Prehistory is the period before written history. The early human migrations in the Lower Paleolithic saw "Homo erectus" spread across Eurasia 1.8 million years ago. The controlled use of fire first occurred 800,000 years ago in the Middle Paleolithic. 250,000 years ago, "Homo sapiens" (modern humans) emerged in Africa. 60–70,000 years ago, Homo sapiens migrated out of Africa along a coastal route to South and Southeast Asia and reached Australia. 50,000 years ago, modern humans spread from Asia to the Near East. Europe was first reached by modern humans 40,000 years ago. Humans migrated to the Americas about 15,000 years ago in the Upper Paleolithic.