animal-life-cycles-chapter-2

CHAPTER TWO

Insects

Insects are small animals like butterflies, beetles, flies, bees, and ants. There are more than a million species of insect in the world. Many insects change in amazing ways during their life.

Larvae and Nymphs

Almost all insects start their life in an egg. The young insect grows inside the egg and then it hatches. Some baby insects, like bees, look very different from their parents. These baby insects are called larvae. Other baby insects, like locusts, look more like their parents. These baby insects are called nymphs. Larvae and nymphs are very small when they hatch.

Growing Up

A young insect eats a lot of food and grows very quickly. It has a hard cover, called an exoskeleton. When the exoskeleton is too small for the young insect, it breaks open and comes off. A new exoskeleton grows under the old one. This is called molting.

Some insects grow wings that get bigger every time they molt. After the insect molts for the last time, it becomes an adult that can fly and produce young. This is called incomplete metamorphosis.

Most insects change by complete metamorphosis. When the larva is ready to change into an adult, its exoskeleton comes off. Under the exoskeleton there’s a pupa — it’s like a closed case. Inside the pupa, an amazing change happens. The larva changes into an adult that looks completely different!

Finding a Mate

When insects become adults, they are ready to breed and produce young. First they need to find a mate. Male crickets, cicadas, and grasshoppers sing to find females that they can mate with.

Female butterflies and moths produce special chemicals called pheromones that have a strong smell. Male butterflies and moths can smell the pheromones from up to 2 kilometers away. They then fly toward the smell.

Male fireflies make special lights in their body. They turn these lights on and off so that female fireflies know that they are looking for a mate.

Laying Eggs

Some insects only lay a few eggs during their life, but others lay thousands. Many insects are careful to keep their eggs safe. The cardinal beetle makes a hole in dead wood and lays her eggs inside. When the eggs hatch, you can’t see the larvae very well. Cockroaches lay their eggs in a special case, and beetle eggs are usually yellow, green, or black so that they are camouflaged. When these insect eggs hatch, the life cycle starts again!

Termite queens lay up to 30,000 eggs every day!

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