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 Dragonflies
are very interesting insects. They have six legs
and three body parts: a head, a thorax, and an abdomen. They have four wings.
Their front wings can be going
up, while their back ones are
going down. They can even fly backwards! Also, they fly
very fast. Some dragonflies can fly at 58 kilometers per hour.
The dragonfly begins its life as an egg. Adult female dragonflies lay their eggs in the water.
After about two weeks, the eggs hatch. Baby dragonflies are
called nymphs. Dragonfly nymphs
live in the water for about a year. While underwater, they eat mosquito nymphs, tiny fish, and pollywogs. As they grow,
they molt. After leaving the water
and becoming flying insects, they only live only a few months. Their
natural predators are birds.
Dragonflies are ancient insects. They were
around before the dinosaurs. This means that dragonflies have
been around 300 million years! Ancient dragonflies may have been larger
than those we see today.
One prehistoric fossil had a wingspan of 20 centimeters!
It was found in a coal mine in England. The
largest known dragonfly had a wingspan of 60 centimeters. Today, the
largest dragonfly is found in Costa Rica. It has a wingspan of 18
centimeters. Other than being smaller, modern-day dragonflies do not
look very different from their ancestors.
So, are dragonflies helpful to humans? Yes, they are! As a matter of fact, dragonflies
are sometimes called "mosquito hawk." This is because
they catch and eat so many mosquitoes. |
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