Menu
Home
People
Places
Arts
History
Plants & Animals
Science
Life & Culture
Technology
Reference.org
Outline of life forms
open-in-new
<h2 id="archaea">Archaea</h2> <ul><li><a href="/facts/Archaea/Adxh0aHw">Archaea</a> – a domain of single-celled microorganisms, morphologically similar to bacteria, but they possess genes and several metabolic pathways that are more closely related to those of eukaryotes, notably the enzymes involved in transcription and translation. Many archaea are extremophiles, which means living in harsh environments, such as hot springs and salt lakes, but they have since been found in a broad range of habitats. <ul><li><a href="/facts/Thermoproteota/S1gX5vGh">Thermoproteota</a> – a phylum of the Archaea kingdom. Initially <ul><li><a href="/facts/Thermoprotei/csvdC7m8">Thermoprotei</a> <ul><li><a href="/facts/Sulfolobales/gxG73yNM">Sulfolobales</a> – grow in terrestrial volcanic hot springs with optimum growth occurring</li></ul></li></ul></li> <li><a href="/facts/Euryarchaeota/kYm3IxyF">Euryarchaeota</a> – In the taxonomy of microorganisms <ul><li><a href="/facts/Haloarchaea/8x5CYcB3">Haloarchaea</a> <ul><li><a href="/facts/Halobacteriales/J9I30bcH">Halobacteriales</a> – in taxonomy, the Halobacteriales are an order of the Halobacteria, found in water saturated or nearly saturated with salt.</li></ul></li> <li><a href="/facts/Methanobacteria/KyyTpf4f">Methanobacteria</a> <ul><li><a href="/facts/Methanobacteriales/ufCaVyMt">Methanobacteriales</a> – information including symptoms, causes, diseases, symptoms, treatments, and other medical and health issues.</li></ul></li> <li><a href="/facts/Methanococci/gjeweUBf">Methanococci</a> <ul><li><a href="/facts/Methanococcales/uj86m8IC">Methanococcales</a> aka <i><a href="/facts/Methanocaldococcus_jannaschii/T2TnVd9o">Methanocaldococcus jannaschii</a></i> – thermophilic methanogenic archaea, meaning that it thrives at high temperatures and produces methane</li></ul></li> <li><a href="/facts/Methanomicrobia/9A3WjTtb">Methanomicrobia</a> <ul><li><a href="/facts/Methanosarcinales/bp46CbKG">Methanosarcinales</a> – In taxonomy, the Methanosarcinales are an order of the Methanomicrobia</li></ul></li> <li><a href="/facts/Methanopyri/8EuGtfLu">Methanopyri</a> <ul><li><a href="/facts/Methanopyrales/AeYMSGSm">Methanopyrales</a> – In taxonomy, the Methanopyrales are an order of the methanopyri.</li></ul></li> <li><a href="/facts/Thermococci/zb3F7ygP">Thermococci</a> <ul><li><a href="/facts/Thermococcales/vWxeTEnT">Thermococcales</a></li></ul></li> <li><a href="/facts/Thermoplasmata/QcjEq88m">Thermoplasmata</a> <ul><li><a href="/facts/Thermoplasmatales/9NL4LMm6">Thermoplasmatales</a> – An order of aerobic, thermophilic archaea, in the kingdom</li></ul></li></ul></li> <li><a href="/facts/Halophiles/UKBTAPls">Halophiles</a> – organisms that thrive in high salt concentrations</li> <li><a href="/facts/Korarchaeota/3zzSq09X">Korarchaeota</a> <ul><li><a href="/facts/Korarchaeum_cryptofilum/Adxh0aHw">Korarchaeum cryptofilum</a> – These archaea have only been found in high temperature hydrothermal environments, particularly hot springs</li></ul></li> <li><a href="/facts/Lokiarchaeota/MJu0v3oK">Lokiarchaeota</a></li> <li><a href="/facts/Methanogens/6tRT6LyH">Methanogens</a></li> <li><a href="/facts/Nanoarchaeota/Vpps9UMl">Nanoarchaeota</a> <ul><li><i><a href="/facts/Nanoarchaeum_equitans/ewUPFb5A">Nanoarchaeum equitans</a></i> – This organism was discovered in 2002 and lives inside another archaea.