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Insects appeared on our planet at least 400 million years ago and evolved into different species of diverse sizes, forms and habits. Their small size might seem to be a disadvantage, but actually, the opposite true. It their very smallness that allows them to survive in the world. Their sheer number of at least a few million different species also ensures their survival.

Their life cycles also ensure their survival. Often different species change dramatically in form and lifestyles as they grow. For example, brightly coloured ugly caterpillars turn into butterflies. Mosquitoes begin as aquatic larvae. These changes allow insects food at different times of the year. Thus they can adapt to changes in their environment.

Few insects social but rather prefer to live a solitary life. In contrast, other insects such as ants and bees well known social insects. They live in colonies or hives, and their society very well organised, with each member having a particular function to perform. Workers or drones the job of building the nest as well as gathering food for the others. The soldier ants, for example, protect the nest and defend it against intruders. The queen ant or bee the job of laying eggs to propagate the community. They a living example of how effective teamwork can be.

Generally, most insects adopt a form having three parts, a head, thorax or chest, and an abdomen. Insects also six legs, and most equipped with antennae that used to sense their surroundings. The incredible thing about them their eyesight. Most compound eyes, which give them a field of vision of nearly 360°. That why it almost impossible to creep up on an insect. They also possess a very acute sense of smell as well as hearing. All these features help them to locate food or to find mates.

Insects form an essential part of the food chain. Fish, birds and small mammals depend on them as a food source. Their continued survival also guarantees the survival of other animal life, and they indeed indispensable to us.

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