Physiology of Planarians
Clint Casey Planarians I. Diet: Planarians are carnivorous and eat other smaller animals. They also eat detritus, diatoms, dead animals, and decaying organic matter. (1) II. Predators: Larger carnivores eat planarians. Some fish such as the Crossocheilus siamensis (Siamese Algae Eater) have been studied to remove planarians from fish tanks. (3) III. Range: Most planarians live in fresh-water bodies. They also live in all oceans, and in moist terrestrial habitats. (5) IV. Microhabitat: Planarians are light-sensitive and during the day will be found under logs, rocks, or dead leaves. They can be found in springs, ditches, marshes, ponds, and lakes. (4) V. Reproduction: Planarians reproduce sexually and asexually. Asexually they can be pinched or cut in half and through regeneration, become two. Planarians are hermaphrodites and contain both eggs and sperm. (2) VI. Size: Planarians range in size from the 0.125- 1 inch. However, there are tropical terrestrial species that grow as large as 2 feet. (4) VII. Human Interest: Planarians are found in many experiments all over the world due to their amazing regenerating abilities. In particular, there were many famous experiments done in the 1960s by a biologist named John McConnell. He studied the effects of memory with planarians. (6) VIII. Works Cited: (1) Reece, Jane B., and Neil A. Campbell. Campbell Biology. Boston: Benjamin Cummings, 2011. 674-75. (2) http://people.westminstercollege.edu/faculty/tharrison/emigration/planaria.htm (3) http://en.wikipedia.org/wiki/Planarian (4) http://www.planarians.org/ (5) http://science.kennesaw.edu/~jdirnber/InvertZoo/LecPlatyhel/Platyhel.html (6)
Cited: (1) Reece, Jane B., and Neil A. Campbell. Campbell Biology. Boston: Benjamin Cummings, 2011. 674-75.
(2) http://people.westminstercollege.edu/faculty/tharrison/emigration/planaria.htm
(3) http://en.wikipedia.org/wiki/Planarian
(4) http://www.planarians.org/
(5) http://science.kennesaw.edu/~jdirnber/InvertZoo/LecPlatyhel/Platyhel.html
(6) http://archive.planet-science.com/outthere/lifemasks/mask.php?kingdom=animal&species=planaria