A seabed predator known as deep sea arowana has developed a unique adaptation to compensate for its relatively small size.
With a length of just 15cm, Aristostomias scintillans have giant jaws, which are comparable to their body sizes and are more extensible to regular jaws.
This fish also has dozens of sharp canine teeth that are sharper than those found in piranhas. In order to keep prey in the dark, the arowana's teeth developed a transparent structure that essentially made their scary mouth invisible.
Image of deep sea dragon fish with transparent roasted set.
Researcher Marc Meyers, from the University of California, San Diego, said: "Most deep-sea animals have unique adaptations, but the fact that arowanas have transparent teeth confuses us. Because this feature is often found in larger species, we think the structure will be different and when we look at this, we find that particle-size nanocrystals are mounted on the teeth responsible for the calculation. This strange optical substance ".
The researchers collected specimens off California at a depth of about 500m below the surface. Using dedicated electron microscopes, they observed the morphology, nanostructures and composition of thin teeth and discovered that the arowana has an outer layer like enamel and an inner ivory layer like humans.
Nanocrystals scattered throughout these layers prevent any light from reflecting or scattering off the surface. Best of all, transparent teeth act as camouflage to hide their power in the dark. The harsh environment characterized by lack of ambient light, low temperature and high pressure has led to evolution to accommodate many deep-sea fish species.
"At large depths there are almost no light and small light emitted from fish, such as arowanas to attract prey. But the arowana's teeth have a very large proportion to its mouth," Meyers said . Like a monster in the movie about aliens'.
The teeth of some deep-sea fishes are somewhat transparent but have not been studied because it is difficult to obtain such specimens. Previously, researchers noted that their knowledge of structure and physical properties are not well understood, although they can make a difference in survivability.
Arowana is actually a top predator of the deep sea with a very unique hunting tool. Adaptation in jaw size allows it to eat one fish to half its size.