Summary: Human beings aren't the only creatures who make economic decisions. It turns out that monkeys do it, too. Scientists have observed our primate kin exchanging goods and services and adjusting prices. Ronald Noe, a professor of primate ethnology at the University of Strasbourg, says the vervet monkey of southern and eastern Africa uses grooming as a kind of currency. Vervets determine the value of food providers and divide their attention according to the law of supply and demand.
