What are Insects?

Insects are the largest group of animals alive today.

Insects are a large and ancient group of animals. The oldest insect fossil is roughly 400 million years old and includes two different types of insects; a springtail Rhyniella praecursor and a true insect Rhyniognatha hirsti 1! To date, we have identified over 1 million insect species, but there may be upwards of 5.5 million insect species 2. So there may be 4.5 million insects we have yet to discover 2! Not only that, insects are found in almost all environments in the world including the hottest and coldest deserts.

There are many reasons insects are so successful in our world today: they have a mix of physical characteristics that work well together, they undergo metamorphosis, and they can reproduce quickly and successfully.

Insects have physical characteristics that work well together including: an exoskeleton, small size, and wings. The exoskeleton of an insect makes them tough, resistant to water loss, and acts as both a rigid and flexible skeleton for the insect. An insects small size means that the exoskeleton is not too heavy for the insect to get around, allows insects to consume and use small amounts of resources, and allows insects to utilize small spaces for shelter. Finally, most adult insects have wings which allows them to escape predators, move long distances, and forage effectively for many different types of food.

As many people know, insects undergo a process called metamorphosis that transforms immature insects into adult insects. One well known example of metamorphosis is the transofrmation of a butterfly. Butterflies start as an egg, hatch into a caterpillar, become a chrysalis, and then emerge from their chrysalis as an adult. Metamorphosis can change physical, biochemical, and behavioural characteristics of an insect which helps insects survive and thrive in most environments. One type of behaviour that changes when an insect develops is the type of food an insect stage consumes. For example, in butterflies larvae eat leaves and plant matter, which means adult butterflies can eat nectar without competing for food with their young.

Insects can reproduce quickly and successfully which allows them to have big populations and the ability to adapt quickly to new environments. Female insects can reproduce quickly by laying many eggs at once after mating with a single male or by producing offspring through asexual reproduction. For sexual reproduction, male insects produce enough sperm to mate with many females. This reproduction can produce many insects fast creating a large population in a short amount of time. Quick and successful reproduction (in combination with short life cycles) also allows insects to adapt quickly to environments or a changing environment. One example of this is that insects adapted very quickly to pesticides and some are now resistant to certain pesticides.

Out of all the insects, beetles are the most populous. There are about 400,000 described species of beetle. So, beetles make up 40% of all insects and 25% of all animal species. Beetles fulfill a variety of roles in ecosystems including pollination, acting as pests, and eating smaller pest insects.

The photo shows a golden ground beetle. these beetles are voracious predators and eat other insects.

"Golden Ground Beetle (Carabus auronitens auronitens) hibernating in dead wood" by berniedup is licensed under CC BY-SA 2.0

Insect anatomy allows us to recognize them easily.

Insects are uniquely adapted to their environment and lifestyle. This is why they can survive in so many places and why there are so many insects in the world. Despite insects being uniquely adapted to their environemnts, all insects have the same body parts and structure. Understanding the different parts of an insect's body (and what each part does) is essential to understanding and recognizing insects! An insect's body is divided into three main segments: the head, thorax, and abdomen.

The head contains the brain, eyes, antennae, and mouth appendages. The eyes of insects can be simple or compound. Simple eyes, also known as ocelli, are small and can only detect light. Compound eyes are large, made up of many facets, and can produce an image like our eyes! Insect antennae act like the insects nose. Insects use antennae to smell the air around them for important signals and to feel objects in their environment. Insects have many different types of appendages around their mouth and these can be used for chewing, lapping, piercing, sucking. Bees, for example, have appendages around their mouth for grabbing or cutting and appendages for lapping up nectar. The grabbing or cutting appendages are called mandibles and they use these to move and shape nesting material such as wax, dirt, and leaves. The lapping appendage allows bees to either lap or suck up flower nectar.

The thorax is the middle part of the insect's body. This is typically known as the locomotion segment as the legs and wings of adult insects are all attached to the thorax. All adult insects have six legs and these legs, like the mouthparts, can be shaped differently for different functions. Bumble bees, for example, have a structure called a pollen basket on the outside of their hind leg to carry pollen, and antenna cleaners on their front legs to clean their antenna. Most insects have wings and this is a key feature that made insects successful in colonizing most of the earth. Most insects have two pairs of wings and these vary greatly in size, shape, and function.

