not used in training and 82.3%–85% for pairs involving objects whose combinations of colors, shapes, and materials were unfamiliar. Additional trials demonstrated that his responses were based upon the question being posed as well as the attributes of the objects. These findings are discussed in terms of his comprehension of the categories of color, shape, and material and as evidence of his competence in an exceptional (non-species-specific) communication code.
Bandura, A. (1971). Analysis of modeling procedures. In A. Bandura (Ed.),Psychological modeling (pp. 1–62). Chicago: Aldine-Atherton.
Beecher, M. D., Stoddard, P. K., &Loesche, P. (1985). Recognition of parents’ voices by young cliff swallows.Auk,102, 600–605.
Brodigan, D. L., &Peterson, G. B. (1976). Two-choice conditional discrimination performance of pigeons as a function of reward expectancy, prechoice delay, and domesticity.Animal Learning & Behavior,4, 121–124.
Davis, H. (1984). Discrimination of the number three by a raccoon (Procyon lotor).Animal Learning & Behavior,12, 409–413.
Davis, H., &Bradford, S. A. (1986). Counting behavior in rats in a simulated natural environment.Ethology,73, 265–280.
Edwards, C. A., Jagielo, J. A., &Zentall, T. R. (1983). Same/different symbol use by pigeons.Animal Learning & Behavior,11, 349–355.
Essock, S. M., Gill, T. V., &Rumbaugh, D. M. (1977). Language relevant object- and color-naming tasks. In D. M. Rumbaugh (Ed.),Language learning by a chimpanzee (pp. 193–206). New York: Academic Press.
Falls, J. B. (1985). Song matching in Western meadowlarks.Canadian Journal of Zoology,63, 2520–2524.
Falls, J. B., Krebs, J. R., &McGregor, P. K. (1982). Song matching in the great tit (Parus major): The effect of similarity and familiarity.Animal Behavior,30, 997–1009.
Granier-Deferre, C., &Kodratoff, Y. (1986). Iterative and recursive behaviors in chimpanzees during problem solving: A new descriptive model inspired from the artificial intelligence approach.Cahiers de Psychologie Cognitive,6, 483–500.
Herrnstein, R. J. (1984). Objects, categories, and discriminative stimuli. In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds.),Animal cognition (pp. 233–261). Hillsdale, NJ: Erlbaum.
Hülse, S. H., &Cynx, J. (1985). Relative pitch perception is constrained by absolute pitch in songbirds (Mimus, Molothrus, andSturnus).Journal of Comparative Psychology,99, 176–196.
Kamil, A. C. (1984). Adaptation and cognition: Knowing what comes naturally. In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds.),Animal cognition (pp. 533–544). Hillsdale, NJ: Erlbaum.
Kroodsma, D.E. (1979). Vocal dueling among male marsh wrens: Evidence for ritualized expressions of dominance/subordinance.Auk,96, 506–515.
MacPhail, E. M. (1985). Vertebrate intelligence: The null hypothesis.Philosophical Transactions of the Royal Society, Series B,308, 37–51.
Marschark, M. (1983). A code by any other name ....Behavioral & Brain Sciences,6, 151–152.
McClure, M. K., &Helland, J. (1979). A chimpanzee’s use of dimensions in responding same and different.Psychological Record,29, 371–378.
Menzel, E. W., Jr., &Juno, C. (1982). Marmosets (Saguinus fuscicollis): Are learning sets learned?Science,217, 750–752.
Menzel, E. W., Jr., &Juno, C. (1985). Social foraging in marmoset monkeys and the question of intelligence.Philosophical Transactions of the Royal Society, Series B,308, 145–158.
Michael, J., Whitely, P., &Hesse, B. (1983). The pigeon parlance project.VB News,2, 6–9.
Moran, G., Joch, E., & Sorenson, L (1983, June).The response of meerkats (Suricata suncatta)to changes in olfactory cues on established scent posts. Paper presented at the annual meeting of the Animal Behavior Society, Lewisburg, PA.
Mowrer, O. H. (1960).Learning theory and symbolic processes. New York: Wiley.
Park, T. J., &Dooling, R. J. (1985). Perception of species-specific contact calls by budgerigars (Melopsittacus undulatus).Journal of Comparative Psychology,99, 391–402.
Pepperberg, I. M. (1979, June).Functional word use in an African Grey parrot. Paper presented at the annual meeting of the Animal Behavior Society, New Orleans, LA.
Pepperberg, I. M. (1981). Functional vocalizations by an African Grey parrot (Psittacus erithacus)Zeitschrift für Tierpsychologie,55, 139–160.
Pepperberg, I. M. (1983a). Cognition in the African Grey parrot: Preliminary evidence for auditory/vocal comprehension of the class concept.Animal Learning & Behavior,11, 179–185.
Pepperberg, I. M. (1983b, June).Interspecies communication: Innovative vocalizations of an African Grey parrot. Paper presented at the annual meeting of the Animal Behavior Society, Lewisburg, PA.
Pepperberg, I. M. (1985). Social modeling theory: A possible framework for understanding avian vocal learningAuk,102, 854–864.
