Pleistocene
The geological epoch from about 2.58 million to 11,700 years ago, marked by repeated glaciations and the evolution and spread of humans.
Pleistocene glaciation: Repeated expansions and retreats of continental ice sheets during the Pleistocene. These cycles define the epoch’s most conspicuous environmental rhythm.
Geological time scale: A system for organizing Earth’s history into nested units of time. The Pleistocene is one named interval in this hierarchy.
Pleistocene megafauna: Large-bodied animals that lived during the Pleistocene, including mammoths, giant ground sloths, and saber-toothed cats. Their evolution, range shifts, and extinctions track changing Pleistocene environments.
Last glacial period: The most recent interval of widespread glaciation, lasting from about 115,000 to 11,700 years ago. Its cycles and retreat illustrate the late Pleistocene climate record.
Quaternary extinction event: The widespread loss of large terrestrial animals during the late Pleistocene and early Holocene. Its timing raises questions about climate change, human impacts, and their interaction.
Milankovitch cycles: Long-term variations in Earth’s orbit and axial orientation that alter the distribution of incoming sunlight. Their changing sunlight patterns paced many Pleistocene glacial cycles.
Quaternary: The geological period extending from about 2.58 million years ago to the present. The Pleistocene forms most of the Quaternary before the Holocene.
Human evolution: The evolutionary history of humans and their ancestors. Many major changes in human evolution occurred during the Pleistocene.
Eemian: The last interglacial period before the present, occurring roughly 129,000 to 116,000 years ago. Its warmth provides a comparison for climates between Pleistocene glaciations.
Overkill hypothesis: The hypothesis that human hunting caused or substantially accelerated late Pleistocene megafaunal extinctions. It offers a human-centered explanation contested alongside climate-based accounts.