Illustration of the life cycle of the cicada, an insect found in temperate and tropical climates. At top right, the female lays eggs. When the eggs hatch, the newly hatched nymphs drop to the ground (lower right) and burrow into the soil (bottom). Most of the life cycle is spent underground, feeding on the sap from tree roots. The final nymphal instar burrows to the surface (lower left) and emerges above ground, moulting to produce the adult winged form (upper left). The life cycle is completed when a male and female cicada mate (top left). A typical cicada life cycle takes around 2-5 years. Cicadas make a loud buzzing noise similar to that of crickets. There are around 2500 species.