</li></ul></li> <li><a href="/facts/Psychrophiles/8fESUsxP">Psychrophiles</a> – (sigh-crow-files)</li> <li><a href="/facts/Nitrososphaerota/0M5s6Ww1">Nitrososphaerota</a> – a phylum of the Archaea proposed in 2008 after the genome of <i><a href="/facts/Cenarchaeum_symbiosum/anDcrE7l">Cenarchaeum symbiosum</a></i></li> <li><a href="/facts/Thermophilic/HGuP161d">thermophilic</a> – (a thermophile is an organism)</li></ul></li></ul> <h2 id="bacteria">Bacteria</h2> <ul><li><a href="/facts/Bacteria/wC8xSCsU">Bacteria</a> <ul><li><a href="/facts/Gram_positive/H6WYQ17e">Gram positive</a> no <a href="/facts/Bacterial_outer_membrane/75HPUFEV">outer membrane</a> <ul><li><a href="/facts/Actinomycetota/ShmuHEND">Actinomycetota</a> (high-<a href="/facts/GC-content/nRoVl7gw">G+C</a>)</li> <li><a href="/facts/Bacillota/FxP0p0n8">Bacillota</a> (low-<a href="/facts/GC-content/nRoVl7gw">G+C</a>)</li> <li><a href="/facts/Mycoplasmatota/egGka06X">Mycoplasmatota</a> (no <a href="/facts/Cell_wall/DYXJVrnw">wall</a>)</li></ul></li> <li><a href="/facts/Gram_negative/S1PbVtp4">Gram negative</a> <a href="/facts/Bacterial_outer_membrane/75HPUFEV">outer membrane</a> present <ul><li><a href="/facts/Aquificota/enEmhVjX">Aquificota</a></li> <li><a href="/facts/Deinococcota/8H2ssbW9">Deinococcota</a></li> <li><a href="/facts/Fibrobacterota/feqP33j9">Fibrobacterota</a>/<a href="/facts/Chlorobiota/quB68CUc">Chlorobiota</a>/<a href="/facts/Bacteroidota/D8vX8BHh">Bacteroidota</a> (<a href="/facts/Sphingobacteria_(phylum)/EmmgJfdJ">FCB group</a>)</li> <li><a href="/facts/Frateuria_aurantia/K7Ea3wYw">Frateuria aurantia</a> (a species of Proteobacteria)</li> <li><a href="/facts/Fusobacteriota/JhCYSFjp">Fusobacteriota</a></li> <li><a href="/facts/Gemmatimonadota/98XYgBam">Gemmatimonadota</a></li> <li><a href="/facts/Nitrospirota/9BNaqf8a">Nitrospirota</a></li> <li><a href="/facts/Planctomycetota/pANx8H74">Planctomycetota</a>/<a href="/facts/Verrucomicrobiota/3gNUfft1">Verrucomicrobiota</a>/<a href="/facts/Chlamydiota/DgfPBw38">Chlamydiota</a> (<a href="/facts/Planctobacteria/mb4N9lwA">PVC group</a>)</li> <li><a href="/facts/Pseudomonadota/ggjeK6II">Pseudomonadota</a>/<a href="/facts/Myxococcota/zqFLbrNx">Myxococcota</a>/<a href="/facts/Bdellovibrionota/tDIFcm9C">Bdellovibrionota</a>/<a href="/facts/Campylobacterota/tXKmFDSc">Campylobacterota</a></li> <li><a href="/facts/Spirochaetota/UAy2oy6I">Spirochaetota</a></li> <li><a href="/facts/Synergistota/20DD5qyo">Synergistota</a></li></ul></li> <li>Unknown / ungrouped <ul><li><a href="/facts/Acidobacteriota/8fId9Szq">Acidobacteriota</a></li> <li><a