About 75% of the world’s animals are insects. They have been living on earth for over 400 million years, long before humans appeared. Insects have changed a lot and adapted to new climates in order to survive. Today, there are about one million different species of insects and scientists are discovering new groups daily. Insects have different sizes and body forms. Most of them are very small but they can grow as large as 30 cm. Among the most common insects are flies,beetles, bees, butterflies, moths and wasps.
Where insects live
Insects live in every region of the world. They can survive in any type of climate, from tropical rainforests to icy polar regions, as long as they can find food. The oceans are the only places where few insects live. Because they are so small, they can live in places where other animals cannot survive, some even live in underground caves.
Physical features
Insects belong to a group of animals called arthropods. They do not have a skeleton but a kind of shell that protects them. This exoskeleton is very tight and does not grow with the insect. When an insect becomes too large for the shell it breaks open and a new shell develops.
Insects have three major body parts: head, thorax and abdomen. They have six legs and at least one pair of feelers.
An insect’s antennae, mouth and eyes are located in the head. The compound eyes consist of up to 4,000 separate lenses that combine images inside an insect’s brain. Such a complex eye gives it extremely good eyesight. Insects use antennae to smell and feel. If their feelers are damaged they become helpless.
The thorax has three pairs of legs and two pairs of wings, however, some insects have no wings at all.
The abdomen is the largest part of an insect. It contains organs that digest food, release waste and let insects reproduce.
How insects behave
Insects protect themselves from enemies in many ways. Some can blend into their surroundings by changing their colours. Others, like beetles, have a hard shell that protects them. Some insects produce poison and inject it into enemies by biting or stinging them.
Most insects live alone but there are some social insects that live in colonies.Termites, ants and bees are examples of insects that live in groups of thousands or even millions, in which everything is organized and each insect has a certaintask. Such a society is headed by a leader, a queen or a king, whom othersfollow.
Insects eat plants, animals and other organisms. They also live on other animals and get food from their body. Such insects are called parasites.
Certain insects migrate during the wintertime. The monarch butterfly, for example, flies south to tropical and subtropical areas. In spring they come back to their original habitat.
Life cycle of insects
Most insects are born from eggs. Their covering or shell cannot grow and they break out of it after a certain time. After that an insect grows a new shell. This process is called moulting. An insect can moult many times until it becomes a fully grown adult. This process, from hatching out of an egg to becoming an adult, can take between a few days and many years. As an adult, most insects live only for a short time. But there are a few, like the queen of a termite colony, which can live for many years.
Some insects change completely during the different stages of their life. This is called metamorphosis. After hatching from an egg they become a larva, which takes on a wormlike shape. A larva eats a lot and moults several times during its development process. After growth an insect becomes a pupa. It spins a protective covering around itself. During this resting stage an insect develops wings and legs and other body features. In the final stage an adult emerges from the pupa. Bees and butterflies grow in this way.
Insects and humans
Insects can be helpful to humans in many ways. They eat other insects and dangerous animals that may endanger fields and crops. They keep ourenvironment clean by eating animal waste and other unwanted substances. Some produce valuable products like honey and silk. Flowers, fruits and other plants depend on insects to help spread pollen. On the other side, insects are an important source of food for birds, frogs and other animals.
There are very few harmful types of insects, but they can do a lot of damage. Some of them spread diseases by stinging and biting people. In tropical regions insects are the main carriers of malaria or the plague. They injure pets and animals, and do damage to trees and crops.
About 75% of the world’s animals are insects. They have been living on earth for over 400 million years, long before humans appeared. Insects have changed a lot and adapted to new climates in order to survive. Today, there are about one million different species of insects and scientists are discovering new groups daily. Insects have different sizes and body forms. Most of them are very small but they can grow as large as 30 cm. Among the most common insects are flies,beetles, bees, butterflies, moths and wasps.
Where insects live
Insects live in every region of the world. They can survive in any type of climate, from tropical rainforests to icy polar regions, as long as they can find food. The oceans are the only places where few insects live. Because they are so small, they can live in places where other animals cannot survive, some even live in underground caves.
Physical features
Insects belong to a group of animals called arthropods. They do not have a skeleton but a kind of shell that protects them. This exoskeleton is very tight and does not grow with the insect. When an insect becomes too large for the shell it breaks open and a new shell develops.
Insects have three major body parts: head, thorax and abdomen. They have six legs and at least one pair of feelers.
An insect’s antennae, mouth and eyes are located in the head. The compound eyes consist of up to 4,000 separate lenses that combine images inside an insect’s brain. Such a complex eye gives it extremely good eyesight. Insects use antennae to smell and feel. If their feelers are damaged they become helpless.
The thorax has three pairs of legs and two pairs of wings, however, some insects have no wings at all.
The abdomen is the largest part of an insect. It contains organs that digest food, release waste and let insects reproduce.
How insects behave
Insects protect themselves from enemies in many ways. Some can blend into their surroundings by changing their colours. Others, like beetles, have a hard shell that protects them. Some insects produce poison and inject it into enemies by biting or stinging them.
