A research team led by neurobiologist Margaret Livingstone trained three rhesus macaques to identify symbols representing the numbers zero to 25. To eliminate the possibility of rote learning, the team had the monkeys learn an entirely different set of symbols representing the numbers zero to 25. The monkeys were able to reapply their previous knowledge to the new set and continue performing basic mathematics. The image above shows one of the monkeys preparing to choose the four and five combination on the panel.