Tag: pigment

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Incredible Color

Incredible Color
Our ability to see the incredible color in the world around us is amazingly complex. We don’t actually see color with our eyes. We see color with our brains.

Most humans have trichromatic vision. Our eyes only detect red, green and blue. If our eyes detect a lot of red and green but not much blue, our brains decide that we are seeing yellow. When our eyes register equal amounts of red, green, and blue, our brain decides that we are seeing gray. If red and blue are present, but not much green, our brain decides we are seeing purple.

Some of us do not have red or green receptors in our eyes, especially people with XY chromosomes (males). We call it color blindness, but in reality, our eyes just don’t see one particular set of wavelengths. Some of us with XX chromosomes (females) may have tetrachromacy which means we see more than the three primary colors.

In the animal world, color is produced by many different techniques. The wings of the Morpho butterfly appear to be blue or violet depending on how the light strikes them. This is due to light-scattering scales that cover the insect’s wings. Dragonfly wings look similar to the Morpho wings, but the dragonfly’s color comes from waxy crystals that cover layers of the pigment melanin. We call the method of color production in these insects “structural color” because it is produced by the structure of the material rather than by pigments. Cameleons also use structural color using nanocrystals in their skin. They can tune the nanocrystals to reflect different colors. In this way, they can match the color of their environment or their mood.

We use color in many different ways such as camouflage, disguising foods to avoid their natural look, and to identify things. Much of the color that we see in the world has no practical value. For the most part, beauty is not a survival attribute. Evolutionary models attempt to explain some of the coloration we see around us, but in many cases, color is not a survival factor. Incredible color may be simply an expression of God’s desire for us to see the beauty and the majesty of His creation.
–John N. Clayton © 2017

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It’s Good to be Blue

It's Good to Be Blue Begonia Leaf
It’s a plant that uses quantum mechanics to make maximum use of minimum light, and in doing so, it displays blue leaves. The explanation of why blue begonias are blue is another demonstration of the incredible design built into all living things.

The tropical begonia (Begonia pavonina) that grows in Malaysia has leaves that are iridescent blue. The blue does not come from pigmentation, but rather from structural color, a technique that gives beautiful color to some birds, Butterflies, and beetles. In the leaves of all kinds of plants there are cellular capsules called chloroplasts, and inside those structures is a green substance known as chlorophyll. The chloroplasts are the organic machines that take energy from sunlight and chemicals from the soil to make organic energy that allows the plant grow.

Sunlight is a mixture of light at various energy levels, but green is the highest energy of sunlight reaching the surface of the Earth. Since the chlorophyll pigment reflects green light, the plant is protected from being damaged by the high-energy sunlight. We see the reflected green light, so the leaves look green.

Blue begonias live on the floor of dense rain forests where the forest canopy restricts the light. Inside the chloroplasts of these begonias, there are nano-structures called thylakoids where the energy conversion takes place. Other plants have thylakoids, but they are arranged differently in the begonia. Scientists using an electron microscope discovered that the thylakoids are aligned in a way that they act like crystals. In other plants, they are haphazard in their arrangement. Light bounces around within the thylakoids causing interference at certain wavelengths and reflecting the iridescent blue. The light is slowed down in this process so the plant can use more of the high-energy green and red light while reflecting the blue. These plants are using principles of quantum mechanics which scientists only began to learn about in the twentieth century.

The result is that the blue begonias get the nutrition they need to survive in a location with little sunlight, and we see the leaves as a beautiful blue. One science website described the alignment of the thylakoids in this way: “…they have an amazingly regular structure, which is obviously planned.” Here is the way another science website described the unique way these begonias efficiently use the limited sunshine they receive: “It seems selective evolution led the plants to engineer a nanoscale light-trapping structure, the likes we’ve only seen in miniature lasers and other photonic structures made by humans…”

We believe that planning requires a planner and engineering requires an engineer. As scientists study even the simplest forms of life, they find more and more evidence that God is ingenious in all He creates.

–John N. Clayton and Roland Earnst © 2017