The All Seeing Eye

I have already demonstrated in this 'eye' series, that most insects have two compound eyes and three extra simple eyes, arranged in a triangle formation on top of the head. These simple eyes (ocelli) are used to sense light and dark and by triangulation, are an aid to direction memory. In addition, flying insects use the ocelli like a pilot's horizon indicator in an aircraft cockpit.

In my research for these eye blips, I came across a surprise, that many reptiles have a simple third eye positioned in the middle of the head, between the two normal simple eyes. This third eye, called the parietal or pineal eye, is photoreceptive and is thought to have something to do with circadian rhythm regulation, which we all know is about sleep patterns.

Nerves from this third eye connect to the pineal gland, deep within the brain, located between the two hemispheres. What surprised me was mammals used to have this third eye and many scientists believe that humans also had the third eye. We still have the pineal gland deep within our brains, but it is fed light information from our two eyes.

The parietal is part of the epithalamus which has two parts, the pineal gland and the parietal organ, the photoreceptive part. The scientists know all about the chemicals produced, the nerves and the blood supply, but amongst all the big words like: epiphysis, diencephalon, anterior evagination and placoderms, are words like: conjecture, possibly, theoretically and assertions. The only sure fact is that we still have a lot to learn.

The organ has been proven to be tied in to puberty, also it has been connected with ageing. There are strong arguments that connect the organ with near death experience and loose ties to the supernatural and sixth sense. As an engineer, I am not in to all this mumbo, but the presence of this organ kind of turns things around for me and offers a glimpse of an explanation. It seems that Indian culture of the all seeing third eye was not so far off the mark after all.

As for the frog, well they always seem to be able to sense when I am approaching with my third eye!

Dave