In the deep sea, dragons lure small fish near their jaws, with eyelids attached to beards with light. But the teeth of a predator in the size of a pencil do not glow in that light.
Instead, thanks to a nanoscale structure that reduces the amount of light transmitted by teeth, dragonfly teeth are transparent and difficult to recognize, the researchers reported at Matter on June 5.
According to Mark Myers, a scientist at the University of California in San Diego, a dagger disappears in the mouth of a dark animal, perhaps to help eels to surprise their prey. “They are mini monsters from the sea.
Dragonfly teeth resemble most animals: they contain an outer layer of enameled material that covers hard tissue called dentine. But nanostructures in both layers make this small cauldron stand out from other people’s pearls.
Microscopic electron transmission from the teeth of the dragonfly species (Aristostomias scintillans) shows small melting crystals of about 20 nanometers in enamel. In dentin, the researchers found a nanometer-sized protein collagen stem which was covered with hydroxylapatite minerals. If they are larger, such structures will spread light, but because of their small size, light will be transmitted with less bias, the scientists said. The tooth itself is also very thin, which also helps let light enter.
Dragon fish are not the only creatures with transparent teeth, but this is the first study to explore how these teeth interact with light, Myers said. The scientists caught the fish with a network of marine sanctuaries at a depth of about 500 meters.