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  • the enigmatic Ediacaran biota (fossil pictured) have been classified into every major group of lifeforms, including their own kingdom?

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Life Domain Kingdom Phylum Class Order Family Genus Species

The hierarchy of biological classification's eight major taxonomic ranks. .A kingdom contains one or more phyla.^ Most animal phyla are invertebrates (in fact, all animal phyla but one contain nothing but invertebrates) .

^ More than 40 different phyla are now recognized for the domain Bacteria , about half of which contain cultured representatives.
  • Discovery of the Novel Candidate Phylum “Poribacteria” in Marine Sponges 1 February 2010 3:40 UTC www.ncbi.nlm.nih.gov [Source type: Academic]

^ There are more than one million species of animals in at least 30 phyla, more species than all the other kingdoms combined.

Intermediate minor rankings are not shown.
.In biology, a phylum (plural: phyla)[note 1] is a taxonomic rank below Kingdom and above Class.^ Now technology has progressed and other scientists have developed the six-kingdom model (as seen below) which is currently being published in new biology textbooks.

^ In cases like that above, the lack attribution of phylum rank for these 'sponges' hides the fact that the Porifera may very well have given rise to an independent phyla.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ Much of the problem with “phylum”, as with other taxonomic ranks, is that whether or not you wish to create a taxonomic rank for a recognizable clade is arbitrary.
  • Down with phyla! - The Panda's Thumb 15 September 2009 2:02 UTC pandasthumb.org [Source type: Original source]

."Phylum" is equivalent to the botanical term division.^ "Phylum" is equivalent to the botanical term division .
  • Phylum - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: Reference]
  • Phylum - Fossil Wiki, the paleontology wiki 1 February 2010 3:40 UTC fossil.wikia.com [Source type: Academic]

^ "Phylum" is equivalent to the botanical term division.
  • Phylum - MSN Encarta 15 September 2009 2:02 UTC encarta.msn.com [Source type: General]
  • Phylum - ninemsn Encarta 15 September 2009 2:02 UTC au.encarta.msn.com [Source type: FILTERED WITH BAYES]

^ Phylum " is equivalent to the botanical term division.

[1]
.Although "phylum" is often used as if it were a clearly defined term, no satisfactory definition of it exists.^ Although the International Code of Botanical Nomenclature allows the use of the term "Phylum" in reference to plants , the term " Division " is almost always used by botanists.
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

^ In the Animal Kingdom, the term phylum is used, and it is the second largest group.
  • 95.05.08: The Animal Kingdom 1 February 2010 3:40 UTC www.yale.edu [Source type: FILTERED WITH BAYES]

^ Anti-evolutionists say they don't exist but they often don't define what it is that doesn't exist.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

.In fact, "phylum" may be a misnomer indicative of ignorance.^ In cases like that above, the lack attribution of phylum rank for these 'sponges' hides the fact that the Porifera may very well have given rise to an independent phyla.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

[2] .Consequently the number of phyla varies from one author to the next.^ H can vary from a very small number to almost one.
  • Introduction to Evolutionary Biology 15 September 2009 2:02 UTC www.talkorigins.org [Source type: FILTERED WITH BAYES]

.The relationships among phyla are becoming increasingly well known, and larger clades can be found to contain many of the phyla.^ The traditional separation in 'errant' and 'sedentary' polychaetes has increasingly become recognized as being unsatisfactory; however, the current trend towards grouping the polychaetes in many orders without specifying the relationships among the orders, is no more satisfactory.
  • Phylogeny of the Annelida and allies 1 February 2010 3:40 UTC www.annelida.net [Source type: Academic]

^ Members of this clade are characterized by obligate anaerobic growth and are found in the rumen and hindgut of many larger mammalian herbivores.
  • A molecular phylogeny of the flagellated fungi (Chytridiomycota) and description of a new phylum (Blastocladiomycota) -- James et al. 98 (6): 860 -- Mycologia 1 February 2010 3:40 UTC www.mycologia.org [Source type: Academic]

Contents

General description and familiar examples

.Informally, phyla can be thought of as grouping organisms based on general body plan,[3] as well as developmental or internal organizations.^ Informally, phyla can be thought of as grouping animals based on general body plan [1] , e.g., having bones vs. This is morphological grouping.
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

^ Informally, phyla can be thought of as grouping animals based on general body plan ; [1] this is morphological grouping.
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

^ "Phyla" is adopted from the Greek phylai , the clan-based voting groups in Greek city-states.
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

[4] .For example, though seemingly divergent, spiders and crabs both belong to Arthropoda, whereas earthworms and tapeworms, similar in shape, are from Annelida and Platyhelminthes, respectively.^ For example, though seemingly divergent, spiders and crabs both belong to Arthropoda , whereas earthworms and tapeworms , similar in shape, are from Annelida and Platyhelminthes , respectively.
  • Phylum - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: Reference]
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

