Prehistory spans from the origin of humans until the development of writing around 3500 BC. It is divided into three main periods: Palaeolithic, Neolithic, and the Age of Metals. The Palaeolithic period saw several human species evolve over millions of years, including Australopithecus which walked upright 4.5 million years ago, Homo habilis who made basic tools 2.3 million years ago, and Homo erectus who was the first to spread out of Africa 1.9 million years ago and use complex tools and control fire. Neanderthals appeared 300,000 years ago in Europe during the Ice Age and made complex flint tools, while modern humans emerged in East Africa around 200