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'{{Taxobox | name = Gymnospermae | fossil_range = {{fossil range|Bashkirian|0|earliest=380|[[Carboniferous]] – [[Holocene|Present]]}} | image = Gymnospermae.jpg | image_caption = Various gymnosperms. | regnum = [[Plantae]] | subregnum = [[Embryophyta]] | unranked_superdivisio = [[Spermatophyta]] | unranked_divisio = '''Gymnospermae''' (inc. {{Extinct}}; [[paraphyletic]])<br> '''Acrogymnospermae''' (extant only) | subdivision_ranks = [[Division (botany)|Divisions]] | subdivision = [[Pinophyta]] (or Coniferophyta) – Conifers<br> [[Ginkgophyta]] – ''Ginkgo''<br> [[Cycadophyta]] – Cycads<br> [[Gnetophyta]] – ''Gnetum, Ephedra, Welwitschia'' }} [[File:Encephalartos sclavoi reproductive cone.jpg|thumb|''[[Encephalartos sclavoi]]'' cone, about 30 cm long]] The '''gymnosperms''', also known as '''Acrogymnospermae''',<ref name=":1" /> are a group of [[Spermatophyte|seed-producing plants]] that includes [[Pinophyta|conifers]], [[cycad]]s, ''[[Ginkgo]]'', and [[gnetophyta|gnetophyte]]s. The term "gymnosperm" comes from the composite word in {{lang-el|γυμνόσπερμος}} ({{lang-el|γυμνός|translit=gymnos|lit=naked|label=none}} and {{lang-el|σπέρμα|translit=sperma|lit=seed|label=none}}), literally meaning "naked seeds". The name is based on the unenclosed condition of their seeds (called [[ovule]]s in their unfertilized state). The non-encased condition of their seeds contrasts with the seeds and ovules of flowering plants ([[angiosperms]]), which are enclosed within an [[Ovary (botany)|ovary]]. Gymnosperm seeds develop either on the surface of scales or leaves, which are often modified to form [[Conifer cone|cones]], or solitary as in [[Taxus|yew]], ''[[Torreya]]'', ''Ginkgo''.<ref name="TPL">{{cite web|url=http://www.theplantlist.org/browse/G/|title=Gymnosperms on The Plant List|date=|publisher=Theplantlist.org|accessdate=2013-07-24}}</ref> The gymnosperms and [[angiosperms]] together compose the [[spermatophyte]]s or seed plants. The gymnosperms are divided into six phyla. Organisms that belong to the Cycadophyta, Ginkgophyta, Gnetophyta, and Pinophyta (also known as Coniferophyta) phyla are still in existence while those in the Pteridospermales and Cordaitales phyla are now extinct.<ref name=":0">{{Cite book|title=Biology of Plants|last=Raven|first=P.H.|publisher=New York: W.H. Freeman and Co.|year=2013|isbn=|location=|pages=}}</ref> By far the largest group of living gymnosperms are the conifers (pines, cypresses, and relatives), followed by cycads, gnetophytes (''[[Gnetum]]'', ''[[Ephedra (genus)|Ephedra]]'' and ''[[Welwitschia]]''), and ''[[Ginkgo biloba]]'' (a single living species). Roots in some genera have fungal association with roots in the form of [[mycorrhiza]] (''Pinus''), while in some others (''Cycas'') small specialised roots called coralloid roots are associated with nitrogen-fixing cyanobacteria. ==Classification== {{further|Spermatophyte}} The current formal classification of the living gymnosperms is the "Acrogymnospermae", which form a [[monophyletic group]] within the [[spermatophyte]]s.<ref name=":1">{{Cite web|url=https://www.ingentaconnect.com/content/iapt/tax/2007/00000056/00000003/art00020|title=Towards a phylogenetic nomenclature of Tracheophyta|last=D.|first=Cantino, Philip|last2=A.|first2=Doyle, James|website=www.ingentaconnect.com|language=en|access-date=2018-10-18|last3=W.|first3=Graham, Sean|last4=S.|first4=Judd, Walter|last5=G.|first5=Olmstead, Richard|last6=E.|first6=Soltis, Douglas|last7=S.|first7=Soltis, Pamela|last8=J.|first8=Donoghue, Michael}}</ref><ref name=":2">{{cite journal|last1=Christenhusz|first1=M.J.M.|last2=Reveal|first2=J.L.|last3=Farjon|first3=A.|last4=Gardner|first4=M.F.|last5=Mill|first5=R.R.|last6=Chase|first6=M.W.