An important clue, he said, is found in the faces of apes, which draw up their mouths as well.
Whether dark energy has retained its value throughout the history of the universe is an important clue to its nature.
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.
Spending $1 billion on patents offers an important clue to what matters most to Page: innovation.
