Fissiparie

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Fissiparie describes the ability of certain animals to generate a new organism from severed body parts . This term is best known in connection with the asexual reproduction of some echinoderms . For example, starfish can multiply by pushing their arms off, with a new starfish emerging from each arm.

particularities

Fissiparie as a form of reproduction is known in only 26 of the approximately 1600 described species of starfish , although the mechanism differs greatly between the species. In particular, smaller specimens in a population seem to use this form of reproduction. It has been observed that reproduction through fissiparia occurs mainly under extreme environmental conditions, such as extreme temperature , lack of oxygen, or increased salinity ( K + ). Experimentally , Fissiparie can e.g. B. be triggered by cutting the nerve rings in two places or by electrical current . Natural Fissiparie was observed in one variety of Luidia even in the larval stage.

Except for starfish is Fissiparie yet known in other echinoderms : At sea lilies , sea urchins , sea cucumbers and brittle stars . In addition, Fissiparie has been described in many invertebrates , for example in moss animals , cnidarians , articulated worms , belt worms , acorn worms ( Hemichordata ), horseshoe worms , injection worms and flatworms .

In protozoa , this form of reproduction through regeneration is also known as schizotomy or schizogony .

swell

  1. ↑ Starfish fissiparie
  2. ↑ a b Wilfried Westheide & Reinhard Rieger (eds.): Special Zoology. Part 1. Protozoa and invertebrates , 2nd edition. Edition, Spectrum Akad. Verl., Heidelberg u. a. 2007, ISBN 9783827415752 , p. 976.
  3. ↑ Fu Shiang Chia & Charles W. Walker: Echinodermata: Asteroidea . In: Arthur C. Giese, John S. Pearse & Vicky B. Pearse (Eds.): Reproduction of Marine Invertebrates, Vol. VI. Echinoderms and Lophophorates ( English ). Boxwood Press, Pacific Grove, CA 1991, ISBN 0-940168-09-X , pp. 301-353.
  4. ↑ Arthur C. Giese & John S. Pearse (Eds.): Reproduction of Marine Invertebrates, Vol. I – VI ( English ). Boxwood Press, Pacific Grove, CA 1974-1991, ISBN 0-940168-09-X .