"...that light shall prevail over darkness..."
- motto of the American College of Veterinary Ophthalmologists

It’s been said our eyes are the window to the soul. Well, if that’s true, then every mammal on this planet’s got a soul, because when you look into the green, blue, deep brown, amber, black or grey eyes of us warm-blooded creatures, they tell stories words are hard to put to.

However, it has crossed my mind why is an octopus’s eye (five inches in diameter) is so much larger than my inch wide human eye? (I’m not an octopus, I know. Having no pigmentation in my own eyesâ€"due to my being an albino--I could sure use their vision, though, in just an eighth inch of what they can spare.)

Let me set this stage a bit. My interest in biology budded from sheer curiosity, to offer an explanationâ€"and self acceptance--for my own albinism and discovering how people died after they were dead biologically held a morbid fascination for me. It was only natural for me to equate that God designed every living critter across this Big Blue Marble, but to explain this to those having the faith that He did, in the symbiotic relationship with the how and why it was done, would win both scientific and God-fearing audiences under the simple logic and sense umbrella that God---er, the Intelligent Designerâ€"put us air and water-breathing creatures together in the first place,

Ironic I’m starting with eyes. It’s naturally what I’m attracted to (and I’m biased, my own are as violet as are Elizabeth Taylor’s). But I start there because my cat’s eyes glowed at me recently, it’s to illustrate this debut article for PSMâ€"and hey, once your eyes are openedâ€"you knew a pun was coming, roll with it!â€"in a very entertaining science lesson, other Intelligent Designer pieces to come from here won’t be as burdensome to swallow.

Whatever your eye color may be, enjoy it. Our eyes and animal’s eyes operate very much like a camera lens. When the hole in the lens gets smaller and the brim around it larger, less lens light is needed to develop the picture. In the back of that lens, much like the retina, the image is inverted. The iris is a muscle of the eye that constricts and expands based on how much light your eyes need to function in. That hole, incidentally, is a pupil. Darker irises (black, brown, light brown) have more pigment than lighter ones (green, blue, violet and grey) do and each iris radiates in a way that, like the finger and palm prints of the human hand, in individual patters from one person to another.

In front of the iris is a fluid that nourishes it, the lens and the cornea, is called aqueous humor. That’s a clear liquid that gives your eyes much needed nourishmentâ€"and can get slightly distressed when you rub your tired, dry or itchy eyes too much and your mom told you not to do that. Aqueous is a fancy way of saying “watery.â€?

Glaucoma is a buildup of that watery fluid in the forefront of the eye and happens when the normal ducts that drain and replace the AQ are ill angled to create blockage, clogs or are ill-formed. Cameras, though they have a lens, and a retina (the film) and invert those images onto the film to eventually develop a picture, is a very simplified way to explain the complex human and animal’s eye.

The lens itself, housed in a very thin, clear, cellophane-like wrapping called the lens capsule, is made of layers of fibers. Similar to an onion in its layers-like construction, the lens capsule is cut slightly to repair and discard cataract tissue from the lens of the eye. Behind that is gel like gooâ€"imagine someone watered down your favorite clear hair gel-- called the vitreous humorâ€"that aide human and animal’s eyes in two ways: to keep the retinasâ€"and tapetums, in an animal’s caseâ€"in place and to hold the eyeball’s smooth, almost spherical shape.

Only animals active at night have these tapetums, which underlie their light-retrieving retinas. It acts like a mirror when a cat, dog, horse, lion, hyena or cow look at an object at night and when they see something, their retinas register that something though the tapetum, bounce that light off the tapetum back to the retina where it’s registered again. Technically, they’re not seeing double but they get the image light enhanced, as it were, where humans don’t. That’s why animals have better night vision than do we bipeds. During the day, if you’ve ever seen an animal’s eyes narrow into the tiniest of slits for pupils, it’s due to that tapetum reflecting too much light back through their eyes. They don’t need the extra light their built in mirrors reflect in their eyes normal business hours.

Each animal, however, has different colored tapetumsâ€"and this is where our Intelligent Designer has to get credit, as opposed to mere chance and random chaos having a bigger say. Sheep’s eye tapetums are blue-green. Cows are amber-gold, as are cats and lions. Horses are reddish brown whereas dogs can range from gold to cobalt blueâ€"but only if you get a fresh animal’s eye. Pickled (preserved eyes soaking in embalming fluid) eyes tend to cloud the lenses brown, the muscles a dull gray, the vitreous humor is slightly yellowed and the tapetum turns a dull zinc green.

Your eyes get this reddish glow to them in pictures, car high beams or at night, why? Your retinas, which are a thin layer of light receptive cells joined to your optic nerve (which leads to the occipital lobe of the brain), are filled with tiny blood vessels called capillaries that pulse single blood cellsâ€"or corpusclesâ€"through those tiny pathways. In the retinas, along with those capillaries, comprise a huge network of blood vessels called Pukinji trees. These are bigger than capillaries, but small enough to feed and nourish the entire eye, optic nerve and the brain. Normal pigmented (colored) retinas may appear deep red, rust colored to almost brown; those which albinism, as like yours truly, the retinas are a deep orange from lack of pigment there. Incidentally, my Pukinji trees look like a mighty acorn tree branch, whereas yours may look like a few sticks readied for a campfire.

Enjoy the eyes. As my Granny used to say, “Take care of them well, you only get one pair.�

And, enjoy the One that made them. Just remember: those who are and were visually blindâ€"like Paul on the road to Damascusâ€"can usually see much more than you or I sometimes want to.

Another installment of “The Intelligent Designer Series� coming soon.

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