In an interesting discovery that has taken place recently, it has been found that while we as advanced species receive colour information via three colour receptors in our eyes, the mantis shrimp (Neogonodactylus oerstedii) have 12 such receptors.
This elucidated the fact that the complex eyes of mantis shrimp are equipped with optics that generates ultraviolet (UV) colour vision.
According to research reported in the Cell Press journal, six of such colour receptors can differentiate five discrete wavelengths of ultraviolet light. The mantis shrimps make use of specially tuned, UV-specific optical filters in their colour-detecting cells.
The optical filters of the mantis shrimps are found to be made of mycosporine-like amino acids (MAA) which are commonly called nature's sunscreens. These MAAs are usually used to protect an organism from UV rays that can damage DNA and is found in the skin or exoskeleton of marine organisms.
The mantis shrimp has incorporated these MAAs into powerful spectral tuning filters which make it possible to spot organisms that absorb UV light. Scientists have said that more research would be required to properly understand the complex visual perception of mantis shrimp and there is a possibility that UV detection could be used to visualize otherwise difficult to see prey on coral reefs.
Scientists have also found that the mantis shrimps view their underwater world in a whole new light, seeing ultraviolet colours far beyond and over the range of human vision.
The bulging eyes of these creatures contain built-in filters which are made from a biological sunscreen that is used by other marine animals to shield themselves against UV rays.
Why the mantis shrimp requires such a sophisticated visual system is still a mystery.
The creatures use their eyes to navigate and spot dangers of predators on the reefs where they live.