From Prey to Predator: Energy Movement in Nature
By Greta Solbrig on October 14, 2024 in Blog
I used to struggle witnessing death. But over time I have learned that nature does not act with malicious intent, it acts with efficiency. Energy systems are constantly refueled by death and decomposition. Each trophic level extracts energy from its lower counterpart. Life taken from prey is energy transformed and invested into its predator. I know that the circle of life seems gruesome, but energy is never lost. It is conserved.
Energy is passed among layers of consumer interaction called trophic levels. At the base of all food systems sits the most important energy source, producers. Producers are organisms, like plants, that can create chemical energy through exposure to sunlight. Without producers, there would be no predator-prey interactions. Why would one organism hunt another if there were no reward? Chemical energy in plant systems is transferred up to the next trophic level each time an herbivore has a meal. You may not have realized it, but each time you stumble upon a grazing cow or rabbit feeding on your well-tended garden, you are watching this process take place. In this way nature breaks, but it will also rebuild again and again. No organism, including humans, possess an everlasting supply of energy. Everyone gets their turn, and eventually the energy will be passed along to the next temporary keeper.
While some energy is gradually lost to the environment through heat, nature will not waste what it has already invested in. The energy from producers is physically manifested in the makeup of an herbivore’s tissue, which in turn is hunted by carnivores. Carnivores will exploit any opportunity to hunt, as their source of nutrients is not as stagnant as a plant is. These meat eaters have a lot relying on their ability to catch prey, as they must expend so much energy to do so. While herbivores are considered primary consumers, carnivores and omnivores are considered either secondary, tertiary, or quaternary consumers, respectively. The less predators a species has, the higher its trophic level.
But what about the top consumers? Where does their energy go? Like all living organisms, even the top consumer’s stored energy will not go to waste. Upon their death, these species will decompose with the aid of organisms such as fungi and detrivores within the soil itself. The plant soil microbiome houses bacteria that are instrumental to the decomposition process. The decomposing nutrients will then fuel the producers growing out of the soil, and the cycle will repeat. Endlessly and efficiently.