Paleolithic

The Paleolithic—also called the Old Stone Age—covers the vast majority of human prehistory, beginning with the earliest known stone tool use by hominins around 3.3 million years ago and ending with the close of the Pleistocene epoch roughly 11,700 years ago. Its name, coined by archaeologist John Lubbock in 1865, comes from Greek words meaning “old” and “stone.” During this period, people lived in small groups called bands, surviving by gathering plants, fishing, and hunting or scavenging wild animals. While stone tools were central—especially those made by knapping—wood, bone, leather, and vegetable fibers were also used, though organic materials rarely survive due to decay.

Around 50,000 years ago, the variety of artifacts increased sharply. In Africa, bone tools and the first known art appear in the archaeological record, and evidence of fishing emerges at sites like Blombos Cave in South Africa. Archaeologists sort artifacts from the last 50,000 years into many types, including projectile points, engraving tools, blades, and drilling or piercing implements. Over the Paleolithic, early members of the genus *Homo*, such as *Homo habilis* with their simple stone tools, gradually evolved into both anatomically and behaviorally modern humans by the Upper Paleolithic. By the Middle or Upper Paleolithic, people began creating the earliest artworks and engaging in spiritual practices like burial and ritual.

Climate during the Paleolithic fluctuated through glacial and interglacial periods, with warm and cool phases alternating. The Paleolithic overlaps with the Pleistocene epoch, which began 2.6 million years ago and ended 12,000 years ago—700,000 years after the Paleolithic started. During the preceding Pliocene, continents drifted to within about 70 km of their current positions. South America joined North America via the Isthmus of Panama, cutting off warm equatorial currents and lowering global temperatures. This connection also allowed fauna to cross between continents. Africa’s collision with Asia formed the Mediterranean Sea, closing off the Tethys Ocean. By the Pleistocene, continents were essentially in their modern positions, with tectonic plates moving at most 100 km since then.

Pliocene climates became cooler, drier, and more seasonal. Ice sheets grew on Antarctica, and an Arctic ice cap formed around 3 million years ago, signaled by shifts in oxygen isotopes and ice-rafted cobbles in ocean beds. Mid-latitude glaciation likely began before the Pliocene ended, and global cooling may have driven forest loss and the spread of grasslands. The Pleistocene featured repeated glacial cycles, with continental glaciers pushing to the 40th parallel in some areas. Four major glacial events and many minor ones occurred, separated by interglacials. Within a glacial, minor advances are called stadials, and the pauses between them are interstadials. Each glacial advance locked up vast water volumes in ice sheets 1,500–3,000 meters deep, dropping sea levels by 100 meters or more. During interglacials, coastlines often drowned, though some regions rose due to isostatic rebound.

Glaciation affected the entire globe. Antarctica remained ice-bound through the Pleistocene and Pliocene. The southern Andes were covered by the Patagonian ice cap, and glaciers existed in New Zealand and Tasmania. In Africa, glaciers on Mount Kenya, Mount Kilimanjaro, and the Ruwenzori Range were larger than today, and glaciers also appeared in the Ethiopian highlands and the Atlas Mountains. In the northern hemisphere, many glaciers merged into massive sheets: the Cordilleran Ice Sheet covered northwestern North America, and the Laurentide Ice Sheet spread over much of the continent.

Human migration accelerated late in the Paleolithic. By around 50,000 to 40,000 years ago, people first reached Australia. By about 45,000 years ago, humans lived at 61°N latitude in Europe. Japan was settled by roughly 30,000 years ago, and by 27,000 years ago, humans were present in Siberia above the Arctic Circle. By the end of the Upper Paleolithic, people had crossed Beringia and spread throughout the Americas.