Most insects live alone but there are some social insects that live in colonies.Termites, ants and bees are examples of insects that live in groups of thousands or even millions, in which everything is organized and each insect has a certaintask. Such a society is headed by a leader, a queen or a king, whom othersfollow.
Insects eat plants, animals and other organisms. They also live on other animals and get food from their body. Such insects are called parasites.
Certain insects migrate during the wintertime. The monarch butterfly, for example, flies south to tropical and subtropical areas. In spring they come back to their original habitat.
Life cycle of insects
Most insects are born from eggs. Their covering or shell cannot grow and they break out of it after a certain time. After that an insect grows a new shell. This process is called moulting. An insect can moult many times until it becomes a fully grown adult. This process, from hatching out of an egg to becoming an adult, can take between a few days and many years. As an adult, most insects live only for a short time. But there are a few, like the queen of a termite colony, which can live for many years.
Some insects change completely during the different stages of their life. This is called metamorphosis. After hatching from an egg they become a larva, which takes on a wormlike shape. A larva eats a lot and moults several times during its development process. After growth an insect becomes a pupa. It spins a protective covering around itself. During this resting stage an insect develops wings and legs and other body features. In the final stage an adult emerges from the pupa. Bees and butterflies grow in this way.
Insects and humans
Insects can be helpful to humans in many ways. They eat other insects and dangerous animals that may endanger fields and crops. They keep ourenvironment clean by eating animal waste and other unwanted substances. Some produce valuable products like honey and silk. Flowers, fruits and other plants depend on insects to help spread pollen. On the other side, insects are an important source of food for birds, frogs and other animals.
There are very few harmful types of insects, but they can do a lot of damage. Some of them spread diseases by stinging and biting people. In tropical regions insects are the main carriers of malaria or the plague. They injure pets and animals, and do damage to trees and crops.
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About 75% of the world’s animals are insects. They have been living on earth for over 400 million years, long before humans appeared. Insects have changed a lot and adapted to new climates in order to survive. Today, there are about one million different species of insects and scientists are discovering new groups daily. Insects have different sizes and body forms. Most of them are very small but they can grow as large as 30 cm. Among the most common insects are flies,beetles, bees, butterflies, moths and wasps.
Where insects live
Insects live in every region of the world. They can survive in any type of climate, from tropical rainforests to icy polar regions, as long as they can find food. The oceans are the only places where few insects live. Because they are so small, they can live in places where other animals cannot survive, some even live in underground caves.
Physical features
Insects belong to a group of animals called arthropods. They do not have a skeleton but a kind of shell that protects them. This exoskeleton is very tight and does not grow with the insect. When an insect becomes too large for the shell it breaks open and a new shell develops.
Insects have three major body parts: head, thorax and abdomen. They have six legs and at least one pair of feelers.
An insect’s antennae, mouth and eyes are located in the head. The compound eyes consist of up to 4,000 separate lenses that combine images inside an insect’s brain. Such a complex eye gives it extremely good eyesight. Insects use antennae to smell and feel. If their feelers are damaged they become helpless.
The thorax has three pairs of legs and two pairs of wings, however, some insects have no wings at all.
The abdomen is the largest part of an insect. It contains organs that digest food, release waste and let insects reproduce.
How insects behave
Insects protect themselves from enemies in many ways. Some can blend into their surroundings by changing their colours. Others, like beetles, have a hard shell that protects them. Some insects produce poison and inject it into enemies by biting or stinging them.
Most insects live alone but there are some social insects that live in colonies.Termites, ants and bees are examples of insects that live in groups of thousands or even millions, in which everything is organized and each insect has a certaintask. Such a society is headed by a leader, a queen or a king, whom othersfollow.
Insects eat plants, animals and other organisms. They also live on other animals and get food from their body. Such insects are called parasites.
Certain insects migrate during the wintertime. The monarch butterfly, for example, flies south to tropical and subtropical areas. In spring they come back to their original habitat.
Life cycle of insects
Most insects are born from eggs. Their covering or shell cannot grow and they break out of it after a certain time. After that an insect grows a new shell. This process is called moulting. An insect can moult many times until it becomes a fully grown adult. This process, from hatching out of an egg to becoming an adult, can take between a few days and many years. As an adult, most insects live only for a short time. But there are a few, like the queen of a termite colony, which can live for many years.
Some insects change completely during the different stages of their life. This is called metamorphosis. After hatching from an egg they become a larva, which takes on a wormlike shape. A larva eats a lot and moults several times during its development process. After growth an insect becomes a pupa. It spins a protective covering around itself. During this resting stage an insect develops wings and legs and other body features. In the final stage an adult emerges from the pupa. Bees and butterflies grow in this way.
Insects and humans
Insects can be helpful to humans in many ways. They eat other insects and dangerous animals that may endanger fields and crops. They keep ourenvironment clean by eating animal waste and other unwanted substances. Some produce valuable products like honey and silk. Flowers, fruits and other plants depend on insects to help spread pollen. On the other side, insects are an important source of food for birds, frogs and other animals.
There are very few harmful types of insects, but they can do a lot of damage. Some of them spread diseases by stinging and biting people. In tropical regions insects are the main carriers of malaria or the plague. They injure pets and animals, and do damage to trees and crops.
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