Columban Simulation Project 2.0: Numerical Competence and Orthographic Processing in Pigeons and Primates

Abstract

Thirty years ago Burrhus Frederic Skinner and Robert Epstein began what is known as the Columban Simulation Project. With pigeons as their subjects, they simulated a series of studies that purportedly demonstrated insight, self-recognition, and symbolic communication in chimpanzees. In each case, with the appropriate training, they demonstrated that pigeons performed in a comparable manner to chimpanzees. When discussing these studies in the context of his Null Hypothesis, Macphail paid little attention to how the pigeons and chimpanzees solved the tasks and simply assumed that successful performance on the tasks reflected a similar underlying mechanism. Here, following a similar process to the original Columban Simulation Project, we go beyond this success testing and employ the signature testing approach to assess whether pigeons and primates employ a similar mechanism on tasks that tap numerical competence and orthographic processing. Consistent with the Null Hypothesis, pigeons and primates successfully passed novel transfer tests and, critically, displayed comparable cognitive signatures. While these findings demonstrate the absence of a qualitative difference, the time taken to train pigeons on these tasks revealed a clear quantitative difference.

Keywords: Null Hypothesis; comparative cognition; counting; numerical competence; orthographic processing; reading.

FIGURE 1

(A) Test performance of subjects. (B) Test performance of subjects as a function of the numerical distance between the test pair. (C) Response time of subjects as a function of the numerical distance between the test pair. (D) Test performance of subjects as a function of the numeric ratio between the test pair.

FIGURE 2

(A) Test performance of subjects. (B) The performance of subjects as a function of the bigram frequency of words. (C) The performance of subjects on non-words as a function of their similarity to words. (D) The performance of subjects on the transposed word test.