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