We explain what are the omnivores, what are their characteristics are, the case of humans as omnivorous, with examples.
What are omnivorous animals?
Omnivorous species (from the Latin “omni” => “everything” and “vorare” => “eat”) are those heterotrophic organisms that have a flexible, not specialized diet. This means that can feed on various sources of organic matter, either plants (like herbivores consume) or animal (like carnivores do), without too much distinction.
In fact, omnivores tend to feed on what is available at the time, leading to a really diversified diet. They are opportunistic eaters and general, playing the role of predator, scavenger, with vegetarian habits sometimes.
However, they should not be confused with adaptive cases in which some herbivores may eventually eat meat, or some carnivores eat plants. Omnivores are able to switch between one diet to another in a conscious way.
Characteristics of omnivorous animals
Unlike carnivores, physically and biochemically adapted to obtain and digest meat, or herbivores, adapted to a vegetarian diet, omnivores do not have particular adaptations.
They retain a non-specific biological profile, capable of feeding more or less equally on plant leaves, insects or red meat. Consequently, in many cases, they have mixed dentition, equipped with teeth capable of tearing, crushing or cutting, as is the case of human teeth.
Secondly, their digestive systems fall somewhere between the straightforward simplicity of carnivores and the delayed complexity of herbivores. In other words, they can only partially digest the most complex and difficult plant matter, which is usually directly expelled as waste.
Examples of omnivorous animals
Omnivores include all kinds of animals, including birds, such as the raven.When looking for examples of omnivorous animals, the human being is the most obvious case. There are people who want to eat only vegetables, others only meat, but the vast majority try to balance their food by eating from various sources, sometimes even insects.
However, we can also list as omnivores most bears, pigs, crows, raccoons, mice and rats, dogs, possums, certain turtles, crabs, hedgehogs, skunks, fish such as piranhas, or the reptiles of the Lacertilia family.
The human being
The human being, in all complexity, is probably the simplest example of an omnivorous animal. Human teeth are complex and mixed, the digestive system is much more complex than that of a strict carnivore, but much simpler than that of a herbivore, and is capable of nourishing from different food sources, from fruits to seeds, insects, meats, vegetables, roots, etc.
There is a debate whether we have always the same diet, or whether our species learned to be omnivorous during our evolution. It is known that our probable ancestors were omnivores too, and that many apes with which we are related usually are, the same with the herbivores that occasionally tend towards the consumption of insects or other meats.
Even so, the consumption of meat (and the invention of fire to digest it better) is considered a fundamental milestone in our evolutionary history. Fire was able to help us get an essential supplement of proteins and calories that helped us form more complex brains.
However, a diet rich in meat (especially red) has been shown to be detrimental to our metabolism, unable to deal with such a large amount of saturated fat without suffering the consequences. The debate, therefore, continues.
Carnivorous animals
Big cats are examples of carnivores.Carnivorous animals are specialized consumers, who obtain their organic matter mostly from the flesh of other animals. They are either predators or scavenger, sometimes eating each other.
They have sharp teeth to tear the meat, as well as claws, pincers, sometimes venom or other competitive mechanisms that helps them capture their prey and guarantee their daily intake of food. It is possible, on the other hand, that some carnivores supplement their diet with other types of food.
Examples of carnivorous animals are the lions, hyenas, vultures, condors, pelicans, polar bears, sharks, wolves, tigers, etc.
Herbivorous animals
Herbivores, like cows, have a much more complex digestive systems.Herbivores are the opposite of the carnivores. They consume exclusively vegetarian foods, organic matter of plant origin: leaves, stems, shoots, seeds, fruits, roots, barks, etc.
For that reason, herbivores have a specialized dentition, helping them to grind up plant fiber, but also long and complex digestive systems which allow breaking down cellulose and obtaining nutrients. This is the case of ruminants (giraffes, deers, antelopes, bisons, buffalos, etc), able to regurgitate and chew the food again until the best possible digestion is guaranteed.
Examples of herbivorous animals are the cattles, deers, giraffes, beavers, donkeys, camels, horses, koalas, mice, rhinoceros, aphids, etc.