21.   The pattern of his alleged crimes, Evans said, also could yield some clues about him.

22.   The seed was believed to be the oldest seed ever germinated, and scientists believed it might yield clues to the secret of aging.

23.   The size of the foal crop may not yield clues, either.

24.   They have spoken of small areas of the brain that appear to shrink, and psychological tests that yield subtle clues.

25.   Under microscopic and chemical analysis, the silica powder found with the anthrax might yield clues to its origin.

26.   What is more, her quiet life, and daily route from home to work, have yielded no clues.

27.   Because the mosaic was separated from the rest of the treasure, its discovery has yielded no clues to the whereabouts of the rest of the treasure.

28.   But repeated searches of the areas where the rebel said the four had been killed and buried yielded no clues.

29.   But the bone yielded no clues about how Levy died, they said.

30.   If the source of their protection can be identified, it could yield new clues for creating a vaccine against AIDS, scientists say.