Relationship Between Fruits and Birds

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