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Wild Winds Made Gorgeous Mars Gorges
: The ice cap of Mars's north pole was sculpted over millions of years.
Microbes Are the Key to a Happy Gut
: Each person's unique ecosystem of gut microbes plays a vital role in good health.
Sinkhole Eats Guatemala City
: Well, it didn't devour the entire city, but it did take down a clothing factory.
CIA Doctors Did Forbidden Research
: A report states that doctors went too far with prisoners after the 9/11 attacks.
Astronomers Catch an Asteroid Smashup
: An X-shaped tail provides direct evidence of a space collision.
Haitian Quake Signals Future Shocks
: Is the Caribbean in for more serious shakes?
Our Jumbled Ancestor
(pictured): With a braincase and limb bones that don't look like they're from the same species, this fossil poses an evolutionary riddle.
Science Saves the Chilean Miners
: The dramatic rescue was a triumph of engineering and psychology.
Sleep Switch Found in the Brain
: The chemical trigger that lets us nod off may not work on the whole brain at once.
Autism: One Label, Many Diseases
. A study of more than 1,000 autistic children reveals daunting diversity in their genetic variations.