Invertebrate 15223 225903044 2008-07-15T23:02:23Z AndersBot 6986250 robot Adding: [[la:Invertebrata]] [[Image:Thelenota ananas.jpg|right|thumb|''Thelenota ananas'', a [[sea cucumber]] (phylum: [[Echinodermata]])]] An '''invertebrate''' is an [[animal]] lacking a [[vertebral column]]. The group includes 97% of all animal [[species]]<ref>[[Encarta]] Reference Library Premium 2005 DVD. Article - Invertebrate.</ref> — all animals except those in the [[Chordate]] [[subphylum]] [[vertebrate|Vertebrata]] ([[fish]], [[reptile]]s, [[amphibian]]s, [[bird]]s and [[mammal]]s). [[Carolus Linnaeus]]' ''[[Systema Naturae]]'' divided these animals into only two groups, the [[Insect]]a and the now-obsolete [[vermes]] ([[worm]]s). [[Jean-Baptiste Lamarck]], who was appointed to the position of "Curator of Insecta and Vermes" at the [[Muséum National d'Histoire Naturelle]] in 1793, both coined the term "invertebrate" to describe such and divided the original two groups into ten, by splitting off [[Arachnida]] and [[Crustacea]] from the Linnean Insecta, and [[Mollusca]], [[Annelida]], [[Cirripedia]], [[Radiata]], [[Coelenterata]] and [[Infusoria]] from the Linnean Vermes. They are now classified into over 30 [[phylum (biology)|phyla]], from simple organisms such as [[sea sponge]]s and [[flatworm]]s to complex animals such as [[arthropod]]s and [[Mollusca|molluscs]]. Invertebrates form a [[paraphyletic]] group. (For a full list of animals considered to be invertebrates, see [[animal]].) All the listed phyla are invertebrates along with two of the three [[subphylum|subphyla]] in Phylum [[chordate|Chordata]]: [[Tunicata|Urochordata]] and [[Lancelets|Cephalochordata]]. These two, plus all the other known invertebrates, have only one cluster of [[Homeobox|Hox genes]], while the vertebrates have duplicated their original cluster more than once. Within [[paleozoology]] and [[paleobiology]], invertebrates big and small are often studied within the [[fossil]] discipline called [[invertebrate paleontology]]. ==Phyla and common examples== [[Image:Calopteryx virgo male.jpg|right|thumb|''[[Beautiful Demoiselle|Calopteryx virgo]]'' (male), a [[damselfly]]]] [[Image:Cladocora.jpg|right|thumb|The fossil coral ''Cladocora'' from the [[Pliocene]] of [[Cyprus]].]] *[[Annelid]]a — [[segmented worm]]s ([[earthworm]]s, [[leech]]es, [[polychaete]]s) *[[Arthropod]]a — [[insect]]s, [[arachnid]]s, [[crustacean]]s *[[Cnidaria]] — [[jellyfish]]es, [[coral]]s, [[sea anemone]]s, [[Hydra (genus)|hydras]] *[[Echinoderm]]ata — [[starfish]], [[sea urchin]]s, [[sea cucumber]]s *[[Mollusca]] — [[squid]], [[snail]]s, [[bivalve]]s *[[Nematode|Nematoda]] — [[roundworm]]s *[[Nematomorpha]] — [[horsehair worm]]s or [[gordian worm]]s *[[Platyhelminthes]] — [[flatworm]]s *[[Porifera]] — [[sponge]]s ==Macroinvertebrates== The term '''macroinvertebrates''' is traditionally used to refer to aquatic invertebrates including [[insect]]s (e.g. larval [[Ephemeroptera]] and [[Trichoptera]]), [[crustacean]]s (e.g. [[amphipod]]s), [[mollusc]]s (e.g. aquatic [[snail]]s) and [[worm]]s (e.g. [[Platyhelminthe]]s), which inhabit a river channel, pond, lake, wetland or ocean. Historically, their abundance and diversity have been used as an indicator of ecosystem health and of local [[biodiversity]]. They are a key component of the [[food chain]]. Most indices that are used to determine water quality rank the various forms of [[benthic]] macroinvertebrates with respect to pollution sensitivity. The presence of pollution sensitive macroinvertebrates indicates that the body of water is healthy. Alternatively, the excessive presence of pollution tolerant macroinvertebrates indicates