An important clue, he said, is found in the faces of apes, which draw up their mouths as well.
U.S. geologists say they may have found the answer — or at least an important clue — in a bone-dry desert in Egypt, of all places.
Whether dark energy has retained its value throughout the history of the universe is an important clue to its nature.
Spending $1 billion on patents offers an important clue to what matters most to Page: innovation.