A Marvel of Adaptation: Ophthalmologists Explain How The Human Eye Developed

Have you ever wondered how it is that you’re able to see both in the dark and light, can discern relative distance, or focus on objects both near and far? It has everything to do with the design of the human eye, a unique and amazing product of evolutionary development. But the question of how this organ actually came into being stumped even the first proponent of evolution, Charles Darwin. Over time, however, scientists have been able to explain the development of this super sensitive and specialized sense organ.

As this Ted-Ed video explains, the human eye developed through a series of selective adaptations, and this evolutionary history can be seen in the way our vision works.

As it explains, the history of the eye can be traced to over 500 million years ago, when single-celled organisms developed a light spot that was sensitive to the presence or absence of light. This apparatus eventually became more specialized as it became a cup-shaped apparatus, which allows for detection of the origin of light, an adaptation that allowed ancient worm-like organisms to seek out darker areas in which they could hide from predators. Further adaptive developments, such as the pin-hole of the nautilus’s eye, allowed for better resolution and more detail. This further increased resolution and cut down on distortion because only a small amount of light is let in for analysis by the brain.

But the true key to understanding the functionality and development of the human eye has to do with the development of the lens. Because it prevents outside air or water from entering, the inside of the eyeball eventually filled with fluid, allowing for even better acuity and light sensitivity. As evolution progressed, our mammalian ancestors also developed adjustable lenses and the iris—the colored ring around your pupil—that can regulate the amount of light that gets in (allowing for vision in all kinds of light conditions). These developments were matched by brain adaptations, allowing for the kind of processing and visual acuity that we experience today.

Since the eyes are a marvel of over 500 million years of selective adaptation, you owe it to yourself to take good care of them. Hawaii Vision Clinic Inc., is the premier ophthalmology practice on Oahu. Come in for your glasses or contact lenses examinations, as well as a wide variety of other treatments.

The folks at Hawaii Vision Clinic have a reverence for the amazing capability of the eye, and they want to keep your eyes healthy and seeing well. Learn more about this unique, locally owned and operated practice by visiting them online, and to make an appointment, call (808) 487-7938. It’s Hawaii Vision Clinic Inc.’s business and passion to make sure that we all enjoy our island’s unique and spectacular beauty.