Anglerfish

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For nearly a half-hour, scientists filmed the female anglerfish as she tumbled gently along with the ocean current at a depth 2,600 feet. The footage features her parasitic mate, a male one-tenth her size, clutched to her belly... The pair was observed off the steep southern slope of São Jorge Island, located in the central Azorean archipelago of Portugal...

"One can't help but think these fin-rays form a network of sensory antennae, a kind of sphere of tactility around the fish -- akin to cat whiskers -- that functions to monitor the close presence of predators or prey," said Ted Pietsch, a professor of aquatic and fishery sciences at the University of Washington.