These primitive tools were found on the eastern edge of the Arabian Peninsula, outside the range of Neanderthals. Researchers say humans may have left Africa earlier than previously thought, crossing what is now the bottom of the Red Sea. Science/AAAS hide caption

itoggle caption Science/AAAS

Gabrielle Giffords traveled by ambulance, private jet and helicopter from the University Medical Center in Tucson to a rehabilitation hospital in Houston on Friday. John Moore/Getty Images hide caption

itoggle caption John Moore/Getty Images