|year=2011|title=A new classification and linear sequence of extant gymnosperms|url=http://www.mapress.com/phytotaxa/content/2011/f/pt00019p070.pdf|journal=Phytotaxa|volume=19|issue=|pages=55–70|doi=10.11646/phytotaxa.19.1.3}}</ref> The wider "Gymnospermae" group eat my ass whoreincludes extinct gymnosperms and is thought to be [[Paraphyly|paraphyletic]]. The fossil record of gymnosperms includes many distinctive [[taxa]] that do not belong to the four modern groups, including seed-bearing trees that have a somewhat [[fern]]-like vegetative morphology (the so-called "seed ferns" or [[pteridosperm]]s).<ref>Hilton, Jason, and Richard M. Bateman. 2006. Pteridosperms are the backbone of seed-plant phylogeny. ''Journal of the Torrey Botanical Society'' 133: 119–168 ([http://www.bioone.org/perlserv/?request=get-abstract&doi=10.3159%2F1095-5674(2006)133%5B119%3APATBOS%5D2.0.CO%3B2&ct=1 abstract])</ref> When fossil gymnosperms such as these and the [[Bennettitales]], [[glossopterid]]s, and ''Caytonia'' are considered, it is clear that angiosperms are nested within a larger gymnospermae clade, although which group of gymnosperms is their closest relative remains unclear. The extant gymnosperms include 12 main families and 83 genera which contain more than 1000 known species.<ref name="TPL" /><ref name=":2" /><ref name="Christenhusz-Byng2016">{{cite journal |author1=Christenhusz, M. J. M. |author2=Byng, J. W. | year = 2016 | title = The number of known plants species in the world and its annual increase | journal = Phytotaxa | volume = 261 | pages = 201–217 | url = http://biotaxa.org/Phytotaxa/article/download/phytotaxa.261.3.1/20598 | doi = 10.11646/phytotaxa.261.3.1 | issue = 3 }}</ref> Subclass '''[[Cycadidae]]''' *Order '''[[Cycadales]]''' **Family '''[[Cycadaceae]]''': ''Cycas'' **Family '''[[Zamiaceae]]''': ''Dioon'', ''Bowenia'', ''Macrozamia'', ''Lepidozamia'', ''Encephalartos'', ''Stangeria'', ''Ceratozamia'', ''Microcycas'', ''Zamia''. Subclass '''[[Ginkgoidae]]''' *Order '''[[Ginkgoales]]''' **Family '''[[Ginkgoaceae]]''': ''Ginkgo'' Subclass '''[[Gnetidae]]''' *Order '''[[Welwitschiales]]''' **Family '''[[Welwitschiaceae]]''': ''Welwitschia'' *Order '''[[Gnetales]]''' **Family '''[[Gnetaceae]]''': ''Gnetum'' *Order '''[[Ephedrales]]''' **Family '''[[Ephedraceae]]''': ''Ephedra'' Subclass '''[[Pinidae]]''' *Order '''[[Pinales]]''' **Family '''[[Pinaceae]]''': ''Cedrus'', ''Pinus'', ''Cathaya'', ''Picea'', ''Pseudotsuga'', ''Larix'', ''Pseudolarix'', ''Tsuga'', ''Nothotsuga'', ''Keteleeria'', ''Abies'' *Order '''[[Araucariales]]''' **Family '''[[Araucariaceae]]''': ''Araucaria'', ''Wollemia'', ''Agathis'' **Family '''[[Podocarpaceae]]''': ''Phyllocladus'', ''Lepidothamnus'', ''Prumnopitys'', ''Sundacarpus'', ''Halocarpus'', ''Parasitaxus'', ''Lagarostrobos'', ''Manoao'', ''Saxegothaea'', ''Microcachrys'', ''Pherosphaera'', ''Acmopyle'', ''Dacrycarpus'', ''Dacrydium'', ''Falcatifolium'', ''Retrophyllum'', ''Nageia'', ''Afrocarpus'', ''Podocarpus'' *Order '''Cupressales''' **Family '''[[Sciadopityaceae]]''': ''Sciadopitys'' **Family '''[[Cupressaceae]]''': ''Cunninghamia'', ''Taiwania'', ''Athrotaxis'', ''Metasequoia'', ''Sequoia'', ''Sequoiadendron'', ''Cryptomeria'', ''Glyptostrobus'', ''Taxodium'', ''Papuacedrus'', ''Austrocedrus'', ''Libocedrus'', ''Pilgerodendron'', ''Widdringtonia'', ''Diselma'', ''Fitzroya'', ''Callitris'', ''Actinostrobus'', ''Neocallitropsis'', ''Thujopsis'', ''Thuja'', ''Fokienia'', ''Chamaecyparis'', ''Cupressus'', ''Juniperus'', ''Calocedrus'', ''Tetraclinis'', ''Platycladus'', ''Microbiota'' **Family '''[[Taxaceae]]''': ''Austrotaxus'', ''Pseudotaxus'', ''Taxus'', ''Cephalotaxus'', ''Amentotaxus'', ''Torreya'' ==Diversity and origin== There are over 1000 living species of gymnosperm.<ref name="TPL" /> It is widely accepted that the gymnosperms originated in the late [[Carboniferous]] period, replacing the [[Lycopodiophyta|lycopsid]] rainforests of the tropical region.