The barreleye’s eyes point upward—then rotate forward to feed.
MBARI’s remotely operated vehicle recorded this fish above Monterey Canyon.
Its green, tubular eyes sit beneath a clear, fluid-filled shield.
Researchers link that posture to feeding, but the footage does not show every prey decision.
Earlier specimens often lost the shield when nets damaged the fragile tissue.
The living footage clarified why older specimens looked different: the shield was intact.
So the eyes really pivot for feeding; exactly how prey tracking works remains unknown.