Desert menu

Natural History, Dec, 2008 by Robert Anderson

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LOOK AT AFRICA FROM SPACE, and you'll notice a belt of dark green across the continent's midsection. A friend studying a poster of Earth once asked me what caused that "shadow." It's vegetation, of course, and what makes it stand out is the contrast with the continent's arid regions, most notably the Sahara Desert. Scientists at the University of Kiel, Germany, however, have shown that three times within the past 120,000 years, the Sahara region was covered in grassland, lakes, and ponds (see "The Green Sahara, A Desert in Bloom" at www.uni-kiel.de/aktuell/pm/2008/2008-088-klima-sahara-e.shtml). For my guide to Web sites exploring the Sahara's climate and ancient history, please visit the magazine online (www.naturalhistorymag.com).

ROBERT ANDERSON is a freelance science writer who lives in Los Angeles.