Over time, an organism could develop the means of eating things that have never been eaten before. Our diets are a crucial part of our survival because we have evolved to consume a particular group of things to supply our bodies with energy and nutrients.
The diet of animals is as varied as the number of animals that live on the Earth. Humans are omnivores capable of being either herbivores or carnivores, depending on certain things like medical issues or social preferences. We can eat almost any plant or animal that does not pose a biological threat to us, like toxins or poisons. There are organisms that are more restrictive in their diets and can only eat a particular thing, like anteaters that eat only ants or whales that eat large quantities of plankton. There are even organisms that are capable of eating inorganic things, like plastic or metals.
These highly unusual organisms are an opportunity for scientists to develop ways to combat human excessive plastic use and disposal. Turtles, one of the world’s most known creature, are composed of numerous species that are capable of eating both plants and animals, depending on the species and age group.
Turtles belong to the order Testudines and are reptiles composed of a bony or cartilaginous shell from their ribs that form their “shells”. This includes both freshwater and saltwater turtle species as well as all existing and extinct species. Among the Testudines order are tortoises as well. The main distinction between turtles and tortoises is that tortoises are land animals only while turtles are mainly aquatic that may or may not go to land. Researchers estimate that the ancestors of turtles, a sort of proto-turtle, appeared about 220 million years ago.
Species from Testudines have appeared as early as 137 million years ago, which makes them one of the oldest reptiles in the world. One of the stables of turtles, their shells, evolved as early as the proto-turtle and became successful because it gave the species stability and safety. Aside from their shells, turtles are known for the retraction of their heads, which occurs in two groups: those that retract backward and those that retract sideways.
There are over 300 species of turtles and are composed of a variety of sizes, behaviors, and diets. Turtles are highly adaptive and can be found all over the world except for Antarctica. The largest turtles species are the leatherbacks, which can become as large as 1,500 lb and over 5 ft. The smallest is the speckled Cape tortoise, which can be as big as 3.1in and weigh up to 6oz. Turtles and tortoises are famed for their ability to live long with some being recorded to live over 100 years or more.
This is due to many factors, including a slow metabolism, ability to not eat for extended periods of time, and their defense against predators (the exception being humans). Recently, researchers have discovered an additional factor in the turtles long age. They found that the organs of turtles do not gradually break down or become less efficient over time, which is what happens to almost every other animal. The found that the lungs and livers of older turtles were indistinguishable from samples of their younger selves. This gives them lots of time to watch the world and eat.
The Turtle’s Diet
The amount of turtle species and their adaptive nature means that their diet is highly diverse. Most turtles are omnivores, eating different sea plants and invertebrates. The common musk turtle, which is kept as pets, eats things like mollusks, small snails, small fish, and insects. They occasionally eat plants. Since they are kept as pets, they also eat pelleted turtle food, composed of nutrients specifically for turtles. In contrast to the musk turtles, the cooter turtles consume mainly plants with the occasional insect.
While most adult turtles can be carnivores, herbivores, or omnivores, the juveniles are primarily carnivores because they have a high demand for protein. The protein is essential to their growth. The green sea turtle has kids that are carnivores but the adults are herbivores. They are the only adult herbivore species.
The leatherback sea turtle is also unique among turtles because they primarily eat jellyfish. Because they are the largest species of turtles, their diets must accommodate for their size. They consume the larger jellyfishes and in large amounts.
They are capable of eating other soft-bodied organisms, but their preference is jellyfish. Pacific leatherbacks have been known to travel over 6,000 miles from Indonesia to California because they want to eat California jellyfish. Unfortunately, this contributes to the endangerment of the leatherbacks because they mistake plastics in the water for jellyfish and eat it. The consumption of plastics lead to their untimely deaths and drive them towards extinction since they are already an endangered species due to humans.
Many sea turtles consume plastics because they mistake it for food. This leads to several problems. The plastics can obstruct their digestive tracts and starve them over time. The plastics can also lead to nutrition dilution because they consume plastics and become full despite not having consumed any nutrients. This stunts their growth as well as lead to malnutrition and other detrimental health conditions, which leads to their deaths.
The stunted growth also means that they reach sexual maturation more slowly and at later times in their life, which results in additional population decreases.It is important to continue to study and understand turtles. Understanding their genome could someday allow humans to extend our own lives and help us to prevent degradation of our bodies. Understanding their diets, behaviors, and distribution would allow us to know the areas of the world that need protecting and regulation.
Conservation efforts to save turtles begins with understanding the human use of plastics and where they are disposed of so that we can prevent their introduction into the ocean or at least try to remove them. Hopefully, we can one day be able to admire turtles without the risk of extinction.