^ The best known animal phyla are the Mollusca , Porifera , Cnidaria , Platyhelminthes , Nematoda , Annelida , Arthropoda , Echinodermata , and Chordata , the phylum to which humans belong.
  • Phylum - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: Reference]
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

.Although the International Code of Botanical Nomenclature allows the use of the term "phylum" in reference to plants, the term "Division" is almost always used by botanists.^ Although the International Code of Botanical Nomenclature allows the use of the term "Phylum" in reference to plants , the term " Division " is almost always used by botanists.
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

^ (Please, recall that botanists tend to use the taxonomic level "Division" for what zologists call "Phylum".
  • phylum ANNELIDA 1 February 2010 3:40 UTC inside.msj.edu [Source type: Academic]
  • phylum PORIFERA 1 February 2010 3:40 UTC inside.msj.edu [Source type: Academic]

^ In the Animal Kingdom, the term phylum is used, and it is the second largest group.
  • 95.05.08: The Animal Kingdom 1 February 2010 3:40 UTC www.yale.edu [Source type: FILTERED WITH BAYES]

.The best known animal phyla are the Mollusca, Porifera, Cnidaria, Platyhelminthes, Nematoda, Annelida, Arthropoda, Echinodermata, and Chordata, the phylum to which humans belong, along with all other vertebrate species, as well as some invertebrates such as the lamprey.^ There are three different phyla of worms, the Platyhelminthes, Annelida, and Nematoda.
  • 95.05.08: The Animal Kingdom 1 February 2010 3:40 UTC www.yale.edu [Source type: FILTERED WITH BAYES]

^ The phylum Porifera contain animals with pores all over their bodies known as sponges.
  • 95.05.08: The Animal Kingdom 1 February 2010 3:40 UTC www.yale.edu [Source type: FILTERED WITH BAYES]

^ The animals in this particular phylum are known as mollusks.
  • 95.05.08: The Animal Kingdom 1 February 2010 3:40 UTC www.yale.edu [Source type: FILTERED WITH BAYES]

.Although there are approximately 35 phyla, these nine include over 96% of animal species.^ Although there are approximately 35 phyla, these nine include over 96% of animal species.

^ Although there are approximately 35 phyla, these nine include the majority of the species.
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

^ These constitute the animal phyla.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

.Many phyla are exclusively marine, and only one phylum, the Onychophora (velvet worms) is entirely absent from the world's oceans–although ancestral onycophorans were marine.^ Many phyla are exclusively marine, and only one phylum is entirely absent from the world's oceans: the Onychophora or velvet worms.
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

^ Since just prior to the Vendian the only evidence for macroscopic life was that of the worms, if the various phyla were to evolve, it must have been from the worms.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ This phylum consists of earthworms, leeches, and various marine worms given many different names (e.g., sand worms, tube worms).
  • General Biology/Classification of Living Things/Eukaryotes/Animals/Phyla - Wikibooks, collection of open-content textbooks 1 February 2010 3:40 UTC en.wikibooks.org [Source type: FILTERED WITH BAYES]

[5]

Earliest known phyla

.The origin of phyla has traditionally been interpreted as a sudden and rapid event early in the Cambrian period, known as the Cambrian explosion.^ The change of environment caused by this event may have played a role in the Cambrian explosion.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ Culver argues that this fact is inconsistent with the above explanations of the Cambrian explosion and is only consistent with predation as a cause of the sudden skeletalization of major parts of the biosphere.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ No new phyla have appeared since that time (the Bryazoa [sicgrm] are one possible exception, but many paleontologists believe they will eventually be found to originate in the Cambrian period)."
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

[6] .However, this interpretation stemmed from an incomplete knowledge of the fossil record, and a circular definition of a phylum; organisms of the time were mainly similar to, but not strictly members of, modern phyla.^ However, this interpretation stemmed from an incomplete knowledge of the fossil record, and a circular definition of a phylum; organisms of the time were mainly similar to, but not strictly members of, modern phyla.

^ The magnitude of the event was also overestimated as early authors felt it necessary to erect a new phylum for any organism that could not be accommodated in modern phyla.

^ The significance of this event depends on (1) for how long modern phyla had existed prior to the Cambrian– fossil embryos and new interpretations of the Ediacara biota suggest that there may be a fair Precambrian root to the phyla; and (2) how soon phyla appeared in the Cambrian, a factor that depends on both the definition of a phylum and our interpretation of early fossils which may not display vital characteristics–for instance, non-mineralised parts of organisms rarely preserve.

