Outline of life forms

"Lifeform" redirects here. For other uses, see Lifeform (disambiguation).

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,[1][2] 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,[3] are extinct.[4][5]

Earth is the only celestial body known to harbor life forms. No form of extraterrestrial life has yet been discovered.[6]

  1. ^ "life form". World English Dictionary. Dictionary.com. 2009.
  2. ^ "life form". Online Oxford Dictionary of English. Oxford University Press. 2005. Archived from the original on 2011-08-11.
  3. ^ 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.
  4. ^ 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.
  5. ^ Novacek, Michael J. (8 November 2014). "Prehistory's Brilliant Future". New York Times. Retrieved 2014-12-25.
  6. ^ "Are we alone in the universe?". NASA. March 1, 2022. Retrieved July 12, 2022.