Fun Facts About Roundworms

Roundworms, also called threadworms, share a long history with human beings. According to Albert O. Bush, the author of "Parasitism: The Diversity and Ecology of Animal Parasites," roundworm infections date back to 2,700 B.C., with references recovered from literature of ancient civilizations of the Orient and Middle East. Unlike popularly thought, however, not all species of roundworms are parasitic.

Oldest Reference

• According to Satendra Khera in the book "Ascaris, the Intestinal Roundworm," the Yellow Emperor's Classic of Internal Medicine, or Huang Ti Nei Ching (China ca. 2,700 B.C.), is the oldest reference to parasitic roundworms.

Size and Reproduction

• Most species of roundworms are microscopic. One species of roundworm, Placentonema gigantissima, which parasitizes the large sperm whale, can reach 13 meters, or nearly 512 inches in length.

  Roundworms reproduce sexually and some species can lay more than 200,000 eggs in a single day. Roundworms are either female, male or hermaphroditic---meaning they have both male and female sexual organs and can reproduce their own young. An example of a hermaphrodite is Caenorhabditis elegans, which is a soil-dwelling, non-parasitic roundworm.

Taste and Odor

• According to Tara Rodden Robinson in the book "Genetics for Dummies," roundworms can detect odors, have a sense of taste and react differently to changes in temperature and light.

Abundance

• According to Kimm Bellotto, Katie Kubesh and Niki McNeil in the book "Invertebrates," there are more than 500,000 species of roundworms around the world. They are found in various environments, including saltwater, freshwater and soil.

  According to George McKay, Fred Cooke and Jenni Bruce in the "The Encyclopedia of Animals: A Complete Visual Guide," roundworms are one of the most abundant species of all animals, and a single rotting apple was found to have more than 90,000 roundworms.

Usefulness

• Medical researchers commonly use roundworms to study a variety of human diseases, including muscular dystrophy and Alzheimer's disease. According to researchers from the University of Kansas, roundworms and humans have similar body organization and studies conducted on the worm can essentially be translated to human beings. According to Erik Lundquist, an associate professor at the University of Kansas, the Caenorhabditis elegans roundworm is a simple organism with only 959 cells. Its genetic code, however, is similar to that of humans and its genes perform the same functions as they do in humans. Researchers study how the genes work in the worm to gain more knowledge about their functioning and working in the human body.