[7] The significance of this event depends on two factors:
.
  1. How long did modern phyla exist prior to the Cambrian fossil embryos?^ Based upon this definition, which some say is unreasonably affected by the chance survival of rare groups, which vastly increase the size of phyla, representatives of many modern phyla did not appear until long after the Cambrian–as late as the Carboniferous in the case of the Priapulids.

    ^ The significance of this event depends on (1) for how long modern phyla had existed prior to the Cambrian– fossil embryos and new interpretations of the Ediacara biota suggest that there may be a fair Precambrian root to the phyla; and (2) how soon phyla appeared in the Cambrian, a factor that depends on both the definition of a phylum and our interpretation of early fossils which may not display vital characteristics–for instance, non-mineralised parts of organisms rarely preserve.

    ^ While one can assume that the 13 phyla which have no fossil record arose in the Cambrian, assumptions are NOT data.
    • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

    .New interpretations of the pre-Cambrian Ediacara biota suggest that there could have been an origin for some phyla earlier than the Cambrian.
  2. How soon did phyla appear in the Cambrian?^ So why did so many phyla suddenly appear in Cambrian Seas?
    • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

    ^ All the phyla (the second highest taxonomic category) of animals appeared around the Cambrian.
    • Introduction to Evolutionary Biology 15 September 2009 2:02 UTC www.talkorigins.org [Source type: FILTERED WITH BAYES]

    ^ Secondly, I will show that it is absolutely false that the majority of animal phyla appeared in the Cambrian.
    • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

    .This factor depends on both the definition of a phylum and on interpretation of early fossils, which may not display characteristics needed to determine membership in a modern phylum – non-mineralised parts of organisms are rarely preserved.^ Definitions of the prokaryote depending on absence of membrane-bounded organelles may require further reexamination, a process already underway [ 41 - 43 ].
    • BioMed Central | Full text | Phylum Verrucomicrobia representatives share a compartmentalized cell plan with members of bacterial phylum Planctomycetes 1 February 2010 3:40 UTC www.biomedcentral.com [Source type: Academic]

    ^ Some factors may increase the likelihood of the future risk of dangerousness, as determined by available research, but otherwise do not definitively establish a person’s imminent dangerousness."
    • Top 5 Sci-Fi Cliches That Need to Die from 1UP.com 1 February 2010 3:40 UTC www.1up.com [Source type: General]

    ^ Skeletalized organisms, including Cambrian-aspect shelly fossils, first appear below the boundary and then show strong diversification during the Early Cambrian.
    • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

    [8]
.The magnitude of the event was also overestimated as early authors felt it necessary to erect a new phylum for any organism that could not be accommodated in modern phyla.^ The magnitude of the event was also overestimated as early authors felt it necessary to erect a new phylum for any organism that could not be accommodated in modern phyla.

^ The significance of this event depends on (1) for how long modern phyla had existed prior to the Cambrian– fossil embryos and new interpretations of the Ediacara biota suggest that there may be a fair Precambrian root to the phyla; and (2) how soon phyla appeared in the Cambrian, a factor that depends on both the definition of a phylum and our interpretation of early fossils which may not display vital characteristics–for instance, non-mineralised parts of organisms rarely preserve.

^ There are around 35 different phyla (a number subject to change as new research makes rearrangements of the phylogenetic tree necessary).

.This approach is misleading and unhelpful; by one definition, such organisms do not fall into any phylum, but are classified as "aunts" of a phylum.^ Definition: The term phylum is one of seven major categories that are used to classify organisms.

^ This approach is misleading and unhelpful; by one definition, such organisms do not fall into any phylum, but are classified as "aunts" of a phylum.

^ What phylum does rust fall into?
  • What is the phylum for rust? | Smart QandA: Answers and facts you can trust, verified with Encyclopedia.com 1 February 2010 3:40 UTC qanda.encyclopedia.com [Source type: Academic]

[7]

Defining a phylum

.At the most basic level, a phylum can be defined in two ways: as a group of organisms with a certain degree of morphological or developmental similarity (the phenetic definition), or a group of organisms with a certain degree of evolutionary relatedness (the phylogenetic definition).^ Let's start with the most basic of definitions.
  • Top 5 Sci-Fi Cliches That Need to Die from 1UP.com 1 February 2010 3:40 UTC www.1up.com [Source type: General]

^ This group is a heterogenous assemblage of five strains that is not well supported as a clade but possesses some morphological similarities.
  • A molecular phylogeny of the flagellated fungi (Chytridiomycota) and description of a new phylum (Blastocladiomycota) -- James et al. 98 (6): 860 -- Mycologia 1 February 2010 3:40 UTC www.mycologia.org [Source type: Academic]

^ If two organisms share a similar anatomy, one would then predict that their gene sequences would be more similar than a morphologically distinct organism.
  • Introduction to Evolutionary Biology 15 September 2009 2:02 UTC www.talkorigins.org [Source type: FILTERED WITH BAYES]

[7] .Attempting to define a level of the Linnean hierarchy without referring to (evolutionary) relatedness is an unsatisfactory approach, but the phenetic definition is more useful when addressing questions of a morphological nature – such as how successful different body plans were.^ Attempting to define a level of the Linnean hierarchy without referring to relatedness is an unsatisfactory approach, but the phenetic definition is more useful when addressing questions of a morphological nature–such as how successful different body plans were.

