Nightcrawler (Lumbricus Terrestris)
Nightcrawlers are a type of earthworm. Nightcrawlers can vary in color; some may be red, brown, or gray. Their bodies are covered with rings called annuli. Nightcrawlers dig into the ground and some can reach a depth of six feet! Mucus on the surface of the nightcrawler allows dissolved oxygen to pass through the bloodstream. Nightcrawlers can vary in size. For example, nightcrawlers in Europe can only reach a length of two inches while others in the United States can reach fourteen inches in length. Nightcrawlers are hermaphrodites. This means that they contain both male and female organs. The nightcrawler might have evolved in the sea or from the flatworm.
The nightcrawler has a closed circulatory system. Blood circulates through the blood vessels to various organs and other parts of its body. The blood also recirculates so it can reach maximum use. The worm uses its body to absorb oxygen from the soil. The oxygen is then transported through dorsal blood vessels. Blood, oxygen and other nutrients reach the esophagus by the lower ventral blood vessels.
The nightcrawler has a closed circulatory system. Blood circulates through the blood vessels to various organs and other parts of its body. The blood also recirculates so it can reach maximum use. The worm uses its body to absorb oxygen from the soil. The oxygen is then transported through dorsal blood vessels. Blood, oxygen and other nutrients reach the esophagus by the lower ventral blood vessels.