The beady bits on the front of the Pacific barreleye fish in this picture released February 23, 2009, aren't eyes but smell organs.

The grayish, barrel-like eyes are beneath the green domes, which may filter light. In this picture the eyes are pointing upward--the better to see prey above in the darkness of the barreleye's deep-sea home.

Since the eyes are upright tubes, "it just looked like [they only] looked straight up," MBARI marine technician Kim Reisenbichler said. But by watching live fish from a remotely operated vehicle (ROV) and by bringing a barreleye to an aquarium for study, the scientists discovered that the eyes can pivot, like a birdwatcher pointing binoculars.

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