^ So as to provide a handle on the size and significance of groups, a "body-plan" based definition of a phylum has been proposed by paleontologists Graham Budd an Sören Jensen.

^ At the most basic level, a phylum can be defined in two ways: as a group of organisms with a certain degree of morphological or developmental similarity (the phenetic definition), or a group of organisms with a certain degree of relatedness (the phylogenetic definition).

Definition based on genetic relation

.The largest objective measure in the above definitions is the "certain degree" – how unrelated do organisms need to be to be members of different phyla?^ Thus despite the seemingly different external appearances of organisms, they are classified into phyla based on their internal organizations.
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

.The minimal requirement is that all organisms in a phylum should be related closely enough for them to be clearly more closely related to one another than to any other group.^ Not closely related to other chelicerates .
  • Phylum Arthropoda 1 February 2010 3:40 UTC www.auburn.edu [Source type: Reference]

^ Slime molds are not closely related to other groups of plants or animals.

^ The turbellarian group is what needs to be sorted; sequence analysis indicates: 1) some turbellarians are not platyhelminths; and 2) some are platyhelminths but that they are more closely related to the other platyhelminth classes.
  • Chapter 12 - Phylum Mesozoa, Monoblastozoa, Porifera (tissue level) 1 February 2010 3:40 UTC www.austincc.edu [Source type: FILTERED WITH BAYES]

[7] .However, even this is problematic, as the requirement depends on our current knowledge about organisms' relationships: As more data becomes available, particularly from molecular studies, we are better able to judge the relationships between groups.^ The traditional separation in 'errant' and 'sedentary' polychaetes has increasingly become recognized as being unsatisfactory; however, the current trend towards grouping the polychaetes in many orders without specifying the relationships among the orders, is no more satisfactory.
  • Phylogeny of the Annelida and allies 1 February 2010 3:40 UTC www.annelida.net [Source type: Academic]

^ Wholesale revision of the systematics of Annelida or of groups therein awaits the availability of more comprehensive work.
  • Phylogeny of the Annelida and allies 1 February 2010 3:40 UTC www.annelida.net [Source type: Academic]

^ It will undoubtedly be heavily modified as genetic studies of relationships between these animals are published.
  • Phylum Ctenophora: list of all valid scientific names 15 September 2009 2:02 UTC faculty.washington.edu [Source type: FILTERED WITH BAYES]

.So phyla can be merged or split if it becomes apparent that they are related to one another or not; for example, since the onychophora and the tardigrada have now been accepted as stem groups of the arthropods, these three phyla should be combined.^ Before Linnaeus, long many-worded names had been used, sometimes with one additional adjective, sometimes with another, so that no true names were fixed and accepted.
  • Phylum (biology) - Discussion and Encyclopedia Article. Who is Phylum (biology)? What is Phylum (biology)? Where is Phylum (biology)? Definition of Phylum (biology). Meaning of Phylum (biology). 1 February 2010 3:40 UTC www.knowledgerush.com [Source type: FILTERED WITH BAYES]

^ The turbellarian group is what needs to be sorted; sequence analysis indicates: 1) some turbellarians are not platyhelminths; and 2) some are platyhelminths but that they are more closely related to the other platyhelminth classes.
  • Chapter 12 - Phylum Mesozoa, Monoblastozoa, Porifera (tissue level) 1 February 2010 3:40 UTC www.austincc.edu [Source type: FILTERED WITH BAYES]

^ The cephalopods are an ancient and very successful group, some of which are now the most advanced of all the invertebrates.  They have long been among the dominant large predators in our oceans.

.This changeability of phyla has led some biologists to call for the concept of a phylum to be abandoned in favour of cladistics, a method in groups are placed on a "family tree" without any formal ranking of group size.^ This has led to calls for the concept of a phylum to be abandoned in favour of cladistics, a method in groups are placed on a "family tree" without any formal ranking of group size.

^ Groups formerly ranked as phyla .
  • Phylum - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: Reference]
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]
  • Phylum (biology) - Paleontology Wiki 1 February 2010 3:40 UTC paleontology.wikia.com [Source type: FILTERED WITH BAYES]

^ So as to provide a handle on the size and significance of groups, a "body-plan" based definition of a phylum has been proposed by paleontologists Graham Budd an Sören Jensen.

