It's no secret that other animals use tools; dolphins and otters have been seen to use rocks to break mollusc's shells, and crows have been recorded using strands of grass to fish tasty snack-ants from their colonies; what need is there for primate archaeology? Just using tools doesn't mean you've entered the stone age, right!?
The chimpanzees of West Africa use a different shaped stone for digging up a tubers than they would for smashing a nut. They give different tools different tasks and they pass this info onto their offspring. This means they've entered the Stone Age.
The chimps of the Ivory Coast, the bearded capuchins of Brazil and the long-tailed macaques of Thailand are cousins of ours that evolutionarily separated from humans between 25-35 million years ago. They have each, independently, met our criteria for entering the Stone Age.
Humans advanced into the Stone Age 3.3 million years ago. West African simian stone tools have been dated at around 4300 years old. 4300 years ago, our species were building the pyramids.
I can't wait to see the Monkey Sphinx.
Viva la revolución del chimpancé.