Porifera
Ashley Murray
Holly Loewen
Tara Moriarty
Katelyn Nearing
What are Porifera?
 Porifera are more commonly known as
sponges
 Approximately 5000 living species classified
under this taxon
 3 distinct groups: Hexactinellida (glass),
Demospongia, and Calcera
Evolutionary Origin
 One of the oldest known animal
fossils (pre-Cambrian)
 Greatest diversity during Cretaceous
period
 Major contributors to reef formation
during the Phanerozoic period
 Still important constituents of reef
communities
Characteristics
 Do not have mouths- tiny pores through which they
absorb water
 Flow of water through the sponge is unidirectional
 Variety of colours
 Found at any latitude
 Sessile, but some are able to move if attached to a
crab shell
 Either asexual or sexual
 Skeleton made of collagen and spicules
Feeding
 Water provides food and oxygen and a means for
waste removal
 Volume of water can exceed 20,000x the sponge’s
volume in 24 hours
 Filter bacteria from water (90% of bacteria found in
water gets filtered out)
 Can also have green algae from which they draw
nutrients
 Some sponges are carnivorous- they eat crustaceans
Reproduction
 Asexual and Sexual
 Most are sexual (hermaphroditic)
 Produce eggs and sperm at different times
 Sperm 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 sexuallyreproduced sponges
Sources
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www.ucmp.berkley.edu/porifera/poriferalh.html
www.ucmp.berkley.edu/porifera/poriferamm.html
http://animaldiversity.ummz.umich.edu/accounts/Porifera/
http://tolweb.org/Porifera/2464
http://paleo.cortland.edu/tutorial/Protista/porifera.htm
http://www.ebiomedia.com/prod/BOsponges.html
http://www.infusion.allconet.org/webquest/PhylumPorifer
a.html