href="/facts/Chloroflexota/glhWhcDT">Chloroflexota</a></li> <li><a href="/facts/Chrysiogenota/Q0qXYPF9">Chrysiogenota</a></li> <li><a href="/facts/Cyanobacteria/S8bKxIU9">Cyanobacteria</a></li> <li><a href="/facts/Deferribacterota/3fF11eKX">Deferribacterota</a></li> <li><a href="/facts/Dictyoglomota/Jlx3tQT7">Dictyoglomota</a></li> <li><a href="/facts/Thermodesulfobacteriota/A1H4tz0F">Thermodesulfobacteriota</a></li> <li><a href="/facts/Thermotogota/GggLdxhs">Thermotogota</a></li></ul></li></ul></li></ul> <h2 id="eukaryote">Eukaryote</h2> <ul><li><a href="/facts/Eukaryote/SkwyPLMA">Eukaryote</a> – organisms whose cells contain complex structures enclosed within membranes. <ul><li><a href="/facts/Unikont/nUgdL21F">Unikonta</a> <ul><li><a href="/facts/Opisthokonta/y2AkoxVG">Opisthokonta</a> <ul><li><a href="/facts/Outline_of_animals/5uUCxyxu">Animal</a> – <a href="/facts/Multicellular/rk8QBF7o">multicellular</a> <a href="/facts/Eukaryotic/SkwyPLMA">eukaryotic</a> organisms that form the <a href="/facts/Kingdom_(biology)/QGRKbHos">biological kingdom</a> Animalia. With few exceptions, animals <a href="/facts/Heterotroph/wtzlgBtz">consume organic material</a>, <a href="/facts/Cellular_respiration/kb6gpsvL">breathe oxygen</a>, are <a href="/facts/Motility/Df5BECHL">able to move</a>, <a href="/facts/Sexual_reproduction/hmsXy53s">reproduce sexually</a>, and grow from a hollow sphere of cells, the <a href="/facts/Blastula/sJVSBmbH">blastula</a>, during <a href="/facts/Embryogenesis/1lFY4EoW">embryonic development</a>. <ul><li>Subkingdom <a href="/facts/Parazoa/E9T2WFWA">Parazoa</a> <ul><li><a href="/facts/Sponge/E9T2WFWA">Porifera</a></li> <li><a href="/facts/Placozoa/F9NcYdAz">Placozoa</a></li></ul></li> <li>Subkingdom <a href="/facts/Eumetazoa/aTu1J8mo">Eumetazoa</a> <ul><li><a href="/facts/Radiata/89tVkW0k">Radiata</a> (unranked) <ul><li><a href="/facts/Ctenophora/3eGCj2e8">Ctenophora</a></li> <li><a href="/facts/Cnidaria/d0HRc6w0">Cnidaria</a></li></ul></li> <li><a href="/facts/Bilateria/nfUwVYrx">Bilateria</a> (unranked) <ul><li><a href="/facts/Orthonectida/WxNDRxly">Orthonectida</a></li> <li><a href="/facts/Rhombozoa/bXG641P6">Rhombozoa</a></li> <li><a href="/facts/Acoelomorpha/9sf0zjLv">Acoelomorpha</a></li> <li><a href="/facts/Chaetognatha/6y4xYXtJ">Chaetognatha</a></li> <li>Superphylum <a href="/facts/Deuterostomia/Uc3V9mGA">Deuterostomia</a> <ul><li><a href="/facts/Chordata/AldL6ARm">Chordata</a></li> <li><a href="/facts/Hemichordata/51nn9BUX">Hemichordata</a></li> <li><a href="/facts/Echinoderm/j2rd8qwt">Echinodermata</a></li> <li><a href="/facts/Xenoturbellida/UlUubDrv">Xenoturbellida</a></li> <li><a href="/facts/Vetulicolia/KkBH8Pmj">Vetulicolia</a> <a href="/facts/Extinction/24p5NP2q">†</a></li></ul></li> <li><a href="/facts/Protostomia/XLtWYdt8">Protostomia</a> (unranked) <ul><li>Superphylum <a href="/facts/Ecdysozoa/L3hxqnxA">Ecdysozoa</a> <ul><li><a href="/facts/Kinorhyncha/UGERFGXe">Kinorhyncha</a></li> <li><a href="/facts/Loricifera/lM57Dh9V">Loricifera</a></li> <li><a href="/facts/Priapulida/Bm3KobUK">Priapulida</a></li> <li><a