Outline of life forms

{{Short description|Overview of and topical guide to life forms}}

{{redirect|Lifeform}}

{{Life timeline}}

The following outline is provided as an overview of and topical guide to life forms:

A life form (also spelled life-form or lifeform) is an entity that is living,{{cite web |title=life form |url=http://dictionary.reference.com/browse/life+form |publisher=Dictionary.com |work=World English Dictionary |date=2009}}{{cite web |title=life form |url=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 |archive-url=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 |url-status=dead |archive-date=2011-08-11 |publisher=Oxford University Press |work=Online Oxford Dictionary of English |date=2005}} such as plants (flora), animals (fauna), and fungi (funga). It is estimated that more than 99% of all species that ever existed on Earth, amounting to over five billion species,{{cite book |editor1=Kunin, W.E. |editor2=Gaston, Kevin |title=The Biology of Rarity: Causes and consequences of rare—common differences

|url=https://books.google.com/books?id=4LHnCAAAQBAJ&pg=PA110|date=31 December 1996 |isbn=978-0412633805 |access-date=26 May 2015}} are extinct.{{cite book |last1=Stearns |first1=Beverly Peterson |last2=Stearns |first2=S. C. |last3=Stearns |first3=Stephen C. |title=Watching, from the Edge of Extinction |url=https://books.google.com/books?id=0BHeC-tXIB4C&q=99+percent |year=2000 |publisher=Yale University Press |isbn=978-0-300-08469-6|page=preface x |access-date=30 May 2017}}{{cite news |last=Novacek |first=Michael J. |title=Prehistory's Brilliant Future |url=https://www.nytimes.com/2014/11/09/opinion/sunday/prehistorys-brilliant-future.html |date=8 November 2014 |work=New York Times |access-date=2014-12-25}}

Earth is the only celestial body known to harbor life forms. No form of extraterrestrial life has yet been discovered.{{cite web |url= https://exoplanets.nasa.gov/search-for-life/can-we-find-life/|title= Are we alone in the universe?|author= |date= March 1, 2022|publisher= NASA|accessdate=July 12, 2022}}

Archaea

Bacteria

Eukaryote

See also

References

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