poor water quality. Ideally, a healthy body of water will hold an abundant and diverse macroinvertebrate population. The macroinvertebrates traditionally seen as being pollution sensitive include: [[Mayfly|mayflies]] (Ephemeroptera), [[Caddisfly|caddisflies]] (trichoptera), and [[Stonefly|stoneflies]] (Plecoptera). The macroinvertebrates that have been traditionally considered pollution tolerant include: aquatic worms (Oligocheata), leeches (Hirudinea) and non-biting midges or commonly known as "blood worms" (Chironomidae). [[Flow]], [[food]], [[habitat (ecology)|habitat]] and [[water quality]] are the primary determinants of macroinvertebrate abundance and diversity. Food sources include [[phytoplankton]], [[biofilm]]s (i.e. the layers of bacteria or other micro-organisms that cover submerged surfaces) and terrestrial organic material (e.g. leaves) that enter the water from the riparian vegetation. Major [[predation]] occurs from other macroinvertebrates and fish. Key habitats for macroinvertebrates are the benthic sediments, aquatic vegetation and woody debris. [[Salinity]], [[temperature]], [[dissolved oxygen]], and [[turbidity]] have a significant impact. There are many different kinds of arthropods. but they mainly have the structure of a segmented body and jointed legs. ==See also== * [[Marine invertebrates]] * Life Cycle of Macroinvertebrates http://www.lakecountyohio.org/soil/monitoring_information.htm Macroinvertebrates go through a life cycle in usually one season or less. They go through complete or incomplete metamorphosis. Learn more about the stages at this website. ==References== {{reflist}} ==Further reading== *[[Libbie Hyman|Hyman, L. H.]] 1940. ''The Invertebrates'' (6 volumes) New York : McGraw-Hill. A classic work. *Anderson, D. T. (Ed.). (2001). ''Invertebrate zoology'' (2nd ed.). Oxford: Oxford University Press. *Brusca, R. C., & Brusca, G. J. (2003). ''Invertebrates'' (2nd ed.). Sunderland, Mass. : Sinauer Associates. *Miller, S.A., & Harley, J.P. (1996). ''Zoology'' (4th ed.). Boston: WCB/McGraw-Hill. *{{cite book |title=Biology of the invertebrates |last=Pechenik |first=Jan A. |year=2005 |publisher=McGraw-Hill, Higher Education |location=Boston |isbn=0072348992 |pages=590 pp}} *Ruppert, E. E., Fox, R. S., & Barnes, R. D. (2004). ''Invertebrate zoology: a functional evolutionary approach''. Belmont, CA: Thomas-Brooks/Cole. ==External links== *{{cite book |author=A. R. Maggenti & S. Gardner |url=http://digitalcommons.unl.edu/onlinedictinvertzoology/ |title=Online Dictionary of Invertebrate Zoology |year=2005}} *[http://www.buglife.org.uk/News/Endangeredspeciessculpture.htm Support for endangered invertebrates] [[Category:Animals]] [[Category:Paleontology]] [[Category:Zoology]] [[ar:لافقاريات]] [[bs:Beskičmenjaci]] [[bg:Безгръбначни]] [[ca:Invertebrat]] [[cs:Bezobratlí]] [[cy:Infertebrat]] [[da:Hvirvelløse dyr]] [[de:Wirbellose]] [[et:Selgrootud]] [[es:Invertebrado]] [[eo:Senvertebruloj]] [[fa:بی‌مهرگان]] [[fr:Invertébré]] [[ko:무척추동물]] [[hr:Beskralješnjaci]] [[id:Invertebrata]] [[is:Hryggleysingjar]] [[it:Invertebrata]] [[he:חסרי חוליות]] [[ka:უხერხემლოები]] [[la:Invertebrata]] [[lt:Bestuburiai]] [[ln:Nyama ya mikúwa tɛ̂]] [[ms:Invertebrat]] [[nl:Ongewervelden]] [[ja:無脊椎動物]] [[no:Virvelløse dyr]] [[nn:Virvellause dyr]] [[nrm:Bête sans héthèque]] [[oc:Invertebrata]] [[pl:Bezkręgowce]] [[pt:Invertebrado]] [[ru:Беспозвоночные]] [[simple:Invertebrate]] [[sk:Bezstavovce]] [[sl:Nevretenčarji]] [[sr:Бескичмењаци]] [[fi:Selkärangattomat]] [[sv:Ryggradslösa djur]] [[tl:Invertebrata]] [[th:สัตว์ไม่มีกระดูกสันหลัง]] [[tr:Omurgasızlar]] [[uk:Безхребетні]] [[wa:Incronzoxhî]] [[zh:无脊椎动物]]