26

Do organisms exist that are able to live indefinitely if they are not killed by external factors?

Under external factors I would consider things like predators and natural disaster but not illness by bacteria for example.

De Novo
  • 8,791
  • 1
  • 24
  • 45
Steven Roose
  • 1,393
  • 1
  • 12
  • 17
  • 2
    See http://biology.stackexchange.com/questions/6884/why-is-the-hydra-biologically-immortal – kmm May 02 '13 at 12:21
  • the biggest issues for immortality are internal factors - senescence (aging) is a planned death on a cellular and organismal level. the above referenced question is a pretty good review of answers. Aubrey de Grey is another good google term to understand proposals which may reverse aging. – shigeta May 02 '13 at 13:18
  • 3
    If you're referring to the elves of Middle Earth, I'm sorry no they do not exist. – Daniel Standage May 02 '13 at 13:20
  • I'm not, I was more looking after some bacteria species. Or maybe some sort of tardigrade.. – Steven Roose May 02 '13 at 15:49
  • Umm, that was supposed to be a joke... – Daniel Standage May 03 '13 at 00:19
  • I find your distinction between internal and external factors a bit arbitrary. What is your motivation for excluding bacterial infections as external cause of death?

    You might be interested in what happens in plants. Here is an example, where the plants get cloned and seem to be able to do this for an indefinite amount of time, but they loose their fertility: http://www.wired.com/wiredscience/2010/08/aspen-immortality/

     – bli May 03 '13 at 09:48
  • I think a lot of this answer hinges on the (artificial) choice of how to distinguish what constitutes an "organism" versus a collection of organisms. – R.. GitHub STOP HELPING ICE May 26 '13 at 21:06
  • Duplicate: see this http://biology.stackexchange.com/questions/6884/why-is-the-hydra-biologically-immortal and http://biology.stackexchange.com/questions/7010/is-there-any-kind-of-immortality-in-plants – rg255 Jul 08 '13 at 19:43
  • 1
    @StevenRoose see this book (http://books.google.co.uk/books?id=4wEspn9gUdoC&pg=PA109&lpg=PA109&dq=extrinsic+causes+of+death&source=bl&ots=Cj-gAk94ZC&sig=wfo9x9I614_TyYEyGa6kUaUoZS8&hl=en&sa=X&ei=HTDbUfrIMsfXtAbasYCYDQ&ved=0CEsQ6AEwAw#v=onepage&q=extrinsic%20causes%20of%20death&f=false) page 108. It defines extrinsic and intrinsic causes of death - as someone studying aging and lifespan I can tell you these are standard definitions and bacterial/viral infections are considered extrinsic. – rg255 Jul 08 '13 at 21:36
  • 2
    The immortal jellyfish, Turritopsis dohrnii http://en.wikipedia.org/wiki/Turritopsis_dohrnii – Kevin May 16 '14 at 20:25
  • The most amazing thing about this is that if you own one of these creatures, than you can call it "My immortal". – Red Banana Feb 03 '19 at 17:12
  • hydra vulgaris & stuff i suggest to read "mortality patterns sugest lack of senescence in hydra" Daniel E. Martinez – Gupie Dziecko Feb 20 '19 at 22:00

4 Answers4

17

I now found this Wikipedia article on biological immortality. It's pretty much what I was looking for.

Wikipedia describes the phenomenon as follows:

Biological immortality refers to a stable or decreasing rate of mortality from cellular senescence as a function of chronological age. Various unicellular and multicellular species may achieve this state either throughout their existence or after living long enough. A biologically immortal living thing can still die from means other than senescence, such as through injury or disease.

It has a list of such organisms as well, consisting of

Addendum: This blog post takes a good look into the myth of lobster immortality. It seems to be as much a myth as the result of any substantial observation.

shigeta
  • 28,244
  • 2
  • 60
  • 120
Steven Roose
  • 1,393
  • 1
  • 12
  • 17
14

Yes. The Bristlecone Pine, Pinus longaeva, is one example. This species boasts the oldest individual living organisms, and also has been convincingly argued by Lanner and Connor (2001) to show no evidence of senescence.

While the Wikipedia page on Biological Immortality (as of June 2013) unfortunately ignores plants, the pages on Negligible Senescence and Longest-lived Organisms list many plant seeds, clonal groups, and individuals.

Oreotrephes
  • 5,799
  • 1
  • 29
  • 54
  • This is indeed a correct answer, as many organisms listed on other answers show some aging. The entire list of (presently 7) organisms, including P. longaeva, which do not show signs of senescence is given in a subsection of the reference AnAge database, which collects information on aging of every species: http://genomics.senescence.info/species/nonaging.php – tsttst Feb 21 '19 at 00:33
6

The immortal jellyfish (Turritopsis dohrnii) is capable of biological immortality.

enter image description here

It's one of few known species capable of reverting completely to a sexually immature, colonial polyp stage after having reached sexual maturity as a solitary (free-floating) individual (called a medusa).

Theoretically, this process can go on indefinitely, effectively rendering the jellyfish biologically immortal

enter image description here

Image source: Piraino et. al. 1996

Citations

Piraino, Stefano, et al. 1996. "Reversing the life cycle: medusae transforming into polyps and cell transdifferentiation in Turritopsis nutricula (Cnidaria, Hydrozoa)." The Biological Bulletin 190(3): 302-312.

theforestecologist
  • 29,867
  • 10
  • 122
  • 204
4

Examples found in plant world also- especially those with high vegetative reproduction and regeneration property.

https://en.wikipedia.org/wiki/The_Great_Banyan

Great banyan tree in Indian botanic garden Great banyan tree in Indian botanic garden

Always Confused
  • 2,671
  • 2
  • 25
  • 50