Absorbing 99.95 percent of all photons, this blacker-than-black exterior creates a cloak of invisibility against the ocean's dim backdrop. Even under a harsh spotlight, these creatures appear as mere silhouettes. Incidentally, this is what initially piqued Karen Osborn's interest. As a research zoologist at the Smithsonian's National Museum of Natural History, she grew frustrated trying to photograph a striking black fish that had been pulled from the deep sea.