RetGen

The pineal gland?which regulates the cycles of sleep and waking?appears to have evolved as an indirect way to improve vision, by keeping toxic compounds away from the eye, according to a new theory by a researcher at the National Institute of Child Health and Human Development at the National Institutes of Health.

The theory has implications for understanding macular degeneration, a condition causing vision loss in people age 60 and older.
'Pineal Gland Evolved To Improve Vision, According To Theory By NICHD Scientist,' US National Institutes of Health media release, 12 August 2004.