Porifera

PoriferaAshley MurrayHolly LoewenTara MoriartyKatelyn Nearing

Porifera are more commonly known as spongesApproximately 5000 living species classified under this taxon3 distinct groups: Hexactinellida (glass), Demospongia, and CalceraWhat are Porifera?

Hexa- glassCalcera- calcereous sponges2One of the oldest known animal fossils (pre-Cambrian)Greatest diversity during Cretaceous periodMajor contributors to reef formation during the Phanerozoic periodStill important constituents of reef communitiesEvolutionary Origin

Do not have mouths- tiny pores through which they absorb waterFlow of water through the sponge is unidirectionalVariety of coloursFound at any latitudeSessile, but some are able to move if attached to a crab shellEither asexual or sexualSkeleton made of collagen and spiculesCharacteristics

Flow governed by series of canals4Water provides food and oxygen and a means for waste removalVolume of water can exceed 20,000x the sponges volume in 24 hoursFilter bacteria from water (90% of bacteria found in water gets filtered out)Can also have green algae from which they draw nutrientsSome sponges are carnivorous- they eat crustaceansFeeding

Asexual and SexualMost are sexual (hermaphroditic)Produce eggs and sperm at different timesSperm is concentrated and released from excurrent opening (may be so dense that the sponge appears to be smoking!)Female sponges of the same species capture the sperm and fertilize the eggs through archaeocytes (special cells that transport sperm to the egg)Asexual sponges produce buds (gemmules- packets of several types of cells surrounded by a protective coating)Released into the water in the same manner as sexually-reproduced spongesReproduction

-Archaeocytes- special cells that transport the sperm to the egg for fertilization-Fertilization occurs in the mesenchyme, producing ciliated larvae which are released and settle into the water column, where they grow into juvenile sponges-Gemmules are packets of several various types of cells protected by a protective covering6

These are the canals that allow water flowThe final exit for the water is the oscularVolcano-shaped mounds, openings are as small as one millimeter7www.ucmp.berkley.edu/porifera/poriferalh.htmlwww.ucmp.berkley.edu/porifera/poriferamm.htmlhttp://animaldiversity.ummz.umich.edu/accounts/Porifera/http://tolweb.org/Porifera/2464http://paleo.cortland.edu/tutorial/Protista/porifera.htm http://www.ebiomedia.com/prod/BOsponges.htmlhttp://www.infusion.allconet.org/webquest/PhylumPorifera.html

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