PLEISTOCENE

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Paleo-Geography

• Continents & oceans in current position
• Four major glacial advances (ice covered up to 30%
  of Earth's surface) follwed by interglacial warming
• Sea levels drop & rise as glaciers advance and melt
• Climate cold & dry world-wide
• Epoch ends in mass extinction; esp of megafauna

Life

• All modern plant & animal families present, land & sea
• Large mammals (megafauna) thrive (below)
• Tool-using pre-humans appear in Africa & spread throughout the Old World (below right)
• Neanderthal humans appear then disappear
• Modern humans (Homo sapiens) first appear
  

   Smilodon, the "Saber-Tooth   Cat" (left) flourished but
  went extinct at the end of
  the Pleistocene, along with   mammoths, mastodons,   glyptodons, ground sloths,   cave bears, & Neanderthals

        (Image: Peter Ashley)

Homo Erectus, "Upright Man"
(right). With larger brain capacity, greater tool use & the mastery of fire, they stopped being prey & started being predators. They walked out of Africa & spread throughout the Old World.

    (Image: Jay Matternes)

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