href="/facts/Nematoda/yLMJ43Eu">Nematoda</a></li> <li><a href="/facts/Nematomorpha/eTgHYMoj">Nematomorpha</a></li> <li><a href="/facts/Lobopodia/6s3N82pP">Lobopodia</a></li> <li><a href="/facts/Onychophora/CVn4wdwx">Onychophora</a></li> <li><a href="/facts/Tardigrada/WQUg0IS9">Tardigrada</a></li> <li><a href="/facts/Arthropoda/JKJLTFzp">Arthropoda</a></li></ul></li> <li>Superphylum <a href="/facts/Platyzoa/rbVpqMDr">Platyzoa</a> <ul><li><a href="/facts/Platyhelminthes/lvqbrb2V">Platyhelminthes</a></li> <li><a href="/facts/Gastrotricha/fyJgA4at">Gastrotricha</a></li> <li><a href="/facts/Rotifera/Gy8DKrFd">Rotifera</a></li> <li><a href="/facts/Acanthocephala/dJqMq426">Acanthocephala</a></li> <li><a href="/facts/Gnathostomulida/fY4S89JA">Gnathostomulida</a></li> <li><a href="/facts/Micrognathozoa/nPq3zNv1">Micrognathozoa</a></li> <li><a href="/facts/Cycliophora/XSM7QM8F">Cycliophora</a></li></ul></li> <li>Superphylum <a href="/facts/Lophotrochozoa/sz5UzpHC">Lophotrochozoa</a> <ul><li><a href="/facts/Sipuncula/uJxuIwvB">Sipuncula</a></li> <li><a href="/facts/Hyolitha/0rB1dbKM">Hyolitha</a> <a href="/facts/Extinction/24p5NP2q">†</a></li> <li><a href="/facts/Nemertea/D1HKC5NT">Nemertea</a></li> <li><a href="/facts/Phoronida/cDXn9pBV">Phoronida</a></li> <li><a href="/facts/Bryozoa/obAgpA6M">Bryozoa</a></li> <li><a href="/facts/Entoprocta/IHpCbHfj">Entoprocta</a></li> <li><a href="/facts/Brachiopoda/XVBnEPj1">Brachiopoda</a></li> <li><a href="/facts/Mollusca/1elgknsQ">Mollusca</a></li> <li><a href="/facts/Annelida/PQvb7NAM">Annelida</a></li> <li><a href="/facts/Echiura/CYxsCTIc">Echiura</a></li></ul></li></ul></li></ul></li></ul></li></ul></li> <li><a href="/facts/Mesomycetozoa/lN6FJPW1">Mesomycetozoa</a></li> <li><a href="/facts/Outline_of_fungi/5LRlSXKP">Fungi</a> – any member of the group of <a href="/facts/Eukaryote/SkwyPLMA">eukaryotic</a> organisms that includes unicellular microorganisms such as <a href="/facts/Yeast/eGD24nfI">yeasts</a> and <a href="/facts/Mold_(fungus)/7nHqptM7">molds</a>, as well as multicellular fungi that produce familiar fruiting forms known as <a href="/facts/Mushrooms/sRdY6lfe">mushrooms</a>. <ul><li><a href="/facts/Blastocladiomycota/2oX4eFo7">Blastocladiomycota</a> <ul><li><a href="/facts/Chytridiomycota/EEn8uquv">Chytridiomycota</a></li> <li><a href="/facts/Glomeromycota/kfbrKPT3">Glomeromycota</a></li> <li><a href="/facts/Microsporidia/z01Q4Xfl">Microsporidia</a></li> <li><a href="/facts/Neocallimastigomycota/maqNQ0ok">Neocallimastigomycota</a></li></ul></li> <li><a href="/facts/Dikarya/F6XFY1fl">Dikarya</a> (inc. <a href="/facts/Deuteromycota/SBSevvF5">Deuteromycota</a>) <ul><li><a href="/facts/Ascomycota/4GJdsf2e">Ascomycota</a> <ul><li><a href="/facts/Pezizomycotina/FvAt3UKx">Pezizomycotina</a></li> <li><a href="/facts/Saccharomycotina/79W235sk">Saccharomycotina</a></li> <li><a href="/facts/Taphrinomycotina/H1LvEV1o">Taphrinomycotina</a></li></ul></li> <li><a href="/facts/Basidiomycota/LuFeC7D2">Basidiomycota</a> <ul><li><a href="/facts/Agaricomycotina/jD2qdLvS">Agaricomycotina</a></li> <li><a