The crawling invaders

Earthworms come to the surface during rains (especially in the Spring), so they can move over land. The temporarily wet conditions give worms a chance to move safely to new places. Since worms breathe through their skin, the skin must stay wet in order for the oxygen to pass through it. After rain or during high humidity are safe times for worms to move around without dehydrating. It is true that without oxygen worms will suffocate. But earthworms can survive for several weeks under water, providing there is sufficient oxygen in the water to support them. They surface as a response to high relative humidity after rain because they can move around safely without drying out.

The earthworm has many enemies, including mites, ants, centipedes, earwigs, nematodes, fly larvae, termites, springtails, sowbugs, snails, slugs, millipedes, spiders, birds, rats, mice, moles, gophers, toads and snakes.

Their bulky bodies are composed of three heavy body segments which are only supported by six long, thin legs. As they die they lose muscle control, causing the leg muscles to contract. As a result, the legs are pulled beneath the body, causing them to lose their balance and topple over onto their backs. This also explains why cockroaches on the wall fall off when they get sprayed with insecticides.

Lice are species-specific, which means there are different species of lice for each animal species that they depend on. Human lice need human blood to survive; dog lice need dog blood and so on. Therefore, if your child comes home from school with a diagnosis of head lice, your dog, cat or other pets in the household are not at risk of catching the lice or hatching eggs. Conversely, while lice are not common in dogs and cats, the species of lice that live on dogs and cats are not able to live on humans.

Worms do not have tongues. Certain worms do have something in their mouth that they can poke out, like a tongue. It is called a "stylet" and it looks like a needle.Worms that eat plants pierce the outside of the plant with their stylet. They then use the stylet like a straw to suck out food from inside the plant. But the worm's stylet isn't actually a tongue.

One job of our tongue is to crush food when we are eating it. Inside our tongue is a set of muscles. These muscles let our tongue move food around in our mouth, pushing it up against the hard palate at the top of our mouth. Worms need to crush up their food. But instead of using a tongue, worms have muscles in their gut that do this.

Another important job of our tongue is to taste food. Our tongue is covered in tiny bumps which contain taste buds. Worms have taste buds in special cells inside their mouth and other cells that are in their skin. As well as tasting, these cells also allow earthworms to smell. By sensing smells and tastes in the soil, worms can work out where they need to go to find food.