Have you ever heard of the box jellyfish? They are also called Tripedalia cystophora. They live in the swampy roots of the Caribbean mangrove trees. These interesting creatures navigate their murky habitat with eyes permanently fixed on the world above their own. So, why do they constantly keep their eyes to the sky?

The box jellyfish in the lagoons of Puerto Rico have 24 eyes - 4 sets with 6 eyes in each set. Two out of the 6 are called the upper and lower lens eyes. The upper lens eye sits atop each clustered set, looking up. The jellyfish feed on small crustaceans called copepods. The copepods are attracted to the patches of light that enter between the dense shades of the mangrove canopy. The box jellyfish keep their eyes on the canopy at all times to remain close to their home and feeding ground. Otherwise, they risk swimming into open water, where they would starve.

How good are their eyes then? According to the research done by Anders Garm from the University of Copenhagen, the upper lens eyes can spot the canopy from 8 meters away and see the world refracted through the water, compressed at an angle of about 95 degrees. Considering that jellyfish have no complex, centralized brain, it is remarkable. The lower lens eye and the other 4 in each set are used to avoid bumping into obstacles, determine light intensity, and other less-advanced functions.

All these eyes, therefore, seem to have specific, specialized tasks. Dr. Garm suggests that this was the way the eyes worked when they first evolved before a single pair of eyes were able to take on all the required tasks. What if we have many eyes like the box jellyfish? Can you imagine having more than two eyes?