In 1758, Swedish naturalist carolus linnaeus published descriptions of 654 species of beetle. Today, we know of 370,000 beetle species-and the number's still rising!
If an insects has just two wings it's sure to be a fly.In true flies, the back wings have become a pair of balancing knobs instead.These help flies to judge their speed and position in the air.
The biggest insecet the world ever seen were dragonfiles that lived in swamps about 300 million years ago.Fossils of these dragonflies show that they had wingspans of up to 75 cm (29.5in)