Use of numbers by a chimpanzee

  title={Use of numbers by a chimpanzee},
  author={Tetsuro Matsuzawa},
Recent studies have examined linguistic abilities in apes1–6. However, although human mathematical abilities seem to be derived from the same foundation as those in language, we have little evidence for mathematical abilities in apes (but for exceptions see refs 7–10). In the present study, a 5-yr-old female chimpanzee (Pan troglodytes), ‘Ai’, was trained to use Arabic numerals to name the number of items in a display. Ai mastered numerical naming from one to six and was able to name the number… 
Symbolic representation of number in chimpanzees
  • T. Matsuzawa
  • Biology, Psychology
    Current Opinion in Neurobiology
  • 2009
Use of numerical symbols by the chimpanzee (Pan troglodytes): Cardinals, ordinals, and the introduction of zero
An adult female chimpanzee with previous training in the use of Arabic numerals 1–9 was introduced to the meaning of "zero" in the context of three different numerical tasks, suggesting that the level of abstraction characteristic of human numerical ability was not attained in the chimpanzee.
Spontaneous Spatial Mapping of Learned Sequence in Chimpanzees: Evidence for a SNARC-Like Effect
The Chimpanzees' performance was systematically influenced by the spatial arrangement of the stimuli; specifically, they responded quicker when 1 was on the left and 9 on the right compared to the other way around, which suggests that chimpanzees, like humans, spontaneously map a learned sequence onto space.
Indicating acts during counting by a chimpanzee (Pan troglodytes).
A chimpanzee experienced in counting arrays of 0-7 items and trained for comprehension of number symbols, spontaneously displayed a variety of indicating acts during counting, suggesting that the use of indicates by this animal may have functional significance and serves as an organizing schema, comparable to similar behaviors observed in children in the early stages of learning to count.
Enumeration of briefly presented items by the chimpanzee (Pan troglodytes) and humans (Homo sapiens)
Detailed analyses of the pattern of response times for the chimpanzee and of looking-back behavior during the task suggests that the enumeration process underlying the subject’s performance was not counting but estimation.
Use of Number by Fish
Mosquitofish can learn to discriminate small quantities, even when non-numerical indicators of quantity are unavailable, hence providing the first evidence that fish, like primates, can use numbers.
Long-term retention of the differential values of Arabic numerals by chimpanzees (Pan troglodytes)
  • M. Beran
  • Psychology, Biology
    Animal Cognition
  • 2003
Data are provided to provide an experimental demonstration of long-term retention of the differential values of Arabic numerals by chimpanzees.
Categorical replies to categorical questions by cross-fostered chimpanzees.
Results reported here add depth to the patterns demonstrated in earlier studies, and demonstrate that even when their reply was incorrect, these chimpanzees usually replied with a sign from the category specified by the question.
"Constructive" enumeration by chimpanzees (Pan troglodytes) on a computerized task
Chimpanzee counting in this type of experimental task may be a process that represents magnitudes with scalar variability in that the memory for magnitudes associated with each numeral is imperfect and the variability of responses increases as a function of the numeral's value.


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.
Can an ape create a sentence?
More than 19,000 multisign utterances of an infant chimpanzee (Nim) were analyzed for syntactic and semantic regularities, showing similar non-human patterns of discourse.
Acquisition and Testing of Gestural Signs in Four Young Chimpanzees
Some signs were consistently easier to acquire than others, and individual differences between the four chimpanzees were found in the acquisition rates and tests.
Intelligence In Ape And Man
Teaching sign language to a chimpanzee.
The protein encoded by Nup160 directly interacts with that of another hybrid lethality gene, Nup96, indicating that at least two lethal hybrid incompatibility genes have evolved as byproducts of divergent coevolution among interacting components of the Drosophila nuclear pore complex.