<ref name="SahneyBentonFerry2010RainforestCollapse">{{cite journal | url=http://geology.geoscienceworld.org/cgi/content/abstract/38/12/1079 | author= Sahney, S. | author2= Benton, M.J. | author3= Falcon-Lang, H.J. | last-author-amp= yes | year=2010 | title= Rainforest collapse triggered Pennsylvanian tetrapod diversification in Euramerica | journal=Geology | volume = 38 | pages = 1079–1082 | format=PDF | doi=10.1130/G31182.1 | issue=12 | bibcode=2010Geo....38.1079S}}</ref><ref>Campbell and Reece; Biology, Eighth edition</ref> This appears to have been the result of a whole [[Gene duplication|genome duplication]] event around {{ma|319}}.<ref name="Jiao2011">Jiao Y, Wickett NJ, Ayyampalayam S, Chanderbali AS, Landherr L, Ralph PE, Tomsho LP, Hu Y, Liang H, [[Soltis PS]], [[Douglas E. Soltis|Soltis DE]], Clifton SW, Schlarbaum SE, Schuster SC, Ma H, Leebens-Mack J, Depamphilis CW (2011) Ancestral polyploidy in seed plants and angiosperms. Nature</ref> Early characteristics of seed plants were evident in fossil [[progymnosperms]] of the late [[Devonian]] period around 383 million years ago. It has been suggested that during the mid-Mesozoic era, pollination of some extinct groups of gymnosperms was by extinct species of [[Mecoptera|scorpionflies]] that had specialized [[proboscis]] for feeding on pollination drops. The scorpionflies likely engaged in pollination mutualisms with gymnosperms, long before the similar and independent coevolution of nectar-feeding insects on angiosperms.<ref>{{cite journal | last1 = Ollerton | first1 = J. | last2 = Coulthard | first2 = E. | year = 2009 | title = Evolution of Animal Pollination | url = | journal = Science | volume = 326 | issue = 5954| pages = 808–809 | doi = 10.1126/science.1181154 | pmid = 19892970 | bibcode = 2009Sci...326..808O }}</ref><ref name="Ren">{{cite journal | last1 = Ren | first1 = D | last2 = Labandeira | first2 = CC | last3 = Santiago-Blay | first3 = JA | last4 = Rasnitsyn | first4 = A | last5 = Shih | first5 = CK | last6 = Bashkuev | first6 = A | last7 = Logan | first7 = MA | last8 = Hotton | first8 = CL | last9 = Dilcher | first9 = D. |displayauthors=4 | year = 2009 | title = A Probable Pollination Mode Before Angiosperms: Eurasian, Long-Proboscid Scorpionflies | url = | journal = Science | volume = 326 | issue = 5954| pages = 840–847 | doi = 10.1126/science.1178338 | pmid = 19892981 | pmc = 2944650 | bibcode = 2009Sci...326..840R }}</ref> Evidence has also been found that mid-Mesozoic gymnosperms were pollinated by [[Kalligrammatidae|Kalligrammatid lacewings]], a now-extinct genus with members which (in an example of [[convergent evolution]]) resembled the modern butterflies that arose far later.<ref>{{cite journal | title=The evolutionary convergence of mid-Mesozoic lacewings and Cenozoic butterflies | journal = Proceedings of the Royal Society B: Biological Sciences | last1=Labandeira | first1=Conrad C. | last2=Yang | first2=Qiang | last3=Santiago-Blay | first3=Jorge A. | last4=Hotton | first4=Carol L. | last5=Monteiro | first5=Antónia | last6=Wang | first6=Yong-Jie | last7=Goreva | first7=Yulia | last8=Shih | first8=ChungKun | last9=Siljeström | first9=Sandra | last10=Rose | first10=Tim R. | last11=Dilcher | first11=David L. | last12=Ren | first12=Dong | volume = 283 | issue = 1824| doi=10.1098/rspb.2015.2893 | pages=20152893 | pmid=26842570 | pmc=4760178| year = 2016 }}</ref> [[File:Zamia integrifolia02.jpg|thumb|''Zamia integrifolia,'' a cycad native to Florida]] [[Conifer]]s are by far the most abundant extant group of gymnosperms with six to eight families, with a total of 65–70 genera and 600–630 species (696 accepted names).<ref name="Catalogue">[http://www.catalogueoflife.org/show_database_details.php?database_name=Conifer+Database Catalogue of Life: 2007 Annual checklist – Conifer database] {{webarchive |url=https://web.archive.org/web/20090115190412/http://www.catalogueoflife.org/show_database_details.php?database_name=Conifer+Database |date=January 15, 2009 }}</ref> Conifers are woody plants and most are evergreens.<ref>Campbell, Reece, "Phylum Coniferophyta."Biology. 