A definition of counting is adopted from R. Gelman and R. M. Gallistel (1978) and Piaget (1952) that allows for a comparison between animal and human counting behavior. The evidence, which ranges from early anecdotal reports to modern experimental analyses, suggests that a variety of infrahumans ranging from birds to primates can learn to count, although successful demonstrations are most likely to occur under relatively extreme experimental conditions when alternative predictors of food or safety are unavailable. Counting behavior appears to be a relatively unnatural response in infrahumans, and its acquisition may reflect the boundaries of the animal's associative abilities. (84 ref) (PsycINFO Database Record (c) 2012 APA, all rights reserved)