Throughout the natural world, we see special design features that allow animals to survive in environments that place unique demands. Chameleons have an eye-brain connection that enables the eyes to rotate independently of one another or work together when needed. Chameleons use their tongues to catch insects, but to capture their food, both eyes must work together to overcome depth perception issues. At the same time, chameleons are very vulnerable to predators, so their eyes must rotate independently to look in several directions at once. We find another example of unusual eyes in the genus of four-eyed fish, Anableps.
Anableps live in northern South America and Trinidad, where they swim in the surface waters of lakes and rivers. Near the surface, they are easy prey for birds, so they need to see above and below the water simultaneously. They appear to have four eyes, two above the water surface, and two below the surface. In reality, they are not separate eyes. The eyes are divided into two sections, separated by a band of tissue.
Each section of the Anableps eyes has two corneas, two pupils, a single egg-shaped lens, and one retina that is also divided. The portion of the eyes located above the water connects to a different section of the fish’s brain than the area below the waterline. These four-eyed fish are ideally suited to fill an ecological niche that no other fish can.
You might think that all fish could use this design, but every ecological niche has animals designed to inhabit and maintain that location. Anableps are unique, and that makes them popular aquarium fish. More importantly, this unique design speaks of God’s imaginative creativity in providing full use of every resource on planet Earth with creatures like the four-eyed fish, Anableps.
We are frequently astounded by what animals can do. As science seeks solutions to problems such as having enough food, knowing how to avoid disasters, and solving medical problems, we frequently see the answers in the designed features of living things. There are many things we can learn from the animals.
How can we have enough food to feed everyone on this planet? One way is to take advantage of animals with high reproductive capacity. A female mackerel, for example, lays about 500,000 eggs at one time. We have relied on animals like cattle which have one offspring at a time, are environmentally unfriendly, and require massive energy to sustain. Many fish, arthropods and mollusks can reproduce massive numbers of offspring, need very little energy input, and give off little or no environmental hazards. Some of them even remove environmentally unfriendly materials.
Can we improve our vision and perhaps restore sight to people who are blind? Studies of the common dragonfly have shown that each eye has 30,000 lenses. Our one lens is limited as to what we can see. The way images are transmitted to the brain in animals allows multiple transmissions. We are learning from insects and chameleons how the brain can reconstruct a useful image from many separate images. A chameleon can move its eyes in different directions, and its brain can interpret the direction and identification of what each eye is seeing independently.
How can we make stronger materials? Beaver’s teeth are so sharp that Native Americans used them as knife blades. The structure of the tooth enamel in the beaver and how the teeth maintain their sharpness is an area where materials science researchers can learn from the animals.
Can we make better drones? Researchers are interested in how high-frequency wing beats can allow better control of flight. Tiny flies known as midges beat their wings over 1000 times a second – twice as fast as mosquitoes. We can even learn from the animals that are almost too small to see.