The abdomen is the last part of the insect's body, it contains the digestive, and reproductive organs. Many insects also have specialized structures on their abdomen like stingers used for defense.

"Scarab beetle = penseelkever" by e³°°° is licensed under CC BY-SA 2.0.

This photo shows a scarab beetle and each of the tagmata plainly. The first tagma, the head, is to the right and has a pair of antennae and compound eyes. The thorax, the middle tagma, is slightly hairy. This is where the wings and legs attach, but this is not readily apparent in this photo. Finally, the abdomen is the final segment on the left. The abdomen is covered by this beetle's spotted (and hardened) wing covers.

Why are insects important to humans?

Insects are essential to the preservation environments and ecosystems that are integral to human survival. They also play a significant role in our economy and culture. Even insects that may not seem beneficial, play important roles in the ecosystems they inhabit. Below you will find some of the benefits of having insects around!

Some insects are predators and predatory insects can help humans control pest populations. A good example of this is ladybugs that feed on aphids and other small insects 3. So, insects play a critical role in maintaining the balance of ecosystems by controlling the populations of other insects and small animals that might otherwise damage crops and other plants 4. When we use or apply insects in this way, it is known as biological pest control. By eating these pests, insects help to keep their populations in check and prevent them from causing significant damage to crops, gardens, and natural habitats.

Insects have significant economic importance for humans in both agricultural and non-agricultural industries. In agriculture, insects play a vital role as pollinators, helping to ensure the production of many of the fruits, vegetables, and nuts that make up a significant portion of the human diet. Bees, butterflies, flower flies, and even some wasps can be critical pollinators of many crops and other flowering plants 5. In addition to their role in agriculture, insects have significant economic importance for non-agricultural industries as well. Many insects are used in the production of food, medicine, and other products. For example, we use silkworms to make silk 6.

Insects have a large variety of impacts on our culture. Insects have been used in traditional medicine for centuries. Honey, for example, has been used for its antibacterial properties 7. Additionally, insects are consumed in many parts of the world including in Central America, South America, Africa, Asia, Australia, and New Zealand 8. Insects also have been used in many scientific fields, they have been used to study genetics, evolution, and disease, they are also commonly used as model organisms in laboratory experiments.

This flower has a beetle visitor! There are a variety of insects that act as pollinators. Most people know that bees are pollinators. Most people also know that butterflies also do some pollination. Butterflies don't have the same type of hair as bees to hold pollen, but do pollinate as they fly to different flowers to eat nectar.

Some of the more unknown insect pollinators include flies, wasps, beetles, and moths. All of these types of insects are attracted to flowers and provide pollination!

"Trillium ovatum with Pollinator" by brewbooks is licensed under CC BY-SA 2.0.

How do we conserve insects?

Conservation of insects is an important aspect of preserving biodiversity and maintaining the health of ecosystems. Insects are a vital part of many food webs, serving as pollinators, decomposers, and food for other animals. Their loss can have cascading effects on entire ecosystems, leading to declines in plant and animal populations, as well as the loss of ecosystem services such as pollination and pest control. Conservation efforts for insects can take many forms including habitat protection and restoration of insect habitats, monitoring and researching insects, and by educating people on insects and their importance.

One of the key strategies for conserving insects is the protection of their habitats, this can be done by creating protected areas such as national parks, nature reserves, and wildlife refuges, or by implementing conservation programs on private lands. Another way to protect insect habitat is to promote sustainable land use practices, such as organic farming and conservation tillage, that reduce the need for pesticides and protect natural habitats.

One important process to help conserve insects is the monitoring and research of their populations. This includes the collection of data on their distribution, abundance, and population trends, as well as research into their biology, ecology, and conservation needs. This information can be used to identify and prioritize conservation actions, as well as to track progress over time.

Finally, public awareness and education on the importance of insects is crucial for conserving insects. By reading about bees and insects, I hope you foster a love for these tiny creatures and tell people about them. Any and all awareness about the variety of bees, where they live, and how to help them out will lead to a better understanding of all insects. Every little bit helps.

Conservation of insects is crucial for the health of ecosystems and a loss of insects would be disasterous for humans and all other organisms that rely on them. It's important to remember that insects are not just pests, they are important and fascinating creatures that play a vital role in the functioning of the planet, and it's our responsibility to protect them.

Page information

Author: Melissa Platsko

Date published: April 3, 2022

Date last editied: July 31, 2023

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