Pepperberg, I. M. (1986). Acquisition of anomalous communicatory systems: Implications for studies on interspecies communication. In R. J. Schusterman, J. A. Thomas, & F. G. Wood (Eds.),Dolphin cognition and behavior: A comparative approach (pp. 289–302). Hillsdale, NJ: Erlbaum.
Pepperberg, I. M. (1987a). Evidence for conceptual quantitative abilities in the African Grey parrot: Labeling of cardinal setsEthology,75, 37–61.
Pepperberg, I. M. (1987b). Interspecies communication: A tool for assessing conceptual abilities in the African Grey parrot (Psittacus erithacus). In G. Greenberg & E. Tobach (Eds),Language, cognition and consciousness: Integrative levels (pp. 31–56). Hillsdale, NJ: Erlbaum.
Pepperberg, I. M. (in press). An interactive modeling technique for acquisition of communication skills: Separation of ‘labeling’ and ‘requesting’ in a psittacine subject.Applied Psycholinguistics.
Pepperberg, I. M., &Kozak, F. A. (1986). Object permanence in the African Grey parrot (Psittacus erithacus).Animal Learning & Behavior,14, 322–330.
Peterson, G. B. (1984). How expectancies guide behavior. In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds.),Animal cognition (pp. 135–148). Hillsdale, NJ: Erlbaum.
Premack, D. (1976).Intelligence in ape and man. Hillsdale, NJ: Erlbaum.
Premack, D. (1978). On the abstractness of human concepts: Why it would be difficult to talk to a pigeon. In S. H. Hulse, H. Fowler, & W. K. Honig (Eds.),Cognitive processes in animal behavior (pp. 423–451). Hillsdale NJ: Erlbaum.
Premack, D.. (1983). The codes of man and beasts.Behavioral & Brain Sciences,6, 125–167.
Putney, R. T. (1985). Do willful apes know what they are aiming at?Psychological Record,35, 49–62.
Reese, H. W. (1972). Acquired distinctiveness and equivalence of cues in young children.Journal of Experimental Child Psychology,13, 171–182.
Rumbaugh, D. M., &Pate, J. L. (1984). Primates’ learning by levels In G. Greenberg & E. Tobach (Eds.),Behavioral evolution and integrative levels (pp. 221–240). Hillsdale, NJ: Erlbaum.
Santiago, H. C., &Wright, A. A. (1984) Pigeon memory:Same/different concept learning, serial probe recognition acquisition, and probe delay effects on the serial-position function.Journal of Experimental Psychology: Animal Behavior Processes,10, 498–512.
Saunders, R., &Sailor, W. (1979) A comparison of the strategies of reinforcement in two-choice learning problems with severely retarded children.American Association for the Education of the Severely (Profoundly) Handicapped Review,4, 323–334.
Savage-Rumbaugh, E. S., Sevcik, R. A., Rumbaugh, D. M., &Rubert, E. (1985). The capacity of animals to acquire language: Do species differences have anything to say to us?Philosophical Transactions of the Royal Society, Series B,308, 177–185.
Shy, E., McGregor, P. K., &Krebs, J. (1986) Discrimination of song types by male great tits.Behavioural Processes,13, 1–12.
Thomas, R. K. (1980). Evolution of intelligence: An approach to its assessment.Brain, Behavior & Evolution,17, 454–472.
Todt, D. (1975). Social learning of vocal patterns and modes of their applications in Grey parrotsZeitschrift für Tierpsychologie,39, 178–188.
Wright, A. A., Santiago, H. C., &Sands, S. F. (1984). Monkey memory:Same/different concept learning, serial probe acquisition, and probe delay effects.Journal of Experimental Psychology Animal Learning Processes,10, 513–529.
Wright, A. A., Santiago, H. C., Urcuioli, P. J., &Sands, S. F. (1984) Monkey and pigeon acquisition of same/different concept using pictorial stimuli In M. L. Commons, R. J. Herrnstein, & A. R. Wagner (Eds.),Quantitative analysis of behavior (Vol. 4, pp 295–317) Cambridge, MA: Ballinger.
Zentall, T. R., Edwards, C. A., Moore, B. S., &Hogan, D. E. (1981). Identity: The basis for both matching and oddity learning in pigeons.Journal of Experimental Psychology: Animal Behavior Processes,7, 70–86.
Zentall, T. R., &Hogan, D. E. (1974). Abstract concept learning in the pigeon.Journal of Experimental Psychology,102, 393–398.
Zentall, T. R., Hogan, D. E., &Edwards, C. A. (1984). Cognitive factors in conditional learning by pigeons. In H. L. Roitblat, T. G. Bever, & H. S. Terrace (Eds),Animal cognition (pp. 389–405). Hillsdale, NJ: Erlbaum.
This research was supported by National Science Foundation Grant BNS 84-14483 and by the Harry Frank Guggenheim Foundation.
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Pepperberg, I.M. Acquisition of the same/different concept by an African Grey parrot (Psittacus erithacus): Learning with respect to categories of color, shape, and material. Animal Learning & Behavior 15, 423–432 (1987). https://doi.org/10.3758/BF03205051
- Transfer Test
- Conditional Discrimination
- Category Label
- Object Pair
- Grey Parrot