Paleolithic

The Paleolithic, also called the Old Stone Age, covers nearly all of human prehistory when it comes to technology. It began with the first known stone tools made by hominins around 3.3 million years ago and lasted until the end of the Pleistocene, about 11,650 years ago. In Europe, it came before the Mesolithic, though the exact transition date varied by region by thousands of years. People lived in small groups called bands, surviving by gathering plants, fishing, and hunting or scavenging wild animals. The era is defined by knapped stone tools, but wood and bone were also used, along with organic materials like leather and vegetable fibers—though these rarely survived due to decay.

Around 50,000 years ago, artifacts became much more diverse. In Africa, bone tools and the earliest art appeared, and the first evidence of fishing emerged, such as at Blombos Cave in South Africa. Archaeologists sort artifacts from the last 50,000 years into categories like projectile points, engraving tools, blades, and drilling or piercing tools. Humans evolved from early Homo species, like Homo habilis with simple stone tools, into both anatomically and behaviorally modern humans by the Upper Paleolithic. By the Middle or Upper Paleolithic, people created the earliest art and engaged in spiritual practices, including burials and rituals. The climate swung between glacial and interglacial periods, with warm and cold cycles.

By about 50,000 to 40,000 years ago, humans first reached Australia. Around 45,000 years ago, they lived at 61°N latitude in Europe. By 30,000 years ago, they had reached Japan, and by 27,000 years ago, they were in Siberia above the Arctic Circle. By the end of the Upper Paleolithic, they had crossed Beringia and spread throughout the Americas.

The term "Paleolithic" was coined by archaeologist John Lubbock in 1865, from Greek *palaios* (old) and *lithos* (stone), meaning "Old Stone Age."

The Paleolithic overlaps with the Pleistocene epoch, which began 2.6 million years ago—700,000 years after the Paleolithic started—and both ended 12,000 years ago. The Pleistocene saw major geographic and climatic changes. During the preceding Pliocene, continents drifted to within about 70 km of their current positions, from as far as 250 km away. South America connected to North America via the Isthmus of Panama, nearly ending its unique marsupial fauna. This isthmus cut off warm equatorial currents, lowering Atlantic Ocean temperatures as cold Arctic and Antarctic waters were isolated. Most of Central America formed during the Pliocene, linking the continents and allowing fauna to migrate. Africa’s collision with Asia created the Mediterranean, cutting off the Tethys Ocean. By the Pleistocene, continents were near their modern positions, with tectonic plates moving at most 100 km apart since then.

Pliocene climates became cooler, drier, and more seasonal, like today. Ice sheets grew on Antarctica. An Arctic ice cap formed around 3 million years ago, shown by a shift in oxygen isotopes and ice-rafted cobbles in the North Atlantic and Pacific. Mid-latitude glaciation likely began before the Pliocene ended. Global cooling may have reduced forests and spread grasslands and savannas. The Pleistocene featured repeated glacial cycles, with continental glaciers pushing to the 40th parallel in places. Four major glacial events and many minor ones occurred. A glacial is a major advance, separated by interglacials; within a glacial, minor advances are stadials, with interstadials in between. Each glacial advance locked up huge water volumes in ice sheets 1,500–3,000 meters deep, dropping sea levels by 100 meters or more globally. During interglacials, coastlines often drowned, though isostatic rebound lifted some regions.

Glaciation was global. Antarctica remained ice-bound through the Pleistocene and Pliocene. The Andes were covered by the Patagonian ice cap in the south. Glaciers existed in New Zealand and Tasmania. Decaying glaciers on Mount Kenya, Mount Kilimanjaro, and the Ruwenzori Range in Africa were larger, and glaciers also appeared in Ethiopia and the Atlas Mountains. In the northern hemisphere, many glaciers merged. The Cordilleran Ice Sheet covered northwestern North America, and the Laurentide Ice Sheet covered much of the continent.