After millions of years of evolution, scientists have discovered a third eye buried in the center of the human head and claim it continues to serve an important role.
This ancient organ was dubbed the composite ancestral median eye by researchers from the UK and Sweden. They now think that the species from which humans descended relied on this eye after losing their two side eyes some 500 million years ago.
Their research indicates that these prehistoric non-vertebrate species—that is, animals without backbones—burrowed underground and lost the ability to see with their regular eyes, relying instead on this central eye to detect light.
The remains of the third eye are still present in human skulls today. Although it can no longer detect light, it still uses the information it gets from our eyes about light and darkness to help control when individuals go to sleep.
In particular, the hormone melatonin, which alerts the body to the night and the need for slumber, is produced by the third eye.
This aids in the synchronization of circadian rhythms, a 24-hour cycle that affects the body’s various physiological functions both during the day and at night and encourages sleepiness.
This involves regulating the immune system, reproductive system, and, according to some scientists, even our mood and body temperature regulation.
The pineal gland is the current name for this organ. It is composed of unique cells called pinealocytes that emit melatonin, even though it is no longer a true eye.
The evolutionary history of the human “third eye,” an ancient organ still present in the human skull that non-vertebrate predecessors depended on, has been revealed by scientists (Stock Image).
According to scientists, humans descended from an ancestor creature that lost its typical side eyes and gained a central eye in the middle of its skull.
Determining how the human eye and retina changed over hundreds of millions of years was the aim of the new study, which was published in Current Biology.
The earliest human predecessors had both side eyes and a center light-sensing organ in their heads, according to research conducted by neurologist Professor Thomas Baden of the University of Sussex.
Some of these early relatives lost their side eyes when they started burrowing and filter-feeding half a billion years ago. As a result, they mostly relied on this central structure to detect direction and determine whether it was day or night on the surface.
The essential nerves known as retinas that we have in our eyes today are thought to have developed from pieces of the third eye that traveled to the sides of the head much later.
“The need to know what time of day it is, or where is up and down if you’re in deep water,” Baden said to BBC Science Focus. That remains. humans therefore hypothesize that humans lost the original side eyes at that point, but we retained the original median eye because of its usefulness.
“So, if that makes sense, the retina comes before the eye,” the researcher continued.
Neither new experiments nor scans were conducted by the multinational team. Rather, they carefully examined a number of previous research and genetic data from animals like fish and lampreys to determine whether this eye is still useful in human-related species.
By demonstrating that human retinas and the pineal gland originated from the same ancient structure rather than evolving independently, the findings have altered scientists’ understanding of this enigmatic eye.
The pineal gland’s cells release melatonin to control sleep, and humans still have traces of this third eye inside their skulls (Stock Image).
The tuatara, a reptile from New Zealand, is one of the few animals that still possesses a visible third eye. This organ has a lens and retina, exactly like regular eyes.
Its primary function is to detect changes in light, particularly overhead light from the sky, rather than to perceive fine images. This aids the tuatara in controlling its circadian rhythms and daily actions, such as knowing when to hide or enjoy the sun.
There has long been a concept that the human “third eye” is connected to supernatural skills like intuition, inner vision, and psychic awareness, even though there is no reliable scientific evidence to support this theory.
The third eye is associated with the “Ajna chakra,” an energy point in the human body, according to Hindu and yogic traditions.
According to ancient writings on yoga, this chakra’s awakening can grant clairvoyance, telepathy, and spiritual insight.
