The animals omnivores are those that feed on almost anything, ie, they can eat the flesh of other animals or parts of some plants. Examples of omnivores are the bear, the turtle, the raccoon, the chicken or the human being.
Omnivorous animals are characterized by being capable, through their digestive system, of absorbing nutrients derived from other animal tissues or plant tissues. In short, they have a “mixed” intestine, as if it were the mixture between the intestine of a carnivorous animal and a herbivorous one.
Omnivorous animals need to consume both types of food in order to survive, which means that following strictly carnivorous or herbivorous diets could have negative consequences on their growth and development.
What are omnivorous animals?
Omnivorous animals are distinguished from herbivores or carnivores in that they can eat both meat and vegetables.
The body of an omnivore cannot survive on meat alone, since its digestive system requires fiber and other mineral and organic nutrients provided by plants. Also, you need to eat foods high in calcium to keep your bones healthy.
Many animals in nature are omnivores. However, they are often classified as strict herbivores or carnivores, since their eating habits are described based on a few observations that are made of the animal in its natural habitat.
The diet of animals and humans varies widely depending on the time of year, not only because of seasonality, but also because of short-term weather conditions and the availability of food in the place where they are found.
Characteristics of omnivores
The physical traits of omnivorous animals result from a combination of the characteristics of carnivorous animals and the characteristics of herbivorous animals.
However, there are several characteristics that are common to all omnivores:
In their teeth they have incisors or fangs and flattened teeth.
The incisors use them to tear through flesh and flat teeth to grind plants and seeds. In these teeth, the fangs or incisors are not as large and sharp as those of a carnivorous animal.
Omnivorous birds, like chickens, have a specialized digestive sac for grinding food called the gizzard. The gizzard is muscular and is usually filled with stones by the animal itself to facilitate the grinding of food before it reaches the intestine.
Generally, the digestive system of omnivores has a single stomach and intestines with an intermediate length between herbivorous animals and carnivorous animals.
The digestive system of an omnivore is much simpler than that of a herbivore, but more complex than that of a carnivore, so it can dissolve and take advantage of the nutrients in vegetables to some extent.
Very diverse group
We can say that all omnivorous species share at least these two characteristics, but we could not point out many more in common, since they represent an extremely diverse group of species, ranging from insects, amphibians, fish, reptiles and birds to mammals.
Likewise, it should be noted that omnivorous animals have a great evolutionary advantage over herbivorous and carnivorous animals, since they can adapt more easily to environmental changes that occur in their environment.
Examples of mammals omnivores
There are many species of bears, some of the best known being the American black bear or the European brown bear. So, depending on the area in which you live, your diet will be one or the other.
What they do tend to have in common is that most of them base their diet on plants (roots, shoots, berries, bamboo, etc.), but they also eat other mammals, fish or insects.
Orangutans have a preference for fruit, as they love sugar. In addition, they usually take berries, insects, leaves or seeds.
The closest living relative to humans eats mainly plants and fruits. However, they also need to ingest other mammals, insects, larvae, eggs, and even carrion.
The coati has a varied diet, which includes different vegetables (leaves, berries, seeds, fruits) and animals (insects, snails or small vertebrates such as snakes, frogs, rodents or birds).
The squirrel is one of the most widespread animals in the world, so its diet will vary according to the region it inhabits. In common, they consume many nuts and seeds (pineapples, walnuts, chestnuts, acorns, pine nuts, pecans), but they also eat vegetables, legumes, fungi, insects, fruits or larvae.
The skunk is an animal that has no problem eating any digestible product that is found. Their diet includes plants, insects, fruits, berries, seeds, larvae, honey, small mammals, birds, or eggs.
Ground hedgehogs feed mainly on fruits, vegetables, and small insects. Remarkable is how they ingest the fiber and chitin of the exoskeleton of some insects such as beetles, grasshoppers or snails.
Raccoons are omnivorous animals that especially enjoy fruits, beef, chicken, turkey, and fresh fish. In cities near forests they are very commonly seen scavenging garbage and restaurant waste in search of food.
Each raccoon is endowed with a set of at least 40 teeth, with four long fangs that make it easy for them to tear animal flesh. In addition, in the same teeth they have large molars and premolars to grind vegetable and fruit tissues.
The dog, one of the first domesticated animals, feeds mainly on what its owner provides, generally being feed and processed products. Biologically, the dog would feed mainly on meat and fish, accompanied by vegetables and other vegetables.
