ArtsAutosBooksBusinessEducationEntertainmentFamilyFashionFoodGamesGenderHealthHolidaysHomeHubPagesPersonal FinancePetsPoliticsReligionSportsTechnologyTravel

What is Negligible Senescence

Updated on July 26, 2013
A large Great Basin Bristlecone Pine Pinus longaeva, showing both live and dead sections, and streaked grain colors on broad trunk. It is purported to have a lifespan of 4,713 years.
A large Great Basin Bristlecone Pine Pinus longaeva, showing both live and dead sections, and streaked grain colors on broad trunk. It is purported to have a lifespan of 4,713 years. | Source
Aldabra giant tortoise = Aldabrachelys gigantea = Dipsochelys dussumieri
Aldabra giant tortoise = Aldabrachelys gigantea = Dipsochelys dussumieri | Source

Definition of Senescence

In biological terms, senescence refers to the process of aging. It includes accumulative changes which disrupt metabolism resulting in the deterioration of the organism and eventually death. Senescence occurs at two levels:

  1. cellular senescence whereby normal diploid cells lose the ability to divide
  2. organismal senescence involves the aging of the whole organism characterised by
  • the declining ability to respond to stress,
  • decreased reproductive capability,
  • decreased strength and mobility,
  • reduced sensory acuity
  • increased homeostatic imbalance,
  • and increased risk of age-related diseases and associated death rate.

Immortality is a long shot, I admit. But somebody has to be first. — Bill Cosby

Definition Of Negligible Senescence

The term 'negligible senescence' was first used in the 1990s by professor Caleb Finch to describe organisms like lobsters and hydra which showed no signs of senescence as they aged. Negligible senescence refers to a lack of symptoms of aging in a few select animals. These animals:

  1. do not have measurable reductions in reproductive capacities with age;
  2. do not have measurable functional decline with age including strength and mobility;
  3. do not have increased death rate with age.

There is strong scientific grounds to suggest that humans of advanced ages are negligibly senescent.

Just how organisms and some humans that exhibit negilgible senescence accomplish the feat of staying 'young' forever is a hot topic for longevity scientists. If the secret to their longevity and anti-aging could be discovered it could provide a stepping stone for research into extending human longevity by technological means.

Organisms Thought To Be Negligibly Senescent

Scientific Name
Maximum Observed Life Span (years)
Aldabra Giant Tortoise
Geochelone gigantea
Antarctic sponge
Stylocordyla chupachups
est 1550
Blanding's Turtle
Emydoi dea blandingii
Eastern Box Turtle
Terrapene carolina
Fresh water pearl mussel
Margaritifera margaritifera
Geoduck saltwater clam
Panopea generosa
Great Basin Bristlecone Pine
Pinus longaeva
biologically immortal
Immortal jellyfish
Turritopsis nutricula
biologically immortal
Cyprinus carpio
Lamellibrachia tube worms
Lamellibrachia luymesi
Homarus americanus
100 years
Ocean Quahog clam
Arctica islandica
Proteus anguinuus
Painted Turtle
Chrysemys picta
Red Sea Urchin
Strongylacentratus franciscanus
Rough-eyed rockfish
Sebastes aleutianus
Sea anenomes
White Sturgeon
Acipenser transmontanus, acipenser

Do Creatures Displaying Negligible Senescence Die?

Creature exhibiting negligible senescence do not age and therefore do not die of age related conditions. These creatures do die however but from the following:

  • predation
  • habitat changes
  • accidents
  • starvation
  • adverse environmental conditions
  • disease

If there was a way of creating the condition of Negligible Senescence in humans would you take the treatment to achieve immortality?

See results

What Causes Aging In Humans And Other Organisms

Most biologists attribute ageing or senescence in humans and other animals to 'telomeres'. Telomeres are the tiny caps on the ends of every chromosome that protect DNA from being corrupted. However, for every cell division, these telomeres become shorter. For each shortening, the cell duplicates itself a little worse than before. When they have become too short, the cell can no longer divide, a phenomenon known as the Hayflick Limit. The decay of telomeres is the biological root of death from old age. In many organisms, the enzyme telomerase maintains the telomeres during cell division. Once the organism reaches maturity, this enzyme stops functioning and the ageing process officially begins.

The Hayflick Limit can have a number of consequences leading to ageing in organisms:

  • Mechanical senescence becomes an issue with many as when cells no longer divide, tissue cannot regenerate leading to wearing out of body parts such as feeding apparatus (teeth, mouth parts) and other body parts such as the gut and muscle tissue.
  • Hormone-driven processes break down which reduce sexual drive, reduce reproductive processes, decrease the desire to feed and cause disease such as arthritis, arteriosclerosis and others.

Click thumbnail to view full-size
 Red rockfish Sebastes aleutianus Ocean Quahog clam Stułbia, Hydra
 Red rockfish Sebastes aleutianus
Red rockfish Sebastes aleutianus | Source
Ocean Quahog clam
Ocean Quahog clam | Source
 Stułbia, Hydra
Stułbia, Hydra | Source

Theories Explaining Negligible Senescence

Natural selection logically would not favor negligible senescence in most circumstances. Reproducing favorable genotypes leads to the reproductive individuals being favored. Once they have accomplished this feat, post-reproductive organisms become redundant and utilize resources to the detriment of reproductive and pre-reproductive individuals. There are, however, cases where negligible senescence is a favorable attribute.

