Platyhelminthes

PlatyhelminthesKim Paul Emelie Poirier Chloe RaittHailey Reagh

IntroductionPlatyhelminthes Flatworms 20,000+ known species Range in length Feed on animal material, algae Bilaterally symmetrical 3 cell layers Mostly hermaphroditic Live everywhere Moist environments

EvolutionSoft, small bodies dont produce a well fossilized record.Schistosome larvae, oldest subspecies found, discovered in Egyptian Mummies.Nothing concrete found before them.Believed to have first appeared around 550 MYA.

very little known of their evolutionary history because they have very soft bodies which do not preserve well as fossils. Scientists believe first turbellarians evolved around 550 million years ago

3Biochemical aspects used to determine Tree of Life.Still discrepencies in Tree of Life with taxon relationships.Parasitic subgroup (Trematoda, Monogenea, and Cestoda) are believed to be monophyleticAcoela are believed to have a different ancestor.

Evolution

ClassificationPhylum PlatyhelminthesGreek wordsPlaty for flat Helminthes for wormClassesCestoda (parasitic tapeworms)Trematoda (parasitic flukes)Turbellaria (free living Planaria)

5Major Subgroups

TurbellariaFree-living groupMostly benthic and marineOver 4000 species

7TrematodaGroup of parasites9000 species have been discoveredWorm-like or flattened ovalHuman liver flukes and blood flukes

CestodaParasites5000 known speciesLong and flat bodies

CharacteristicsUnsegmented bodiesLack of skeletal systemLack of circulatory systemLack of body cavity Locomotion Nervous system Digestive system

11Fun Facts!Both salt water and freshwater

Tolerant of pollution

Come in great lengths

Withstand starvation

Simplest form of the worm

Regenerate

Reproduce sexually and asexually

Some interesting facts about the Platyhelminthes include their ability to be both a freshwater and marine organism. These organisms are extremely tolerant of pollution. They can grow to great lengths, some reaching the length of a school bus. Freshwater planarians can withstand extreme starvation having their body volume reduced to 1/300 of the original. The organism is the simplest form of the worm and are capable of reproducing sexually and asexually. 12ReferencesPlatyhelminthes. Gerlinger, Friedrich. Web. http://home.arcor.de/gerber.7/platyhelminthes.htm Flatworm Parasites. OShea, Lorraine. Web. http://poster.4teachers.org/view/poster.php?poster_id=379778 Ramel, Gordon (n.d). The Phylum Platyhelminthes. Earthlife. March 4, 2013, from http://www.earthlife.net/inverts/platyhelminthes.htmlTarget Informatics Pvt. Ltd. (2013). Platyhelminthes. Target Study. March 4, 2013, from http://targetstudy.com/nature/animals/platyhelminthes/http://www.ucmp.berkeley.edu/platyhelminthes/platyhelminthes.html http://www.naturwissenschaften.be/en/institute/associations/rbzs_website/bjz/back/pdf/BJZ%20131%28s1%29/Volume%20131%28s1%29,%20pp.%2035-46.pdfhttp://www.cisneros-heredia.org/infotrans/usfq/zoologia/pdfs/rohde2001.pdfCampbell, A. 2001. "Turbellaria" (On-line), Animal Diversity Web. Accessed March 06, 2013 at http://animaldiversity.ummz.umich.edu/accounts/Turbellaria/Myers, P. 2001. "Trematoda" (On-line), Animal Diversity Web. Accessed March 06, 2013 at http://animaldiversity.ummz.umich.edu/accounts/Trematoda/Myers, P. 2001. "Cestoda" (On-line), Animal Diversity Web. Accessed March 06, 2013 at http://animaldiversity.ummz.umich.edu/accounts/Cestoda/McDarby, Michael. (2001-2013). Flatworms(Platyhelminthes). An Online Introduction to the Biology of Animals and Plants. March 6, 2013, from http://faculty.fmcc.suny.edu/mcdarby/animals&plantsbook/animals/03-Flatworms.htm

Photos http://species.wikimedia.org/wiki/Platyhelmintheshttp://planet.uwc.ac.za/nisl/biodiversity/loe/page_20.htmhttp://quizlet.com/4357176/platyhelminthes-nematodes-rotifers-flash-cards/http://skepticalsquirrel.wordpress.com/2012/07/28/backwards-before-we-go-forwards/http://egy-king.blogspot.ca/2012/09/ancient-egyptian-mummies.htmlhttp://www.rzuser.uni-heidelberg.de/~bu6/Introduction11.htmlhttp://www.elasmodiver.com/images/flat-worm.jpghttp://sharonapbio-taxonomy.wikispaces.com/Animalia-Platyhelmintheshttp://www.richard-seaman.com/Underwater/Philippines/Nudibranchs/index.htmlhttp://www.starfish.ch/c-invertebrates/flatworms.htmlhttp://biodidac.bio.uottawa.ca/thumbnails/filedet.htm?File_name=Trem054p&File_type=gifhttp://eol.org/pages/2885/overviewhttp://www.rzuser.uni-heidelberg.de/~bu6/pow.htmlhttp://www.dscc.edu/bwilliams/biology%201120/biol_1120_lab_animals http://fineartamerica.com/featured/a-beautiful-flatworm-feeds-on-algae-terry-moore.html http://www.darwinsgalapagos.com/animals/platyhelminthes_flatworms.htmhttp://www.waterworxbali.com/flatworms.shtmlhttp://www.tranquil-seas.com/?_escaped_fragment_=portfolio