href="/facts/Pucciniomycotina/oAdz4pkN">Pucciniomycotina</a></li> <li><a href="/facts/Ustilaginomycotina/ocs28yuq">Ustilaginomycotina</a></li></ul></li></ul></li> <li>Subphyla <i><a href="/facts/Incertae_sedis/kWyo2wYR">incertae sedis</a></i> <ul><li><a href="/facts/Entomophthoromycotina/gEG5m1Xh">Entomophthoromycotina</a></li> <li><a href="/facts/Kickxellomycotina/txLfNgqs">Kickxellomycotina</a></li> <li><a href="/facts/Mucoromycotina/IoDD2cEL">Mucoromycotina</a></li> <li><a href="/facts/Zoopagomycotina/ljnY7rvA">Zoopagomycotina</a></li></ul></li></ul></li></ul></li> <li><a href="/facts/Amoebozoa/6wBSrR9h">Amoebozoa</a> <ul><li><a href="/facts/Conosa/K2j4dSqQ">Conosa</a> <ul><li><a href="/facts/Mycetozoa/EgD4yUNs">Mycetozoa</a> (slime-molds)</li> <li><a href="/facts/Archamoebae/Vv9YSzzt">Archamoebae</a></li></ul></li> <li><a href="/facts/Lobosa/c2lLsC0V">Lobosa</a></li> <li><a href="/facts/Protamoebae/uPpzKymr">Protamoebae</a></li></ul></li></ul></li> <li><a href="/facts/Bikonta/gm3cm2Ge">Bikonta</a> <ul><li><a href="/facts/Apusozoa/rlcYEPEl">Apusozoa</a></li> <li><a href="/facts/Excavata/qnRADFMd">Excavata</a></li> <li><a href="/facts/Archaeplastida/64UGVyKu">Archaeplastida</a> (plants, broadly defined) <ul><li><a href="/facts/Glaucophyta/gTuqKfI3">Glaucophyta</a> – glaucophytes</li> <li><a href="/facts/Rhodophyta/jCeIc7Kq">Rhodophyceae</a> – red algae</li> <li><a href="/facts/Viridiplantae/YAn2Yzck">Chloroplastida</a></li> <li><a href="/facts/Chlorophyta/hRL4moDT">Chlorophyta</a> – green algae (part)</li> <li><a href="/facts/Ulvophyceae/Ic9h3EIY">Ulvophyceae</a></li> <li><a href="/facts/Trebouxiophyceae/xHoG9Kdh">Trebouxiophyceae</a></li> <li><a href="/facts/Chlorophyceae/K4QxNQu2">Chlorophyceae</a></li> <li><a href="/facts/Chlorodendrales/NTNhaqz0">Chlorodendrales</a> – green algae (part)</li> <li><a href="/facts/Prasinophyte/PfoEHVC4">Prasinophytae</a> – green algae (part)</li> <li><i><a href="/facts/Mesostigma/Mud6yAeJ">Mesostigma</a></i></li> <li><a href="/facts/Charophyta/pIudJKKj">Charophyta</a> <i>sensu lato</i> – green algae (part) and land plants <ul><li><a href="/facts/Streptophytina/KtjqwQg3">Streptophytina</a> – stoneworts and land plants <ul><li><a href="/facts/Charales/rr9rLEbV">Charales</a> – stoneworts</li> <li><a href="/facts/Plantae/X5BMDMvS">Plantae</a> – land plants (embryophytes)</li></ul></li></ul></li></ul></li> <li><a href="/facts/SAR_supergroup/XCgKgojf">SAR supergroup</a> <ul><li><a href="/facts/Alveolata/3TrXju5S">Alveolata</a></li> <li><a href="/facts/Heterokont/WFevSvg2">Heterokonta</a></li> <li><a href="/facts/Rhizaria/Jc0DxKyp">Rhizaria</a></li></ul></li></ul></li></ul></li></ul> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Outline_of_biology/pI02Mcpl">Outline of biology</a></li> <li><a href="/facts/Earliest_known_life_forms/5voHrbwL">Earliest known life forms</a></li> <li><a href="/facts/Extraterrestrial_life/arxCPFTQ">Extraterrestrial life</a></li> <li><a href="/facts/Hypothetical_types_of_biochemistry/EsfhbBXC">Hypothetical types of biochemistry</a></li> <li><a