[7] .So as to provide a handle on the size and significance of groups, a "body-plan" based definition of a phylum has been proposed by paleontologists Graham Budd and Sören Jensen.^ A phylum is a group of animals sharing a similar body plan.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ Jones (1985) argued that the vestimentiferan body plan was sufficiently distinct to warrant placement in a unique phylum, the Vestimentifera.
  • Phylogeny of the Annelida and allies 1 February 2010 3:40 UTC www.annelida.net [Source type: Academic]

^ See Figure 32.4, A traditional view of animal diversity based on body-plan grades ( for an overview of invertebrate relationships and characteristics) .

.The definition was posited by paleontologists because it is extinct organisms that are typically hardest to classify, because they can be extinct off-shoots that diverged from a phylum's history before the characters that define the modern phylum were all acquired.^ The definition was posited by paleontologists because it is extinct organisms that are typically hardest to classify, because they can be extinct off-shoots that diverged from a phylum's history before the characters that define the modern phylum were all acquired.

^ The magnitude of the event was also overestimated as early authors felt it necessary to erect a new phylum for any organism that could not be accommodated in modern phyla.

^ This design is shared by all members of the phylum, even though structural details may differ greatly because of evolution .
  • Phylum - MSN Encarta 15 September 2009 2:02 UTC encarta.msn.com [Source type: General]

Definition based on body plan

.By Budd and Jensen's definition, phyla are defined by a set of characters shared by all their living representatives.^ By Budd and Jensen's definition, phyla are defined by a set of characters shared by all their living representatives.

^ The definition was posited by paleontologists because it is extinct organisms that are typically hardest to classify, because they can be extinct off-shoots that diverged from a phylum's history before the characters that define the modern phylum were all acquired.

^ So as to provide a handle on the size and significance of groups, a "body-plan" based definition of a phylum has been proposed by paleontologists Graham Budd an Sören Jensen.

.This has a couple of small problems – for instance, characters common to most members of a phylum may be secondarily lost by some members.^ This has a couple of small problems – for instance, characters common to most members of a phylum may be secondarily lost by some members.

^ Nemotodes are the most common phylum, but not the most numerous.
  • Phylum Arthropoda is the largest phylum of invertebrates?? - Yahoo! Answers 1 February 2010 3:40 UTC answers.yahoo.com [Source type: General]

^ This design is shared by all members of the phylum, even though structural details may differ greatly because of evolution .
  • Phylum - MSN Encarta 15 September 2009 2:02 UTC encarta.msn.com [Source type: General]

.It is also defined based on an arbitrary point of time (the present).^ It is also defined based on an arbitrary point of time (the present).

.However, as it is character based, it is easy to apply to the fossil record.^ However, as it is character based, it is easy to apply to the fossil record.

^ However, proving that a fossil belongs to the crown group of a phylum is difficult, as it must display a character unique to a sub-set of the crown group.

^ However, this interpretation stemmed from an incomplete knowledge of the fossil record, and a circular definition of a phylum; organisms of the time were mainly similar to, but not strictly members of, modern phyla.

.A more major problem is that it relies on an objective decision of which group of organisms should be considered a phylum.^ A more major problem is that it relies on an objective decision of which group of organisms should be considered a phylum.

^ We clarify the relationship of C. elegans to major parasitic groups; this will allow more effective exploitation of our genetic and biological knowledge of this model species.
  • Citation: A molecular evolutionary framework for the phylum Nematoda 1 February 2010 3:40 UTC www.wormbase.org [Source type: Academic]

^ To simplify matters and to make the problem more manageable, scientists typically concentrate their attention on one organism which has characteristics which make it indicative of the overall health of the estuary.
  • Phylum Chordata 1 February 2010 3:40 UTC estuary.uconn.edu [Source type: FILTERED WITH BAYES]

.Its utility is that it makes it easy to classify extinct organisms as "stem groups" to the phyla with which they bear the most resemblance, based only on the taxonomically important similarities.^ Its utility is that it makes it easy to classify extinct organisms as "stem groups" to the phyla with which they bear the most resemblance, based only on the taxonomically important similarities.

^ The earlier classifications were based on morphological and developmental similarities; and individuals resembling each other were grouped together as a species, similar species as genera and so on.

^ From the first dawn of life, all organic beings are found to resemble each other in descending degrees, so they can be classed in groups under groups.
  • Phylum Chordata Tree of Life 1 February 2010 3:40 UTC www.fossilmuseum.net [Source type: FILTERED WITH BAYES]

[7] .However, proving that a fossil belongs to the crown group of a phylum is difficult, as it must display a character unique to a sub-set of the crown group.^ However, proving that a fossil belongs to the crown group of a phylum is difficult, as it must display a character unique to a sub-set of the crown group.

