Primal Eye

The PRIMAL EYE

First to clarify some terminology. The terms Pineal/ Parietal/ Old/ Median /Primal or Primary are interchangeable alternatives when describing the ancient ‘eye’ or ‘sense-organ.’ "Third eye" is sometimes used although this is a misnomer since the pineal-eye pre-dates our two ‘lateral eyes.' The intracranial pineal body (glandular structure) can also be called the epipyphis or epiphyseal complex when it includes the median eye. I shall use the notation E-2 indicating the presence of both pineal body and median eye ... the most primitive condition and E-1 when just the pineal body (or impression in fossil skulls) remains. E-0 indicates a complete absence of any pineal apparatus.

By consciousness I refer to the ability to have any mental representations whatsoever. Other words (sentience, attentionality, etc.) might equally suffice. Analytic academic philosophy is concerned with words, but MVT draws from and examines the PHENOMENA found in nature. A good natural theory always beats a non-natural one.

It is important to establish some scientific ground. The a slight foramen (skull opening) in which once house the median eye is a common feature of vertebrate skull morphology. Most living vertebrates belong to type E-1. An E-O condition exists among certain dinosaurs who appear to have lost their entire epiphyseal complex; along with modern members of crocodilia.

The more primitive E-2 categories, retaining median eyes, are relatively uncommon among living animals. Experiments have been made on the median eyes of certain families of lizards (Gundy et al, 1975), and importantly, by Dendy on the Sphenodon (1899, 1911) before these creatures became highly protected and intrusive experiments banned. Interestingly, the eye atrophies during the lifetime of the sphenodon, and older animals lose sensitivity of the organ. Lampreys, a primitive, parasitic fish, and the Stirnogen, observed in three families of anuran amphibians, apparently complete the distribution of E-2 median eye-like photoreceptors among modern vertebrates.

The refinement of sensory systems and accompanying perception of environmental stimuli has been a major theme in over 400m years of vertebrate evolution. The later and more adapted lateral eyes usurped median apparatus as the sole supplier of light-information and seemingly made the old eye redundant because of their greater optical sophistication, muscular control, and stereoscopic advantages.