Are Insects Animals? Understanding The Classification Process

Rajnandini Roychoudhury
Feb 20, 2023 By Rajnandini Roychoudhury
Originally Published on Oct 25, 2021
Fact-checked by Vikhaash Sundararaj
Collection of variety of insects

Did you know that house flies are animals?

Wait, how is that possible? Are they not insects?

Yes, house flies are insects. However, insects are animals, which makes this species an animal. Most of you are confused because of the tendency to view mammals and animals synonymously. So, it is hard to accept insects like ants, moths, bees, wasps, butterflies, and other similar organisms as an animal.

Insecta is a class within the kingdom Animalia, which belongs to the arthropods phylum. Among arthropods, it is the most successful class of animals.

These invertebrates are the only arthropods that have evolved to have wings. This evolution has a crucial role to play in the growth and development of this group of arthropods. Today, the insect species is the largest group of animals found in the world.

Interested to know more about this animal? It is time to dwell deeper on why this species is known as animals. Some more cool facts like how do insects breathe? And what do insects eat? Can be found on Kidadl.

Insects Are Classified As Animals

Insects are a class within the kingdom Animalia. How? Because like every other animal, they can move, have multiple cells, breathe oxygen, reproduce, and eat organic matter.

When it comes to the classification system, insects are members of the animal kingdom and belong to the phylum Arthropoda. Arthropods can be described as an animal with jointed bodies, an exoskeleton and a segmented body that includes a head, abdomen, and thorax. The Arthropoda phylum is divided into four classes, of which Insecta is the most successful one.

The Insecta class form has six legs, exoskeletons, a pair of antennae, and a body segmented into three parts. Lacking a backbone, insects fall under the category of invertebrates. On the other hand, humans, fish, birds, mammals, and more are vertebrates.

Insects are invertebrates with wings (well, most insects have wings). The physical ability of these species developed a million years ago has led them to colonize the world. That is why 75% of the animal world comprises insects.

The Insecta class has 29 orders and some common insects include praying mantids, cockroaches, butterflies, moths, grasshoppers, katydids, crickets, wasps, bees, ants, sawflies, flies, beetles, and termites. Research suggests how insects play some critical roles in the environment, they pollinate, decompose, control pests, and indicate the quality of an ecosystem.

Small in size, most insects tend to be less than 0.2 in (0.5 cm) long. However, some insects can be as long as 10.7 in (27. cm).

The difference between the sexes is quite prominent and much better identified with knowledge of the body structure of one sex. The life span of an insect can vary between a mere two hours to 50 years. Scientists understand the difficulty in estimating the population of insects in a specific area.

Lastly, as an animal, insects can be found in most habitats, from land to freshwater. This is the reason why they can be found in a large number around the world.

Insects As The Most Successful Group Of Animals

The class, Insecta, has more species than any other group in the animal kingdom. They have successfully colonized different habitats across the world. It is the species’ ability to fly that is responsible for this feat.

The Animalia kingdom has many groups, but none are as successful in comparison to the class Insecta. Since their first appearance in the Devonian period, there are now more than a million insects across the Earth.

Thus, insects take the top spot among the animal kingdom when it comes to the number of organisms. But how was this possible? How were such tiny beings able to colonize most areas of the Earth?

It became possible when insects adapted to flying in the Permian period that was around 285-245 million years ago. Due to this evolution, this class of Arthropoda was successfully able to conquer diverse habitats except for places with freezing temperatures or near volcanoes.

The gift of flight has allowed insects to inhabit new locations, escape predators, successfully mate, and find food at a speed not possible for other flightless animals.

Animals And Insects Are The Same

An insect is a group among animals, but the kingdom of animals includes other organisms like humans, birds, mammals, and fish.

What makes insects, animals are five key aspects. These aspects are what distinguish animals from plants, eukaryotes, and fungi.

Insects are animals because they can move around. In the case of insects, they can both walk with their legs (like most mammals), and fly with their wings (like most birds).

This dual ability has allowed them to conquer different landscapes from forests to deserts. The only places you won't find insects are in places with freezing temperatures or near volcanoes.

Insects are animals because they are multicellular. This means that this species like other animals are made of more than one cell. Every cell plays a role in the insect's body.

Insects are animals because they breathe oxygen. Insects do not have lungs; instead, oxygen enters their body through spiracles and tracheae. Tracheae are the tubes through which oxygen is obtained and carbon dioxide is expelled. Oxygen is delivered to this animal's cells via the tracheae.

The amount of oxygen intake depends on the concentration of oxygen in the surroundings. These tubes are connected to the body via spiracles. The number of spiracles on an insect's body varies, with some animals having none at all.

Insects are animals because they reproduce. Insects are able to reproduce and multiply quite quickly. Both sexual and asexual reproduction takes place in insects.

In the former, both the male and the female are needed to produce eggs while in the latter, only one organism is needed. However, in most cases, an insect's life begins from an egg. An insect egg goes through a period of metamorphosis from where it transforms from a young to an adult insect.

Lastly, insects are considered to be animals because they eat organic matter. The eating behavior of an insect is determined by the environment. The range of foods is diverse and includes plants to small creatures. For example, parasites like fleas prey on the blood or skin of other large animals without killing them.


Insects Are The Only Animals With Six Legs

Yes, insects are the only animals that have six legs. Apart from the legs, the body of an insect includes an exoskeleton, two antennae, head, thorax, and abdomen.

When it comes to the animal kingdom, insects are the only ones that have six legs. Most insects will have wings that allow them to travel to different habitats. The six legs can be divided into three pairs of legs.

Each pair is linked with the segments of the thorax. They are classified as forelegs, mid legs, and hind legs. The insect's legs have been modified and evolved to assist the animal to move, escape prey, mate, feed, and so on.

Coxa, trochanter, femur, tibia and tarsus are the five basic segments of an insect's leg. These parts allow the insects to effortlessly run, jump, dig, grasp, catch, walk, and mate. Therefore, these animals have evolved these three pairs of legs to survive and thrive.

Here at Kidadl, we have carefully created lots of interesting family-friendly facts for everyone to enjoy! If you liked our suggestions for are insects animals? Then why not take a look at what do June bugs eat or Spiny Leaf Insect Facts?

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Written by Rajnandini Roychoudhury

Bachelor of Arts specializing in English, Master of Arts specializing in English

Rajnandini Roychoudhury picture

Rajnandini RoychoudhuryBachelor of Arts specializing in English, Master of Arts specializing in English

With a Master of Arts in English, Rajnandini has pursued her passion for the arts and has become an experienced content writer. She has worked with companies such as Writer's Zone and has had her writing skills recognized by publications such as The Telegraph. Rajnandini is also trilingual and enjoys various hobbies such as music, movies, travel, philanthropy, writing her blog, and reading classic British literature. 

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Fact-checked by Vikhaash Sundararaj

Bachelor of Fine Arts specializing in International Business

Vikhaash Sundararaj picture

Vikhaash SundararajBachelor of Fine Arts specializing in International Business

With a background in International Business Management, having completed his degree at the University of Hull. Vikhaash has volunteered with 'Teach For India' to help students create a monthly newsletter. In his free time, he enjoys sports and was the assistant captain of his school's hockey team. He has also gained marketing experience through an internship at Decathlon Sports India.

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