href="/facts/Life/DNw7NUId">Life</a></li> <li><a href="/facts/Marine_life/TF5MGzFb">Marine life</a></li> <li><a href="/facts/Organism/j8JkL09u">Organism</a></li></ul> <h2 id="external-links">External links</h2> <ul><li><a href="https://web.archive.org/web/20051222163318/http://sn2000.taxonomy.nl/Main/Classification/1.htm">Life</a> (Systema Naturae 2000)</li> <li><a href="https://www.biolib.cz/en/taxon/id14772">Vitae</a> (BioLib)</li> <li><a href="https://web.archive.org/web/20140715055239/http://taxonomicon.taxonomy.nl/TaxonTree.aspx?id=1&src=0">Biota</a> (Taxonomicon)</li> <li>Wikispecies – a free directory of life</li> <li><a href="http://microbewiki.kenyon.edu/index.php/MicrobeWiki">MicrobeWiki</a>, extensive <a href="/facts/Wiki/uCKCEzqb">wiki</a> about <a href="http://microbewiki.kenyon.edu/index.php/Microbial_Biorealm">bacteria</a> and <a href="http://microbewiki.kenyon.edu/index.php/Viral_Biorealm">viruses</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>"life form". World English Dictionary. Dictionary.com. 2009. <a href="http://dictionary.reference.com/browse/life+form" target="_blank">http://dictionary.reference.com/browse/life+form</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>"life form". Online Oxford Dictionary of English. Oxford University Press. 2005. Archived from the original on 2011-08-11. <a href="https://archive.today/20110811050341/http://dws-sketch.uk.oup.com/cgi-bin/onlineOde/print_entry.cgi?id=L002092044&match_point=2&lemma=&right_column_mode=synonyms&caption_style=long&search_type=simple" target="_blank">https://archive.today/20110811050341/http://dws-sketch.uk.oup.com/cgi-bin/onlineOde/print_entry.cgi?id=L002092044&match_point=2&lemma=&right_column_mode=synonyms&caption_style=long&search_type=simple</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Kunin, W.E.; Gaston, Kevin, eds. (31 December 1996). The Biology of Rarity: Causes and consequences of rare—common differences. ISBN 978-0412633805. Retrieved 26 May 2015. <a href="978-0412633805" target="_blank">978-0412633805</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Stearns, Beverly Peterson; Stearns, S. C.; Stearns, Stephen C. (2000). Watching, from the Edge of Extinction. Yale University Press. p. preface x. ISBN 978-0-300-08469-6. Retrieved 30 May 2017. <a href="978-0-300-08469-6" target="_blank">978-0-300-08469-6</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>Novacek, Michael J. (8 November 2014). "Prehistory's Brilliant Future". New York Times. Retrieved 2014-12-25. <a href="https://www.nytimes.com/2014/11/09/opinion/sunday/prehistorys-brilliant-future.html" target="_blank">https://www.nytimes.com/2014/11/09/opinion/sunday/prehistorys-brilliant-future.html</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Are we alone in the universe?". NASA. March 1, 2022. Retrieved July 12, 2022. <a href="https://exoplanets.nasa.gov/search-for-life/can-we-find-life/" target="_blank">https://exoplanets.nasa.gov/search-for-life/can-we-find-life/</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> </ol>