a rightly timed pause

A realistic understanding of the function of the components of the eye began around the 17th century, after the gross anatomy of the eye had been firmly established. It was realized in the 17th century that the retina, not the cornea as was previously thought, was responsible for the detection of light. Johannes Kepler of Germany and Renee Descartes of France, both prominent physicists of their time, made many advances in understanding vision. Much of their work applied the physical concepts of light rays and geometric optics to the vision process. Kepler first proposed that the lens of the eye focuses images onto the retina. A few decades later Descartes demonstrated that Kepler was correct. In a landmark experiment, Descartes surgically removed an eye from an ox and scraped the back of the eye to make it transparent. He then placed the eye on a window ledge as if the ox were looking out of the window. He looked at the back of the eye he and saw an inverted image of the scenery outside! Descartes correctly postulated that the image was inverted as a result of being focused onto the retina by the eye’s lens.

But why?

Perhaps it’s because light entering from a low angle strikes high in the retina and vice versa. If images weren’t inverted on the retina by the lens, then the field of vision in both the up and down directions would be constrained. Think it through

And now consider the evolutionary advantage of having a broader 3-dimensional perspective.

Geometry informs genetic ‘design’ …

Just a thought.