Of, relating to, or being the epoch of geologic time from about 2.6 million to 12,000 years ago, the older of the two epochs of the Quaternary Period. It is characterized by the alternate appearance and recession of northern glaciation, the appearance and worldwide spread of hominins, and the extinction of numerous land mammals, such as the mammoths, mastodons, and saber-toothed tigers. See Table at geologic time.
The Pleistocene Epoch.
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