mcgrew writes "New Scientist is reporting that "non-human primates really can understand the meaning of numerals." The small study of two rhesus monkeys reveals that cells in their brains respond selectively to specific number values — regardless of whether the amount is represented by dots on a screen or an Arabic numeral. For example, a given brain cell in the monkey will respond to the number three, but not the number one. The results suggest that individual cells in human brains might also have a fine-tuned preference for specific numerical values." The report itself is online at PLoS Biology, Semantic Associations between Signs and Numerical Categories in the Prefrontal Cortex."