Turritopsis dohrnii

Immortal jellyfish
Turritopsis dohrnii medusa
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Cnidaria
Class: Hydrozoa
Order: Anthoathecata
Family: Oceaniidae
Genus: Turritopsis
Species:
T. dohrnii
Binomial name
Turritopsis dohrnii
(Weismann, 1883)[1]
Synonyms[1]
  • Cytaeis polystyla Will, 1844
  • Dendroclava dohrnii Weismann, 1883

Turritopsis dohrnii, also known as the immortal jellyfish, is a species of small, biologically immortal jellyfish[2][3] found worldwide in temperate to tropic waters. It is one of the few known cases of animals capable of reverting completely to a sexually immature, colonial stage after having reached sexual maturity as a solitary individual. Others include the jellyfish Laodicea undulata[4] and species of the genus Aurelia.[5]

Like most other hydrozoans, T. dohrnii begin their lives as tiny, free-swimming larvae known as planulae. As a planula settles down, it gives rise to a colony of polyps that are attached to the sea floor. All the polyps and jellyfish arising from a single planula are genetically identical clones.[6] The polyps form into an extensively branched form, which is not commonly seen in most jellyfish. Jellyfish, also known as medusae, then bud off these polyps and continue their life in a free-swimming form, eventually becoming sexually mature. When sexually mature, they have been known to prey on other jellyfish species at a rapid pace. If the T. dohrnii jellyfish is exposed to environmental stress, physical assault, or is sick or old, it can revert to the polyp stage, forming a new polyp colony.[7] It does this through the cell development process of transdifferentiation, which alters the differentiated state of the cells and transforms them into new types of cells.

Theoretically, this process can go on indefinitely, effectively rendering the jellyfish biologically immortal,[3][8] although in practice individuals can still die. In nature, most Turritopsis dohrnii are likely to succumb to predation or disease in the medusa stage without reverting to the polyp form.[9]

The capability of biological immortality with no maximum lifespan makes T. dohrnii an important target of basic biological aging and pharmaceutical research.[10]

  1. ^ a b Schuchert P, ed. (2012). "Turritopsis dorhnii (Weissmann, 1883)". World Hydrozoa database. World Register of Marine Species. Retrieved November 29, 2012.
  2. ^ Bavestrello, Giorgio; Christian Sommer; Michele Sarà (1992). "Bi-directional conversion in Turritopsis nutricula (Hydrozoa)". Scientia Marina. 56 (2–3): 137–140.
  3. ^ a b Piraino, Stefano; F. Boero; B. Aeschbach; V. Schmid (1996). "Reversing the life cycle: medusae transforming into polyps and cell transdifferentiation in Turritopsis nutricula (Cnidaria, Hydrozoa)". Biological Bulletin. 190 (3): 302–312. doi:10.2307/1543022. JSTOR 1543022. PMID 29227703.
  4. ^ De Vito; et al. (2006). "Evidence of reverse development in Leptomedusae (Cnidaria, Hydrozoa): the case of Laodicea undulata (Forbes and Goodsir 1851)". Marine Biology. 149 (2): 339–346. Bibcode:2006MarBi.149..339D. doi:10.1007/s00227-005-0182-3. S2CID 84325535.
  5. ^ He; et al. (2015-12-21). "Life Cycle Reversal in Aurelia sp.1 (Cnidaria, Scyphozoa)". PLOS ONE. 10 (12): e0145314. Bibcode:2015PLoSO..1045314H. doi:10.1371/journal.pone.0145314. PMC 4687044. PMID 26690755.
  6. ^ "Jellyfish and Comb Jellies | Smithsonian Ocean". ocean.si.edu. 30 April 2018. Retrieved 2020-10-19.
  7. ^ Cite error: The named reference nytm was invoked but never defined (see the help page).
  8. ^ Gilbert, Scott F. (2006). "Cheating Death: The Immortal Life Cycle of Turritopsis". Archived from the original on 2010-04-02. Retrieved 2009-03-22.
  9. ^ Ker Than (January 29, 2009). ""Immortal" Jellyfish Swarm World's Oceans". National Geographic News. Archived from the original on February 2, 2009. Retrieved 2010-06-16.
  10. ^ Cite error: The named reference :0 was invoked but never defined (see the help page).