This search for the missing link is the holy grail of evolutionists, all I got out of this article is the fact that different creatures have different eye structures, some more complex than others.
A couple examples;
Most eyes have optical systems that are based on refraction by a lens or a cornea. However, there are two eye types that form images using mirrors. These are concave mirror eyes, similar in principle to a Newtonian telescope, and reflecting superposition compound eyes, where the mirrors are arranged radially in a square array. The concave mirrors are found in scallops (Pecten), where they allow the eye to see moving objects, and in a modified form in a few deep-sea crustaceans. The reflecting superposition eyes are confined to the long-bodied decapod crustaceans - the shrimps, prawns, crayfish and lobsters. Recently this second mechanism has found a number of uses in x-ray optics.
Fish eyes are different from our own. Their lenses are perfectly spherical, which enables them to see underwater because it has a higher refractive index to help them focus. They focus by moving the lens in and out instead of stretching it like we do. They cannot dilate or contract their pupils because the lens bulges through the iris. As the depth at which fish are found increases, the resident fish's eye sizes increase in order to gather the dimmer light. This process continues until the end of the photic zone, where eye size drops off as their is no light to see with. Nocturnal fish tend to have larger eyes then diurnal fish. Just look at a squirrelfish, and you will see this to be so. Some fish have a special eye structure known as the Tapetum lucidum, which amplifies the incoming light. It is a layer of guanine crystals which glow at night. Photons which pass the retina get bounced back to be detected again. If the photons are still not absorbed, they are reflected back out of the eye. On a night dive, you may see these reflections as you shine your light around!
And this is just for fish!
Peace,
Joe
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Topic: Missing link in the evolution of the eye? (Read 6331 times)