Earthworms (Phylum - Annelida, Class - Chaetopoda, Order - Oligochaeta) occupy a unique position in animal kingdom and are the first group of multi cellular and eucoelomate invertebrates who have succeeded to inhabit terrestrial environment. The knowledge about the importance of earthworms is not a very modern phenomenon. The Ancient Greeks regarded the earthworm to play an important role in improving the quality of the soil. The Greek philosopher Aristotle (384 – 322 B.C.) regarded worms as “the
commonly become seven to eight centimeters in length, and spend a lot of their time eating using their mouth which is located in the first segment of their body. ("National Geographic Common,") This first segment is the one located closest to the clitellum, which is the thick ring like band that demonstrates a worm is mature in growth. These worms move by taking full advantage of their small
ventrolateral surface, the body segments 8, 9, 10, 11 and 12 shows the presence of spermathecal openings. Exactly on the 12 segment, a pair of female genital openings is present. Segments 13, 14 and 15 forms the unsegmented collar like structure called the clitellum. On the 16 segment, pair of male genital openings is present, bellow the
released and fertilized in the open water by free floating sperm. After this stage they cling onto rock and begin their sessile, basic, life.... ... middle of paper ... ...d female reproductive organs. An egg becomes fertilized when they rub clitellum. Earthworms play an important part in the environment. They break down organic matter and dig tunnels under the soil that help increase water and oxygen flow. Throughout the various phyla discussed evolutionary advancements are relevant. Starting