Title: desert  | National Geographic Society
Headings: desert
desert
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Content: Few organisms can withstand the freezing, dry climate of Antarctica. Changing Deserts
The regions that are deserts today were not always so dry. Between 8000 and 3000 BCE, for example, the Sahara had a much milder, moister climate. Climatologists identify this period as the “ Green Sahara .” Archaeological evidence of past settlements is abundant in the middle of what are arid, unproductive areas of the Sahara today. This evidence includes rock paintings, grave s, and tools. Fossil s and artifact s show that lime and olive trees, oaks, and oleander s once bloomed in the Sahara. Elephants, gazelles, rhinos, giraffes, and people used stream-fed pools and lakes. There were three or four other moist periods in the Sahara. Similar lush conditions existed as recently as 25,000 years ago.