HUMAN LIFE A PRECIOUS GIFT

The Human Eye

Some researchers estimate that people who can see well gain approximately 80 percent of their information about the world through their eyes.  In combination with our brain, our eyes enable us to see in full color, to track moving objects and images smoothly, to recognize patterns and shapes, and to see in three dimensions. Furthermore, we can see in varying degrees of light.

The latter involves a number of complementary mechanisms.  For example, the pupil can expand from 0.06 inch to 0.3 inch (1;5 mm to 8 mm) in diameter, resulting in a possible 30-fold increase in the amount of light entering the eye. The light then passes through the lens, which focuses it onto the retina, concentrating the light energy by a factor of 100,000 times.  So never look directly at the sun with the naked eye! 

The retina, in turn, houses two types of photoreceptors-cones (approximately 6 million), which gives us color vision and high resolution, and rods (120-140 million), which are more than a thousand times as sensitive as the cones help us to see in dim light. Indeed, under optimal conditions, a rod can detect a single photon, or elementary particle of light! 

Another adaptive mechanism involves retinal neurons linked to the cones and rods.  These neurons adapt "in seconds and can improve night vision by a factor of 10 or more," says the American Optometric Association.  "Neural adaptation is rather like having low-speed and high-speed film simultaneously available in your camera." 

Engineers often design cameras, scanners, and computers, along with compatible software.  But the degree of integration and the level of sophistication attained are vastly inferior to those of  our sensory system. Ask yourself, 'Is it reasonable  to attribute our vastly superior living sensory system to blind chance, as evolutionists do?'  An ancient servant of God name Job knew little about the human body compared with what we know today.  Even so, he felt impelled to say to God:  "Your own hands have shaped me." -Job 10:8. 

Next time: HUMAN LIFE A PRECIOUS GIFT -The Human Brain

From the Awake! magazine