Prehistoric technology Ground and polished stone tools continued to be created and used during the Neolithic period. Numeric record keeping evolved from a system of counting using small clay tokens that began in Sumer about 8000 BC. The Stone Age developed into the Bronze Age after the Neolithic Revolution. The Neolithic Revolution involved radical changes in agricultural technology which included development of agriculture, animal domestication, and the adoption of permanent settlements. The Bronze Age is characterised by metal smelting of copper and its alloy bronze, an alloy of tin and copper, to create implements and weapons. Polished stone tools continued to be
Neolithic to retrieve a more precise date for the site. In Mesoamerica, a similar set of events (i.e., crop domestication and sedentary lifestyles) occurred by around 4500 BC, but possibly as early as 11,000–10,000 BC. These cultures are usually not referred to as belonging to the Neolithic; in America different terms are used such as Formative stage instead of mid-late Neolithic, Archaic Era instead of Early Neolithic and Paleo-Indian for the preceding period. The Formative stage is equivalent to the Neolithic Revolution period in Europe, Asia, and Africa. In the southwestern United States it occurred from 500 to 1200 AD when