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Earthworms are environmental indicators of soil health. Earthworms feed on the decaying matter in the soil and analyzing the contents of their digestive tracts gives insight into the overall condition of the soil. The earthworm gut accumulates chemicals, including heavy metals such as cadmium, mercury, zinc, and copper. The population size of ...
The worm has a hydrostatic skeleton and moves by longitudinal and circular muscular contractions. Setae – tiny hair-like projections – provide leverage against the surrounding soil. Surface movements on moist, flat terrain were reported at a speed of 20 m/h and, based on measurements of the length of the trail, nocturnal activity away from ...
Oligochaetes are well-segmented worms and most have a spacious body cavity (coelom) used as a hydroskeleton.They range in length from less than 0.5 mm (0.02 in) up to 2 to 3 metres (6.6 to 9.8 ft) in the 'giant' species such as the giant Gippsland earthworm (Megascolides australis) and the Mekong worm (Amynthas mekongianus).
Many animals with a wormlike cylindrical body have a hydrostatic skeleton with a flexible skin and a water-filled body cavity (coelom or pseudocoelom). They move by peristalsis, using opposed circular and longitudinal muscles, which act on the hydrostatic skeleton to change the body's shape. Hydrostatic skeletons are typically arranged in a ...
Original – Diagram of the head of an earthworm including most of its major organs Reason Meets all of the FP criteria for SVG diagrams, including being freely licensed Articles in which this image appears Earthworm, Lumbricus terrestris FP category for this image Wikipedia:Featured pictures/Sciences/Biology Creator KDS4444
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They are also often the numerically dominant earthworm species in England, especially in neutral to base-rich grasslands and arable soils. [9] Because Allolobophora chlorotica is an endogeic worm, it builds complex lateral burrow systems through all layers of the upper mineral soil. This species of worm rarely comes to the surface, instead it ...
Earthworms store their partners' sperm in spermathecae ("sperm stores") and then the clitellum produces a cocoon that collects ova from the ovaries and then sperm from the spermathecae. Fertilization and development of earthworm eggs takes place in the cocoon. Leeches' eggs are fertilized in the ovaries, and then transferred to the cocoon.