Numerity of a socially housed hamadryas baboon (Papio hamadryas) and a socially housed squirrel monkey (Saimiri sciureus)

To extend a study conducted by E. M. Brannon and H. S. Terrace (1998, 2000), the authors trained 1 hamadryas baboon (Papio hamadryas) and 1 squirrel monkey (Saimiri sciureus) to respond to stimuli representing the numerosities 1–4 in ascending order. When tested with novel stimuli of the same numerosities, both subjects’ performance appeared to be […]