Colors of Fall and What they Mean

Colors of Fall and What they Mean

The beauty of autumn’s brilliant colors is an amazing testimony to the creative wisdom of God as well as an expression of His love of beauty. The colors of fall are caused by several pigments and the interaction of sunlight and sugar.

Most of us know that chlorophyll makes leaves green. When leaves receive reduced sunlight in the fall, they also have a reduced supply of nutrients and water, causing the chlorophyll to be removed. The chlorophyll masks two pigments that have different colors. Carotene is yellow, and several varieties of anthocyanins are red. Many leaves contain tannin, which is brown and is dominant in oak trees. Sunlight acting on trapped sugar also produces anthocyanins with various sparkling colors, which is why the color is so spectacular on a sunny autumn day in a maple forest.

As the days grow shorter, the reduced amount of sunlight causes a corky wall called the “abscission layer” to form between the twig and the leaf stalk. This wall will eventually break and cause the leaf to drop off in the breeze. The corky material seals off the vessels that supplied the leaf with nutrients and water and blocks any loss of sugars from the plant.

What is especially interesting is that the leaf colors are not all the same. Some vines produce spectacular colors. Poison ivy takes on a beautiful red due to a high concentration of anthocyanin. Aspen has a high concentration of carotene producing the vivid yellows which dominate the woods in the Rocky Mountains. In Michigan, we have maples, gum, aspen, and oak, giving us spectacular colors that vary from one location to another.

The colors of fall are a great testimony to the fact that God paid attention to aesthetics in the creation. If survival of the fittest were the only criteria for choosing the chemicals that allow plants to survive, it seems that there would be one best choice. Different chemicals provide a vivid, beautiful splash of color for humans to enjoy. Beauty is not part of the evolutionary model, but it speaks of God’s creativity, giving us a wonderful and beautiful world in which to live.

— John N. Clayton © 2020

Sunlight Affects Life Cycles

Sunlight Affects Life Cycles

One of the wonders of life on planet Earth is the influence of sunlight. As winter fades away and summer approaches, we see all kinds of changes in life. As scientific research continues into the wonders of the animal and plant kingdoms, we see more carefully designed biological systems. Here are some examples of how sunlight affects life cycles:

COCCOLITHOPHORES: These are tiny phytoplankton plants that live in the ocean. As the season changes and the Sun warms the waters, those organisms increase their rate of reproduction. They would smother themselves with overcrowding except for the fact that they give off dimethyl sulfide. That chemical rises into the atmosphere and oxidizes into solid sulfate particles. For raindrops to form, there must be moisture, cool temperatures, and condensation nuclei. The solid sulfate particles provide the condensation nuclei, and the rising air cools the moisture from the sea resulting in clouds. The clouds block the sunlight, thus cooling the sea and slowing down the reproduction rate of the coccolithophores and avoiding a massive die-off. This phytoplankton literally manipulates the weather to ensure its own survival.

SALMON. These fish know when to return to the waters of their birth to spawn. Built into their bodies is a pineal gland that stimulates the pituitary gland, triggering an urge to spawn. Navigation tools designed into the salmon allow them to find the place of their origin where they spawn and die.

BEAN APHIDS AND OTHER ANIMALS. Bean aphids give birth when the length of the day reaches 14 hours and 55 minutes, assuring that the offspring will have warmth. Similar triggers by sunlight affects life cycles, allowing muskox to shed their insular undercoat, mallard ducks to shed their winter down, and snowshoe hares to change their color from white to brown before all the snow melts.

FROM FRUITFLIES TO HUMANS. Fruitflies shed their pupal husk an hour before dawn even when kept in the dark. Even when kept in total darkness, hummingbirds slip into torpor at dusk, allowing them to conserve energy. A poppy folds its petals at dusk, even in a dark box. Both the hummingbird and the poppy will resume operations at dawn, even in the darkness. Scientists are still researching what triggers these changes even without sunlight. Medical researchers are also studying how humans respond to a lack of sunlight, causing seasonal affective disorders (SAD).

Studying the incredible ways in which sunlight affects life cycles on Earth is a great way to grow in appreciation for the creation process. We marvel at the careful design built into all living things. David looked at himself and his world and remarked, “I will praise you, for I am fearfully and wonderfully made: marvelous are your works…” (Psalms 139:14).

John N. Clayton © 2020

These examples were found in National Wildlife magazine Volume 32 # 1.