^ Although some texts treats this group as a member of the demospongea, some paleontologists consider stromatoporoids not as true sponges, but belonging to their own phylum.

^ Within this phylum humans belong to the sub-phylum vertebrata with all the other vertebrate animals.You can find more in...
  • Phylum - Ask.com 1 February 2010 3:40 UTC www.ask.com [Source type: General]

[7] .Further, organisms in the stem group to a phylum can bear all the aspects of the "body plan" of the phylum without all the characters necessary to fall within it.^ Phylum Chordata Phylum Chordata   The final groups of animals to be considered fall within this phylum.
  • Phylum Chordata 1 February 2010 3:40 UTC estuary.uconn.edu [Source type: FILTERED WITH BAYES]

^ Further, organisms in the stem group to a phylum can bear all the aspects of the "body plan" of the phylum without all the characters necessary to fall within it.

^ All molluscs have a similar body plan: .
  • General Biology/Classification of Living Things/Eukaryotes/Animals/Phyla - Wikibooks, collection of open-content textbooks 1 February 2010 3:40 UTC en.wikibooks.org [Source type: FILTERED WITH BAYES]

.This weakens the idea that each of the phyla represents a distinct body plan.^ This weakens the idea that each of the phyla represents a distinct body plan.

^ Jones (1985) argued that the vestimentiferan body plan was sufficiently distinct to warrant placement in a unique phylum, the Vestimentifera.
  • Phylogeny of the Annelida and allies 1 February 2010 3:40 UTC www.annelida.net [Source type: Academic]

^ Occasionally, however, different body plans are not assigned different phyla and this creates an appearance that phyla can't evolve.
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

[9]
.Based upon this definition, which some say is unreasonably affected by the chance survival of rare groups, which vastly increase the size of phyla, representatives of many modern phyla did not appear until long after the Cambrian – as late as the Carboniferous in the case of the Priapulids.^ So why did so many phyla suddenly appear in Cambrian Seas?
  • phylum level evolution 1 February 2010 3:40 UTC home.entouch.net [Source type: FILTERED WITH BAYES]

^ The Cambrian explosion was a great flowering of life forms that occurred between roughly 530 and 520 million years ago; [4] during this time organisms similar to, but not strictly members of, modern phyla existed; [5] whilst some appear to be represented in the Ediacaran biota , it remains a matter of debate whether all phyla existed prior to the explosion.
  • Phylum (biology) - Psychology Wiki 1 February 2010 3:40 UTC psychology.wikia.com [Source type: FILTERED WITH BAYES]

^ All the phyla (the second highest taxonomic category) of animals appeared around the Cambrian.
  • Introduction to Evolutionary Biology 15 September 2009 2:02 UTC www.talkorigins.org [Source type: FILTERED WITH BAYES]

[8]

Lists

Animal phyla

'Phylum' Meaning Common Name Distinguishing characteristic Species described
Acanthocephala Thorny headed worms Thorny-headed worms Reversible spiny proboscis about 750
Acoelomorpha Without gut A colon No mouth or alimentary canal
Annelida Little ring Segmented worms Multiple circular segment about 16,300 modern
Arthropoda Jointed foot(appendages) Arthropods Chitin exoskeleton 1,134,000+
Brachiopoda Arm foot Lamp shells Lophophore and pedicle between 300 and 500 extant
Bryozoa Moss animals Moss animals, sea mats Lophophore, no pedicle, ciliated tentacles about 5,000 living species
Chaetognatha Longhair jaw Arrow worms Chitinous spines either side of head, fins about 100 modern species
Chordata Cord Chordates Hollow dorsal nervous chord, notochord, pharyngeal slits, endostyle, post-anal tail about 100,000+
Cnidaria Stinging nettle Coelenterates Nematocysts (stinging cells) about 11,000
Ctenophora Comb bearer Comb jellies Eight "comb rows" of fused cilia about 100 modern species
Cycliophora Wheel carrying Symbion Circular mouth surrounded by small cilia at least 3
Echinodermata Spiny skin Echinoderms Five-fold radial symmetry in living forms, mesodermal calcified spines about 7,000 extant and 13,000 extinct species
Echiura Spine tail Spoon worms Set of hooks at posterior end about 140
Entoprocta Inside anus Goblet worm Anus inside ring of cilia about 150
Gastrotricha Hair stomach Meiofauna Two terminal adhesive tubes about 690
Gnathostomulida Jaw orifice Jaw worms about 100
Hemichordata Half cord Acorn worms, pterobranchs Stomochord in collar, pharyngeal slits about 100 living species
Kinorhyncha Motion snout Mud dragons Eleven segments, each with a dorsal plate about 150
Loricifera Corset bearer Brush heads Umbrella-like scales at each end about 122
Micrognathozoa Tiny jaw animals Accordion like extensible thorax|1
Mollusca Thin shell Mollusks / molluscs Muscular foot and mantle round shell 112,000[10]
Nematoda Thread like Round worms Round cross section, keratin cuticle 80,000 – 1 million
Nematomorpha Thread form Horsehair worms about 320
Nemertea A sea nymph Ribbon worms about 1200
Onychophora Claw bearer Velvet worms Legs tipped by chitinous claws about 200 modern
Orthonectida Straight swim Single layer of ciliated cells surrounding a mass of sex cells about 20
Phoronida Zeus's mistress Horseshoe worms U-shaped gut 20
Placozoa Plate animals 1
Platyhelminthes Flat worms Flat worms animals with bilateral symmetry and hence with distinct front and back about 25,000[11]
Porifera Pore bearer Sponges Perforated interior wall over 5,000 modern
Priapulida Penis Priapulid worms Retractable proboscis surrounded by papillae 17
Rhombozoa Lozenge animal Single axial cell surrounded by ciliated cells 75
Rotifera Wheel bearer Rotifers Anterior crown of cilia about 2000
Sipuncula Small tube Peanut worms Mouth surrounded by invertible tentacles 144–320
Tardigrada Slow step Water bears Four segmented body and head 1,000+
Xenoturbellida Strange flatworm Ciliated deuterostome 2
Total: 36 2,000,000-

