Earthworm at a Glance

By: Sydney Moore

Objective: Get familiar with the internal and external anatomy of an earthworm

Background

The scientific name of an earthworm is Lumbricus Terrestris. The earthworm is a very versatile animal that can live almost anywhere including marine, freshwater, and terrestrial habitats. An earthworm's diet consists of dead and decaying plant and animal matter. Although earthworms don't prey on very many animals, earthworms have many predators, including snakes, birds, rodents, and people. Earthworms play a very important role in their niche. They decompose dead plants and animals and are top-soil dweller, keeping their niche in order. The earthworm has many adaptions including no legs or antennae for burrowing, and the secretion of mucus and setae to help it move through the soil.

Digestive System Under a Microscope

The digestive system of an earthworm is very complex and essential to the life of the animal. The long process all starts at the mouth. The earthworm eats is food, usually soil and it travels down into the pharynx where it is swallowed. The food then travels down to the esophagus where is passes through calciferous glands that get rid of the excess calcium. The next stop of the journey is to the crop where the food is stored and then down to the gizzard where the food is completely grinded by previously digested stones. While gland cells release fluids that aid in the digestive process, the food moves to the intestine. The wall of the intestine contains blood vessels that transport and absorb the food. This system is essential in getting energy to every part of the earthworm's body and to the other systems.

The Method to the Earthworm's Madness

From Dirt to World

Earthworm Fun Facts

1. Earthworms contain both male and female body parts

2. The longest earthworm ever found was 22 feet long

3. There are 27,000 different types of worms

4. Worms are cold-blooded animals

5. Baby earthworms hatch from a cocoon

6. Worms don't have eyes, they sense the light

7. If a worm's skin dries out, it will die.

8. In one acre of land there can be more then one million worms

Up Close and Personal

1. Mouth

2. Pharynx

3. Seminal Receptacles

4. Seminal Vesicles

5. Crop

6. Gizzard

7. Intestine