Feathers – Complex Structures of Ingenuity

Feathers – Complex Structures of Ingenuity

We take many things for granted without realizing the complexity of their design. That is undoubtedly true of bird feathers. American biologist Thor Hanson correctly wrote that feathers are “complex structures of ingenuity that defy the most advanced human technologies.”

Feathers are made of keratin, which is a protein. They are connected to blood vessels like our hair is connected to our vascular system. Once a feather reaches its final stage, it is disconnected from the blood vessel that has nourished it, reducing the weight of the feather. When molting occurs, and old feathers are discarded, the vascular system is re-connected by tiny muscles surrounding the feather follicles to grow a new feather.

These same muscles allow a bird to move its feathers for various purposes. Feathers serve the bird by providing insulation, waterproofing, color, display, and flight. Birds accomplish each of these functions in remarkable ways. Peacocks can present colorful displays, but so can parrots, pheasants, and various tropical birds.

Feathers provide insulation by trapping air, which is a poor conductor of heat. Down feathers trap air efficiently while adding very little weight to the bird. This same feature gives waterfowl their buoyancy while giving them insulation. Birds preen their feathers by treating them with oil from a gland just above the bird’s tail. The tight interlocking barbules in a bird’s outer feathers make them impenetrable to water. Birds use down to produce an environment that allows eggs to hatch and to keep chicks safe. Modern technology can’t match the heat-to-weight ratio of feathers.

Flight is possible because each wing feather has the shape of an airfoil to provide lift and minimize drag. Since the feathers are flexible, they can move to reduce drag, and their tips are designed to minimize turbulence making smooth flight possible. They really are complex structures of ingenuity.

Color in bird feathers is accomplished in several ways. For some feathers, melanin gives color to the feather’s keratin, and the structure of keratin is such that the bird’s diet can control its color. A flamingo’s pink color comes from eating algae that have carotenoids in it. Rather than using pigments, many brightly-colored bird feathers use structural color produced by manipulating light waves to create blues, greens, and iridescent colors.

Considering the complex structures of ingenuity we know as bird feathers brings to mind Psalms 9:1, “I will praise you, Lord, with all my heart; I will show forth all your marvelous works.” Feathers are among those marvelous works.

— John N. Clayton © 2023

References: For more amazing information about feathers, see Thor Hanson’s book Feathers: The Evolution of a Natural Miracle, published by Basic Books © 2011, and Noah Stryker’s book The Thing With Feathers, published by Riverhead Books © 2014.

Eliminating Pigments in Paint

Eliminating Pigments in Paint - Blue Morpho Butterfly
Blue Morpho Butterfly

What if we could reduce environmental problems by eliminating pigments in paint? Creating colorful paint without pigments is possible by copying something found in the natural world. For example, butterflies, birds, fish, and cephalopods use structural color to create their dazzling beauty. Light, rather than pigments, creates structural color.

Debashis Chanda and colleagues at the University of Central Florida have researched eliminating pigments in paint by using structural color. Pigment colors are artificially synthesized molecules, requiring different chemicals for each color. Structural color involves producing a geometrical arrangement of two colorless materials to make any color of the rainbow.

Chandra’s work produces a plasmonic paint using nanoscale structural arrangements of aluminum and aluminum oxide, both of which are colorless. Structural color controls the reflection, scattering, or absorption of light based on the geometrical configuration of the nanostructures. The research has placed these structural color flakes in a commercial binder to produce all the colors visible to the human eye.

Unlike pigment color, structural color never fades. Another advantage is that it reflects infrared radiation, so the material under the paint can stay 25 to 30 degrees F cooler than with chemical paint. Also, plasmonic paint is lighter weight because it can produce saturated colors with a thinner paint layer. In addition, since the colors will not fade, there may not be a need to repaint as often. Finally, eliminating pigments in paint reduces chemical substances that can cause environmental impacts.

With these advantages, structural color plasmonic paint may be the paint of the future. Interestingly, structural color is another thing we learn from studying the natural world. Often the colors we see in living things come from structural color rather than pigments. This is one more example of the intelligence God built into the world. We continue to learn exciting new ways to improve people’s lives by mimicking what God has already done. Like velcro, penicillin, bird wings, and lizard lungs, we are blessed by copying God’s design.

— John N. Clayton © 2023

References: National Science Foundation Reports and the journal Science Advances

Structural Color in Plants

Structural Color in Plants - Viburnum tinus
Viburnum tinus berries

When you see a peacock with brilliant green in its feathers, realize that it has no green feathers. Its feathers are actually brown, but God has used a clever optical trick to make them look green to us. We call it structural color. Likewise, many butterflies have bright blue spots on their wings, but there are no blue pigments in a butterfly’s wings. 

