|MadSci Network: Zoology|
Hi Bernardin, When a Robin tries to pull an earthworm out of the ground, the worm uses these bristles to hold on tight to the wall of its home. Sometimes the worm holds on so tight and the Robin pulls so hard that the worm comes apart. The Robin keeps the front end and the hind end wriggles back into its burrow. If a bird pulls off the first 7 or 8 rings of the worm's body, new segments will grow. If a worm is pulled in half only the head end will grow back. Here is some more interesting information about earthworms. The earthworm has no lungs and takes in oxygen through its moist skin - it is a skin breather. If it dries out it will suffocate. Its skin is covered by mucus-secreting cells. The mucus serves not only in respiratory exchange, but it also lubricates the worm's body and eases passage through the burrow. The mucus covered skin helps bind soil particles together and prevents the walls of the burrow from collapsing. http://nysite.com/nature/fauna/earthworm.htm Dr. Cathy Fox has a great site that contains not only Technical Questions, but also, general information and everything "you wanted to know about worms". http://res.agr.ca/lond/pmrc/faq/earthwor.html If you would rather read a book on earthworms check out the following Earthworms, Dorothy Childs Hogner, 1953, Thomas Y. Crowell, New York Earthworms, John Mertus, 1993 Living Invertebrates, Editors Pearse and Buchsbaum, 1986, Boxwood Press, Pacific Grove, Ca. Hope this answers your question on earthworms. June Wingert Mad Scientist
Try the links in the MadSci Library for more information on Zoology.