Numerical competence in a chimpanzee (Pan troglodytes).

@article{Boysen1989NumericalCI,
  title={Numerical competence in a chimpanzee (Pan troglodytes).},
  author={Sarah T. Boysen and Gary G. Berntson},
  journal={Journal of comparative psychology},
  year={1989},
  volume={103 1},
  pages={
          23-31
        }
}
A chimpanzee (Pan troglodytes), trained to count foods and objects by using Arabic numbers, demonstrated the ability to sum arrays of 0-4 food items placed in 2 of 3 possible sites. To address representational use of numbers, we next baited sites with Arabic numbers as stimuli. In both cases performance was significantly above chance from the first sessions, which suggests that without explicit training in combining arrays, the animal was able to select the correct arithmetic sum for arrays of… 

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References

SHOWING 1-10 OF 41 REFERENCES

A vocabulary test for chimpanzees (Pan troglodytes).

Analysis of errors showed that two aspects of the signs, gestural form and conceptual category, governed the distribution of errors.

Summation in the chimpanzee (Pan troglodytes).

It was concluded that without any known ability to count, these chimpanzees used some process of summation to combine spatially separated quantities.

Simian scribbles: a reappraisal of drawing in the chimpanzee (Pan troglodytes).

The present results agree with earlier findings that chimpanzees will engage in drawing activities without training or reinforcement, and this behavior may reflect their intrinsic interest in exploratory and manipulative play.

Primative mathematical concepts in the chimpanzee: proportionality and numerosity

In the experiments reported here, an adult chimpanzee and four juveniles were tested for their knowledge of ‘proportion’ and ‘number’ with conceptual match-to-sample tasks and the results reveal the presence of simple 'proportion' and 'number' concepts in a nonhuman primate.

Cardiac correlates of individual recognition in the chimpanzee (Pan troglodytes).

Results indicate that the chimpanzee is able to recognize individual humans from novel photographic representations and that heart rate can provide an objective measure of such recognition.

Conspecific recognition in the chimpanzee (Pan troglodytes): cardiac responses to significant others.

The chimpanzee is able to recognize photographs of individual conspecifics and that heart-rate change can reflect the nature of established social relationships between chimpanzees.

Perception of numerical invariance in neonates.

It is argued that the ability to abstract numerical invariance from small-set visual arrays and may be evidence for complex information processing during the first week of life.

Relative numerousness judgments by squirrel monkeys

With nonnumerousness dimensions (e.g., pattern, area) controlled, three cards with two to seven black-filled circles were presented on each trial. If the center of three conditional cue lights was

Ape Language: From Conditioned Response to Symbol

In this pioneering study, the author traces the acquisition of symbols by two chimpanzees, from their simplest beginnings to their use as representational statements about future actions. The