Segmentation is common in all earthworms and consists of the longitudinal division of the body into repetitive units (segments) that give rise internally to compartments in the body cavity (coelom) separated by septa. Segmented animals typically have an anterior region - prostomium (or achron), a trunk and later a pigid (or telson).
Segmentation affects practically all aspects of the structure and functioning of animals, a fact quite evident in Annelids. One of its advantages relates to locomotion and comes, on the one hand, from the fact that the volume of the celómico fluid remains constant in each compartment, functioning as an antagonistic force against which the muscles can act and, on the other, from the possibility of independently control each segment. This allows the peristaltic movement (wave of contraction of the circular musculature followed by the contraction of longitudinal muscles) to be localized and involve only the strictly necessary muscles, considerably monetizing the energy needs of the movement.
Chemical nutrients and energy tend to flow in the same direction for most of an ecosystem. The big difference is that the chemical nutrients are ultimately recycled in the ecosystem while the energy is ultimately lost from the ecosystem to the universe at large. Energy in any ecosystem ultimately comes from the Sun