Some plants produce fruits that look blue to us without having any blue pigment in the fruits. The only plants known to produce blue fruits in this way are Viburnum tinus and Lantana strigocamara. You will not get a blue stain if you crush their berries in your fingers. On the other hand, if you crush a common blueberry, its blue pigments will stain your fingers.

When you see a blue pigment, it is blue because it absorbs all other colors while reflecting blue. Structural color uses microscopic pyramid-like structures that manipulate the light. Since blue light has higher energy than other colors, it escapes the structure. Structural color requires no pigments, and you might call it an optical illusion.

Color is essential in the natural world. For example, animals with color vision use colors to camouflage, attract others, or discern whether something is good to eat. The problem with using pigments to produce color is that the chemistry to get a particular color is quite complex, but structural color does not involve any chemistry. 

People have used chemicals to produce the colors we see in our fabrics, but some colors can be costly and time-consuming to produce. God has created a chemical-free method to produce much of the beauty we see in the world around us. Beauty in structural color gives evidence of a wise Creator.

— John N. Clayton © 2022

Reference: National Science Foundation Research News

Relationship Between Fruits and Birds

Relationship Between Fruits and Birds demonstrated in Viburnum tinus fruits
Viburnum tinus Fruit

There is an essential relationship between fruits and birds. We all know that birds eat fruits, but we may not be aware of the system’s complexity and how it varies from place to place.

Here in Michigan, we struggle with poison ivy, and I am very sensitive to it. When I moved into my present house, the property was covered with a great deal of poison ivy. I spent most of our first summer eradicating it. The following spring, I found new poison ivy plants coming up in places where there were none the year before. One of my biology teacher friends informed me that birds eat the berries of poison ivy, and they plant many of the seeds resulting in a new crop. That makes it hard to eradicate.

An August 17, 2020, report by the National Science Foundation told about a study of an evergreen shrub found in the U.K. and most of Europe. This plant, called Viburnum tinus, stores fat in the cells of its fruit, making it an ideal food for birds’ survival success. The fruit also contains a large number of seeds. The fat, or lipids, in the fruit’s cells, give it structural color, making it a very bright blue. Structural color is not made from pigments, but it is produced by internal cell structures interacting with light. The feathers of many birds, including peacocks, and the wings of butterflies have structural color, but it is very rare in plants.

Miranda Sinnot-Armstrong of Yale University says that they used electron microscopy to study the Viburnum tinus fruits’ cell walls. She said they “found a structure unlike anything we’d ever seen before: layer after layer of small lipid droplets.” Because of the lipids, these plants supply the fats that birds need. Their shiny metallic color signals the birds to lead them to this nutritive source.

The more we study the natural world around us, the more we see incredibly complex structures to allow life to exist. This is not an accident but a complex set of systems to provide diversity in the natural world. The relationship between fruits and birds is designed to give the birds a way to find nourishment and to support their food sources in a symbiotic relationship. It’s another example of God’s design for life.

— John N. Clayton © 2020

Beauty in Structural Color

Beauty in Structural Color on a Peacock
Some of the most beautiful colors you will see are found in birds and butterflies. We usually think of color as coming from pigments or dyes which reflect specific colors of light. However, the most intense and beautiful colors in the feathers of birds and the wings of butterflies don’t come from pigments. These animals display beauty in structural color.

Microscopic structures create structural color within the bird’s feathers or the butterfly’s wings which interfere with the frequencies of visible light. For example, the pigment in a peacock’s feathers is brown, but when you look at a peacock, you see blue, green, and turquoise in unusual patterns. Structural color can create color effects more intense than pigments, and structural color doesn’t fade like pigments. Structural color can even create an effect called iridescence in which colors change depending on the viewing angle. You can see this effect when you look at a CD or DVD.

What is the purpose of the colors in birds? The purpose may be for camouflage, to attract mates, or to indicate dominance. But in many cases, the colors seem to give no advantage. The beautiful colors merely exist for the beauty. When there is no evolutionary advantage for the colors, how did they get there? We humans appreciate beauty and enjoy looking at the beautiful colors. Could it be that colorful birds and butterflies were created by a Designer who is an artist who loves beauty, and who created us in His image. Could it be possible that God created the beauty in structural color for us to enjoy?
–Roland Earnst © 2018

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

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