The lithosphere; creatures living in the soil

Soil is home to many creatures. Some spend all their lives in it: earthworms, moles, mole-rats and many small invertebrates. Earthworms make tunnels; water and air enter through them, plant remains are broken up and the soil becomes fertile. They breathe through their skin, so in heavy rain, when the soil fills with water, they come up to the surface to breathe; that is why they are called “rain worms”. The mole is a small predator that eats insects, larvae and worms; its eyes are weak but its sense of smell and touch are sharp. The mole-rat feeds on plant roots and bulbs; it digs tunnels underground and loosens the soil, but farmers consider it a pest because it can damage crop roots. Some animals live in the soil temporarily: fox, badger, ground squirrel, mouse, snake and frog dig or use burrows to sleep or raise young. In the desert ground squirrels and tortoises also sleep through the scorching summer.