HOLEY COW A section of bone missing from the right side of a more than 5,000-year-old cow skull (front and back views, shown) resulted from a surgical procedure, researchers say.
F. Ramirez Rozzi
HOW SWEET Long before humans inhabited Polynesia, sweet potatoes may have been carried across the ocean from South America to the South Pacific islands by wind, water or maybe even birds.
ARABIAN POINTER A human finger fossil found in a Saudi Arabian desert dates to between 95,000 and 86,000 years ago, researchers say. This find, shown here from different angles, strengthens the view that ancient humans expanded into Asia via Arabia.