Archaeologists divide the pre-European American contact period of the region into three cultural phases. The Crane Flat phase lasted from 1000 BCE to 500 CE and is marked by hunting with the atl atl and the use of grinding stones.[4] The Tarmarack phase lasted from 500 until 1200, marked by a shift to using smaller rock points, indicating development and use of the bow and arrow.[4] The Mariposa phase lasted from 1200 until contact with European Americans.[4]