Groups formerly ranked as phyla

Name as phylum Common name Current consensus
Aschelminthes Pseudocoelomates Divided into several pseudocoelomate phyla.
Craniata Subgroup of phylum Chordata; perhaps synonymous with Vertebrata.
Cephalochordata Lancelets Subphylum of phylum Chordata.
Cephalorhyncha Superphylum Scalidophora.
Enterepneusta Acorn worms Class of phylum Hemichordata.
Gephyra Peanut worms and spoon worms Divided into phyla Sipuncula and Echiura.
Mesozoa Mesozoans Divided into phyla Orthonectida and Rhombozoa.
Myxozoa Severely modified Cnidarians.
Pentastomida Tongue worms Subclass of Maxillopoda of phylum Arthropoda.
Pogonophora Beard worms Part of family Siboglinidae of phylum Annelida.
Pterobranchia Class of phylum Hemichordata.
Symplasma Glass sponges Class Hexactinellida of phylum Porifera.
Urochordata Tunicates Subphylum of phylum Chordata.
Vestimentifera Vent worms Part of family Siboglinidae of phylum Annelida.

Plant divisions

Division Meaning Common name Distinguishing characteristics
Anthocerotophyta Flower-horn plants Hornworts Horn-shaped sporophytes, no vascular system
Bryophyta Moss plants Mosses Persistent unbranched sporophytes, no vascular system
Marchantiophyta Marchantia plants Liverworts Ephemeral unbranched sporophytes, no vascular system
Lycopodiophyta Wolf foot plants Clubmosses & Spikemosses Microphyll leaves, vascular system
Pteridophyta Fern plants Ferns & Horsetails Prothallus gametophytes, vascular system
Pteridospermatophyta Fern with seeds plant Seed ferns Only known from fossils, mostly Devonian, ranking in dispute[12]
Coniferophyta Sap/pitch plants Conifers Cones containing seeds and wood composed of tracheids
Cycadophyta Palm plants Cycads Seeds, crown of compound leaves
Ginkgophyta Ginkgo plants Ginkgo, Maidenhair Seeds not protected by fruit (single species)
Gnetophyta Gnetophytes Seeds and woody vascular system with vessels
Anthophyta (or Magnoliophyta Flower plant Flowering plants Flowers and fruit, vascular system with vessels

Fungal divisions

Phylum Meaning Common name Distinguishing characteristics
Chytridiomycota Little pot mushroom Chytrids Cellulose in cell walls, flagellated gametes
Deuteromycota Second mushroom Imperfect fungi Unclassified fungi; only asexual reproduction observed
Zygomycota Yolk mushroom Zygomycetes Blend gametangia to form a zygosporangium
Glomeromycota Ball mushroom None Form arbuscular mycorrhizae with plants
Ascomycota Bag/Wineskin Mushroom Sac fungi Produce spores in an 'ascus'
Basidiomycota Basidium Mushroom Club Fungi Produce spores from a 'basidium'

See also

Notes

  1. ^ "Phylum" is adopted from the Greek φυλαί phylai, the clan-based voting groups in Greek city-states.

