Types of Earthworms
There are more than 2,700 types of earthworms in the world, with sizes ranging from few inches to 2 - 3 ft. They come in colors like purple, reddish brown, and bright blue. Red worms, night crawlers, gray worms, and tiger worms are some types of earthworms. Some of these species are also eaten by people and used as bait or enticement to catch fish.
World's Biggest Earthworm
The giant Gippsland earthworm found in Australia, is the biggest earthworm species in the world. On an average, they measure around 3.3 ft in length and have a diameter of 0.79 in. Their head is dark purple in color, while their body is bluish-gray.
They live in deep burrows in soil and need water for respiration. These earthworms have a comparatively longer lifespan and can take around 5 years to reach maturity. They breed during hotter months of the year and lay egg cocoons in their burrows. The newborns are around 7.9 in when they hatch after a period of 12 months.
How Many Hearts Does an Earthworm Have?
Earthworms do not have hearts, but have an organ known as the 'aortic arch' that carries out the functions of the heart. They have five aortic arches, and in between each, there is a gland that helps the worm digest calcium that is absorbed from eating dirt. Every 'aortic arch' functions in a similar way, so they cannot be differentiated.
They help to pump blood around the body, but don't have any chambers. Earthworms don't have lungs either. They breathe through their skin, taking in oxygen and releasing carbon dioxide.
Do Earthworms Have Eyes?
Earthworms don't have eyes, but are still able to sense light by their anterior. They can't bear light for a long time though, and are paralyzed if exposed to it for a long time. An earthworm will also die if its skin becomes dry.
What Do Earthworms Eat?
They primarily feed on decaying plants and other small organisms. They mostly obtain their food from the ground in which they burrow. They use large amounts of soil and small pebbles to extract the organic stuff that is needed as nutrition.
They store all nutrients in their gastric mill and deposit the waste material outside their burrow. According to a study, an earthworm takes in and pulverizes food equal to its own weight, every day.
They till the ground and create small tunnels that allow air and moisture to pass through, which, in turn, helps in plant growth.Tunnels store water that can be used by plants and allow the air to pass, which causes bacteria to break down organic matter within the soil.
How Do Earthworms Reproduce?
The reproductive system of earthworms is different from other insects and animals. They are hermaphrodites, meaning they have both male and female sex organs. An earthworm can produce sperms as well as eggs. However, it can only fertilize its eggs by the sperms of another earthworm. Hence, they need to find sexual partners and obtain sperms from each other.
Hereafter, if you get a chance to see an earthworm, just think about what all it can do.