Editing Invertebrate (section)

=== Classification ===

[[Carl Linnaeus]] divided these animals into only two groups, the Insecta 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 animals and divided the original two groups into ten, by splitting Arachnida and Crustacea from the Linnean Insecta, and Mollusca, Annelida, [[Barnacle|Cirripedia]], [[Radiata]], [[Coelenterata]] and [[Infusoria]] from the Linnean Vermes. They are now classified into over 30 [[phylum|phyla]], from simple organisms such as [[sea sponge]]s and [[flatworm]]s to complex animals such as arthropods and molluscs.

==== Significance ====

Invertebrates are animals without a vertebral column. This has led to the conclusion that ''in''vertebrates are a group that deviates from the normal, vertebrates. This has been said to be because researchers in the past, such as Lamarck, viewed vertebrates as a "standard": in Lamarck's theory of evolution, he believed that characteristics acquired through the evolutionary process involved not only survival, but also progression toward a "higher form", to which humans and vertebrates were closer than invertebrates were. Although goal-directed evolution has been abandoned, the distinction of invertebrates and vertebrates persists to this day, even though the grouping has been noted to be "hardly natural or even very sharp." Another reason cited for this continued distinction is that Lamarck created a precedent through his classifications which is now difficult to escape from. It is also possible that some humans believe that, they themselves being vertebrates, the group deserves more attention than invertebrates.<ref name=rskbarnes>{{cite book|last=Barnes|first=Richard Stephen Kent|title=The Invertebrates: A Synthesis|isbn=978-0-632-04761-1|publisher=Wiley-Blackwell|year=2001|page=3}}</ref> In any event, in the 1968 edition of ''Invertebrate Zoology'', it is noted that "division of the Animal Kingdom into vertebrates and invertebrates is artificial and reflects human bias in favor of man's own relatives." The book also points out that the group lumps a vast number of species together, so that no one characteristic describes all invertebrates. In addition, some species included are only remotely related to one another, with some more related to vertebrates than other invertebrates (see [[Paraphyly]]).<ref>{{Cite book|last=Barnes |first=Robert D.|year=1968|title=Invertebrate Zoology|edition=2nd|publisher=W.B. Saunders|oclc=173898}}</ref>