7th. 2005. Print. P.595</ref> The [[leaf|leaves]] of many conifers are long, thin and needle-like, other species, including most [[Cupressaceae]] and some [[Podocarpaceae]], have flat, triangular scale-like leaves. ''[[Agathis]]'' in Araucariaceae and ''[[Nageia]]'' in Podocarpaceae have broad, flat strap-shaped leaves. [[Cycad]]s are the next most abundant group of gymnosperms, with two or three families, 11 genera, and approximately 338 species. A majority of cycads are native to tropical climates and are most abundantly found in regions near the equator. The other extant groups are the 95–100 species of [[Gnetum|Gnetale]]s and one species of [[Ginkgo]].<ref name=":0" /> {{Barlabel |size=4 |at1=2|bar1=green|label1=Gymnospermae |cladogram= {{Clade |label1=[[Spermatophyta]] |1={{Cladex |1=[[Pteridospermatophyta]] {{extinct}}|barbegin1=green |2={{Cladex |1=Acrogymnospermae|barend1=green |2=[[Angiospermae]] }} }} }} }} ==Uses== Gymnosperms have major economic uses. Pine, fir, spruce, and cedar are all examples of conifers that are used for [[lumber]], paper production, and resin. Some other common uses for gymnosperms are [[soap]], [[varnish]], [[nail polish]], food, gum, and [[perfume]]s. ==Life cycle== [[File:Gymnosperm life cycle (en).png|thumb|Example of gymnosperm lifecycle]] Gymnosperms, like all [[vascular plants]], have a sporophyte-dominant life cycle, which means they spend most of their life cycle with diploid cells, while the [[gametophyte]] (gamete-bearing phase) is relatively short-lived. Two spore types, microspores and megaspores, are typically produced in pollen cones or ovulate cones, respectively. Gametophytes, as with all heterosporous plants, develop within the spore wall. Pollen grains (microgametophytes) mature from microspores, and ultimately produce sperm cells. Megagametophytes develop from megaspores and are retained within the ovule. Gymnosperms produce multiple [[Archegonium|archegonia]], which produce the female gamete. During pollination, pollen grains are physically transferred between plants from the pollen cone to the ovule. Pollen is usually moved by wind or insects. Whole grains enter each ovule through a microscopic gap in the ovule coat ([[integument]]) called the micropyle. The pollen grains mature further inside the ovule and produce sperm cells. Two main modes of fertilization are found in gymnosperms. Cycads and ''[[Ginkgo]]'' have motile sperm that swim directly to the egg inside the ovule, whereas conifers and [[gnetophyte]]s have sperm with no [[flagella]] that are moved along a [[pollen tube]] to the egg. After [[Fertilisation|syngamy]] (joining of the sperm and egg cell), the zygote develops into an embryo (young sporophyte). More than one embryo is usually initiated in each gymnosperm seed. The mature seed comprises the embryo and the remains of the female gametophyte, which serves as a food supply, and the seed coat.<ref name="Walters1996">{{Cite book| last = Walters | first = Dirk R Walters Bonnie By| year = 1996| title = Vascular plant taxonomy| page = 124| url = https://books.google.com/?id=ZbaNxSnNoecC&pg=PA124&dq=Gymnosperm+seeds| isbn = 978-0-7872-2108-9| publisher = Kendall/Hunt Pub. Co.| location = Dubuque, Iowa}}</ref> ==Genetics== The first published sequenced genome for any gymnospermae was the genome of ''[[Picea abies]]'' in 2013.<ref>{{cite journal | title = The Norway spruce genome sequence and conifer genome evolution | journal = Nature | volume = 497 | issue = 7451| pages = 579–584 | doi = 10.1038/nature12211 | pmid=23698360 | date=May 2013 | last1 = Nystedt | first1 = B | last2 = Street | first2 = NR | last3 = Wetterbom | first3 = A | display-authors = etal | bibcode = 2013Natur.497..579N }}</ref> ==References== {{Reflist|30em}} ==External links== {{Commonscat|Gymnosperms}} *[http://www.conifers.org/ Gymnosperm Database] *[https://web.archive.org/web/20080409044237/http://www.huh.harvard.edu/research/mathews-lab/atolHtmlSite/ Gymnosperms on the Tree of Life] *{{Cite EB1911|wstitle=Gymnosperms|author=Albert Seward|author-link=Albert Seward|short=x}} {{Clear}} {{Botany}} {{Plant classification}} {{Taxonbar|from=Q133712}} {{Authority control}} [[Category:Gymnosperms| 01]] [[Category:Extant Late Devonian first appearances]]'