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Lake Boku at the Ounianga oasis in remote northeastern Chad, one of the few remaining bodies of water in the almost rainless Sahara. Still sustained by fossil groundwater dating from the humid past, it is doomed because of encroaching dunes.

The Roots of Morality
Neurobiologists, philosophers, psychologists, and legal scholars are probing the nature of human morality using a variety of experimental techniques and moral challenges.

To Touch the Water of Mars and Search for Life's Abode
The Phoenix lander will soon arrive at Mars to perform the first analyses of martian water and to probe the rocky polar soil as a habitat for life; it has been a struggle.

Talk Nerdy to Me
A surprise hit, the new TV comedy The Big Bang Theory plumbs science for laughs, thanks to aid from physicist David Saltzberg and friend.

Into the Wild: Reintroduced Animals Face Daunting Odds
Researchers in the emerging field of wildlife reintroduction battle hawks, habitat loss, and poachers to give animals a second chance.

Climate-Driven Ecosystem Succession in the Sahara: The Past 6000 Years
A climate record from lake sediments in Chad shows that the Sahara changed gradually from a tropical ecosystem to a desert, not abruptly as implied by Atlantic dust layers.

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