The sun is vital for plant and animal life to exist on Earth. It is our ultimate energy source, affecting all aspects our lives from the food we eat to the air we breathe. It all begins with the action of the sun on plants, and the benefits imparted are then disseminated throughout the animal kingdom.
Energy to Grow and Thrive
Energy is one of the most important benefits of the sun for animals and plants. Sunlight is essential for plant life. Plants use the sun's energy to sustain themselves by producing sugars and other nutrients. Animals then consume the plants and convert the plant's energy (which came from the sun) for their own use. In the animal world, herbivores (plant eaters) get all their energy directly from plants. Carnivores (meat eaters) get their energy from plants indirectly, by ingesting the animals that ingest the plants. Omnivores (plant and meat eaters) get their energy both ways. But all, ultimately, get energy from the sun.
Another important benefit of the sun for animals is oxygen. Animals need oxygen to breathe, and plants provide it. But it is the sun that induces plants to make oxygen. Plants convert the sun's energy into glucose and store it for their use in a process called photosynthesis. The byproduct of photosynthesis is the release of the oxygen all animals need to survive.
Regulation of Cycles
The sun benefits plants and animals by regulating their cycles, in both the short and long term. Plants respond to changes in the length of day, or the amount of sunlight available. They open or close, flower or go dormant according to the schedule set by the sun. Less sunlight and shorter days trigger the growth of lighter fur colour for some animals, camouflaging them from predators in winter, while more sunlight and longer days will trigger the growth of darker fur for summer camouflage. Hibernation is also triggered by the amount of sunlight reaching the earth, as are mating seasons and migration patterns.
Sunlight, absorbed by plants and animals, generates vitamin D, which is essential for healthy growth. Vitamin D confers benefits for animals by aiding calcium-driven body processes such as the formation of strong bones and teeth. Both plants and animals can make vitamin D within their bodies but only with exposure to sunlight.