One of the animals that has the least filters when it comes to ingesting any type of food. They feed on other animals and insects (live or dead), plants, berries, fruit, vegetables, excrement, tree bark, garbage and even other pigs, being cannibals if the need requires it.
The wild boar is a strong predator, so it can feed on any mammal, bird or insect. In turn, it also feeds on plants, eggs, berries, fruits or seeds. He would also have no problem eating carrion or garbage.
It is one of the most voracious animals in nature, being able to use its aggressiveness to get any type of food. They can take leaves and stems of plants, insects from stones or attack antelopes and other mammals of a certain size to satisfy their hunger.
There are many theories that propose that, in reality, the human race is vegetarian due to its long intestine and the small fangs that our teeth have. However, the first records of Homo Sapiens reveal that humanity’s diet has been omnivorous since its inception.
In the archaeological sites of the first Homo Sapiens , many archaeologists have found what appear to be tools probably used for hunting and the consumption of meat in the places where they lived.
Our ancestors have been portrayed in history as “opportunistic consumers” who survived with the resources available when and where they were needed. Furthermore, the discovery of fire and its use to cook food and facilitate its digestion undoubtedly established a great advantage.
Other omnivorous mammals
Examples of omnivorous birds
Chickens eat cereals such as corn, other seeds, and insects and worms that peck at the ground. Therefore, in many domestic poultry houses, they are fed organic waste from food cooked at home, including bones and meat scraps.
Chickens have a powerful beak to break and tear parts of almost anything, even breaking pieces of bones and fish bones. In addition, it must be said that the digestive system of chickens is highly specialized to soften hard foods.
The emu bases its diet on the ingestion of plants, seeds and shoots, but it is also common to see it hunt some insects to include them in its diet.
The hummingbird, like some insects such as bees, feeds mainly on the nectar of flowers. However, it is also common to see it ingest pollen, sap, and small insects such as fruit flies, spiders or mites.
Although it is not a particularly large bird, it is very powerful when it comes to hunting rodents, amphibians, crustaceans or some reptiles. This meat is complemented with vegetables such as berries and fresh fruit and carrion or garbage waste.
By not having anything that allows it to chew, the ostrich must ingest everything that allows it to enter through the beak and down the throat. Berries, seeds, rodents, and other small mammals make up their main diet.
This bird varies its diet according to the time of year, however, it tends to feed mainly on insects (larvae, ants and those it obtains from tree wood), sap, nuts, seeds or fruits (including juice).
Other omnivorous birds
Examples of omnivorous reptiles
Although it may sound strange to some, turtles are considered omnivorous animals.
During the first few years of life, many wild and domestic tortoises are exclusively carnivorous, but as they develop and grow, their intestines acquire the ability to process fruits and vegetables.
Domestic tortoises are usually fed only vegetables, but in reality they require high protein nutrients during their first 5 years of life to develop properly.
They often dig the earth in search of worms and insect larvae to obtain the missing proteins in their diet when they are not well fed.
Other omnivorous reptiles
– Sahara spiny-tailed
lizard – Balearic lizard
Examples of omnivorous fish
Aggressive fish that, due to its strong teeth, can feed on other fish of similar or larger size to its own, as well as crustaceans or invertebrates . It also bases its diet on the intake of insects, seeds or aquatic plants.
Predatory fish that varies its diet depending on the maturity it reaches. When small it feeds on small invertebrates and, as it grows, it can hunt prey such as fish, frogs, crabs or even ducks. It also feeds on aquatic plants and algae.
Angelfish or climbing
Very popular fish in home aquariums. In the wild, it feeds on small fish, sea worms or some sea vegetables. In fish tanks, owners often feed them brine shrimp, worms, or scales.
Other omnivorous fish
Examples of omnivorous animals insects
Voracious animal with little filter when feeding. It is a scavenger and can feed on insects of equal size to sewage and organic products discarded by man. In any case, he prefers sweet foods and meat.
Flies have a predilection for spoiled meat, sugary products, and feces. They tend to prowl around areas with decaying organic products. Also, some can suck blood.
Many species of ants are physiologically adapted to feed on plant leaves, roots and nectar, but in extreme situations they can also feed on prey that they catch when there are no plants nearby.
Using their powerful jaws, ants can catch other insects and sever parts of their body for ingestion.
In ants, carnivorous feeding occurs when there is a shortage of plant food, such as leaves or seeds. They attack other insects in groups, dissect them with their jaws and ingest small portions of their prey.
Other omnivorous insects
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