References

  1. ^ [http://dictionary.reference.com/browse/phylum They are frequently called divisions. The American Heritage New Dictionary of Cultural Literacy]. http://dictionary.reference.com/browse/phylum They are frequently called divisions.. 
  2. ^ Bengtson, (1986). "Introduction: The problem of the problematica,". in Hoffman, A.; Nitecki, M. H.. Problematic Fossil Taxa. Oxford,: Oxford University Press,. pp. 3–11. 
  3. ^ Valentine, James W. (2004). On the Origin of Phyla. Chicago: University Of Chicago Press. pp. 7. ISBN 0226845486. "Classifications of organisms in hierarchical systems were in use by the seventeenth and eighteenth centuries. Usually organisms were grouped according to their morphological similarities as perceived by those early workers, and those groups were then grouped according to their similarities, and so on, to form a hierarchy."
  4. ^ Parker, Andrew (2003). In the blink of an eye: How vision kick-started the big bang of evolution. Sydney: Free Press. pp. 1–4. ISBN 0743257332. "The job of an evolutionary biologist is to create dinosaurs for the devil to consume, make sense of the conflicting diversity of form – there is not always a relationship between internal and external parts. Early in the history of the subject, it became obvious that internal organisations were generally more important to the higher classification of animals than are external shapes. The internal organisation puts general restrictions on how an animal can exchange gases, obtain nutrients and reproduce."
  5. ^ Davidson, E. H; Erwin, D. H (2006). "Gene Regulatory Networks and the Evolution of Animal Body Plans". Science (American Association for the Advancement of Science) 311 (5762): 796–800. doi:10.1126/science.1113832. PMID 16469913. http://www.sciencemag.org/cgi/content/abstract/311/5762/796. 
  6. ^ Gould, S.J. (1989). Wonderful Life: The Burgess Shale and the Nature of History. W.W. Norton & Company. 
  7. ^ a b c d e f g Budd, G.E.; Jensen, S. (2000). "A critical reappraisal of the fossil record of the bilaterian phyla". Biological Reviews 75 (02): 253–295. doi:10.1017/S000632310000548X. http://www.journals.cambridge.org/abstract_S000632310000548X. Retrieved 2007-05-26. 
  8. ^ a b Briggs, D. E. G; Fortey, R. A (2005). "Wonderful strife: systematics, stem groups, and the phylogenetic signal of the Cambrian radiation". Paleobiology 31 (2 (Suppl)): 94–112. doi:10.1666/0094-8373(2005)031[0094:WSSSGA2.0.CO;2]. 
  9. ^ Budd, G.E. (1998). Lethaia (Blackwell Synergy) 31 (3): 197–210. doi:10.1111/j.1502-3931.1998.tb00508.x (inactive 2008-10-21). http://www.blackwell-synergy.com/doi/abs/10.1111/j.1502-3931.1998.tb00508.x. 
  10. ^ Feldkamp, S. (2002) Modern Biology. Holt, Rinehart, and Winston, USA. (pp. 725)
  11. ^ Species Register. "Flatworms — Phylum Platyhelminthes". Marine Discovery Centres. http://www.woodbridge.tased.edu.au/mdc/Species%20Register/phylum_platyhelminthes.htm. Retrieved 2007-04-09. 
  12. ^ ""Kingdom Plantae Tree of Life"". http://www.fossilmuseum.net/Tree_of_Life/KingdomPlantae.htm. 

External links

.
  • American Heritage Dictionary: New Latin phylum, from Greek phūlon, class.
  • Online Etymological Dictionary: from Gk.^ Below is the definition of inanity from The American Heritage Medical dictionary.
    • Top 5 Sci-Fi Cliches That Need to Die from 1UP.com 1 February 2010 3:40 UTC www.1up.com [Source type: General]

    phylon "race, stock," related to phyle "tribe, clan," and phylein "bring forth" of physikos "pertaining to nature," from physis "nature"

Wikispecies

Up to date as of January 23, 2010

From Wikispecies

Taxonavigation

Main Page
Superregnum: Superregnum
Regnum: Regnum
Subregnum: Subregnum
Infraregnum: Infraregnum
Superphylum: Superphylum
Phylum: Phylum
Subphylum: Subphylum 1 - Subphylum 2 - Subphylum 3

.This template is not a rule, not even a guideline.^ This template is not a rule, not even a guideline.

.It is a mere attempt to stimulate a discussion about the navigation in wikispecies.^ It is a mere attempt to stimulate a discussion about the navigation in wikispecies.

Please discuss this at the Village pump
edit

Simple English

A Phylum (plural: phyla) is the second highest rank used in the biological taxonomy of all organisms. The highest rank is kingdom.

Botanists usually use the word division instead of phylum.

Phylum is Phillip in the mnemonic, or a saying to help a person remember something, King Phillip Came Over For Great Spaghetti, King Phillip Came Over From Great Spain, or King Phillip Came Over For Gellato Soup, or King Philip Came Over From Greece Singing.

Simple English Wiktionary has the word meaning for:


Citable sentences

Up to date as of December 20, 2010

Here are sentences from other pages on Phylum, which are similar to those in the above article.








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