1. Organisms that live in stable but crowded conditions favor longevity.

  • In this condition new opportunities for space for mature individuals arise infrequently.
  • Organisms that outlive their neighbors provide growing space for their own seedlings or larvae when they die.
  • The Bristle cone pine and the Arctic quahog are two species which live in this type of environment and appear to use this strategy.

2. Planarians or flatworms have the capability to perpetually regenerate and thus, exhibit biological immortality.

  • They are able to restore any damaged organ, including their brains.
  • This capability gives them virtual immortality baring predation, accident or lack of resources.
  • An equivalent enzyme to telomerase is present in asexual flatworms and is responsible for the flatworms 'immortality'.
  • This enzyme does not appear to degrade at any point in the flatworm's life cycle thus, their telomeres remain in perfect condition allowing for their perpetual regeneration.

3. In general, asexual reproduction tends to lead to longer lifespans.

4. Organisms with extremely high infant mortality may favor negligible senescence for individuals reaching maturity to ensure longer reproductive capabilities for the few survivors.

5. Organisms such as the worm, Lamellibracia grow in nutrient poor environments. They have a slower growth rate and thus reach the Hayflick Limit at a much slower pace resulting in significantly longer lifespans.

6. Some organisms such as the Walleye have significantly longer lifespans when their habitat is in colder waters.

  • For the Walleye, they experience a five fold increase in longevity in colder waters.
  • Lower temperatures mean organisms reach maturity at a much slower rate.
  • They reach the Hayflick Limit at a delayed rate greatly slowing the onset of age related deterioration.

7. Molting in crustaceans, such as the Lobster, replaces hard tissue, reducing wear and tear and thus, results in a longer life span.

 Diagram depicting the approaches to medically treating aging. "[The] arrows with flat heads are a notation used in the literature of gene expression and gene regulation, and they mean "inhibits". Thus, geriatrics is the attempt to stop damage from c
Diagram depicting the approaches to medically treating aging. "[The] arrows with flat heads are a notation used in the literature of gene expression and gene regulation, and they mean "inhibits". Thus, geriatrics is the attempt to stop damage from c | Source

Resources Used

de Magalhães, PhD, João Pedro. Some Animals Age, Others May Not. 2012

programmed aging. Negligible senescence. 2010

Wilkins, Alasdair. Negligible Senescence These immortal flatworms regenerate like real lifetime Lords. February 28, 2012..

Treating Senescence By Technological Means

A number of scientist are exploring technological means of increasing human longevity by studying those creatures which display negligible senescence. English transhumanist, Aubrey De Grey founded the S.E.N.S or "Strategies for Engineered Negligible Senescence" in 2002. Through this foundation, De Grey researches medical strategies for increasing the human lifespan with the ultimate goal of providing human 'immortality' through technological means. At this point, research is still a long way from achieving this goal.

Physican Terry Grossman claims to have remedies he proposes will keep many clients alive to the 125 year limit he feels humans can now aspire to. One of his clients is Ray Kurtzweil, famous inventor and futurist.


    0 of 8192 characters used
    Post Comment

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      21 months ago from Ontario, Canada

      Wonder how I got on Periscope then. Glad you enjoyed the article. I'm on my own blog now at Science Alcove. I am making more of an effort to check back on this site more frequently. Thanks for the comment Glenn.

    • Glenn Stok profile image

      Glenn Stok 

      2 years ago from Long Island, NY

      It's interesting that if a particular species does not age, that they still will die from other causes that eventually are unavoidable. As time progresses, some disaster will occur, such as those examples that you have listed.

      I found your hub extremely interesting, and I learned a lot from you about the process of aging from a cellular level. You explain things very well.

      By the way, I found you on Periscope although I know you didn't do any scopes yet. I didn't either.

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      3 years ago from Ontario, Canada

      Cold-bloodedness means slower metabolism and does confer some benefits. There is more to life than just living longer I agree.

    • poetryman6969 profile image


      3 years ago

      I see a lot of slow creatures and a lot of lower order creatures. I wonder if there was a devolution pill that conferred immortality, would anyone take it?

    • Robin profile image

      Robin Edmondson 

      5 years ago from San Francisco

      Wow! That's fantastic and well deserved. Your science Hubs are so well done. Congratulations. :)

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      Thanks Robin. It was so great, I actually got to speak about my article to a grade 12 advanced biology class I am currently teaching during our molecular genetics unit. Glad you enjoyed it!

    • Robin profile image

      Robin Edmondson 

      5 years ago from San Francisco

      Teresa, this is so interesting. I had no idea there was an immortal jellyfish. Your Hubs always pique my interest. :)

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      You have a valid point Nettlemere. Our population has exploded enough. Humans living longer may only compound a very serious problem. However, I think we all would love to be able to grow old while remaining healthier! Thanks for stopping by and reading!

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      I am sure hoping for a cure to some of the age-related annoyances that are cropping up more frequently LOL! Thanks for stopping by and commenting shiningirisheyes!

    • Nettlemere profile image


      5 years ago from Burnley, Lancashire, UK

      well researched and evidenced. I hope they don't find the secret of eternal life or considerably longer life for humans though. I think we are living long enough as it is.

    • shiningirisheyes profile image

      Shining Irish Eyes 

      5 years ago from Upstate, New York

      A fine example of the fantastic and amazing results research can provide. Here's to encouraging the continuation and maybe we will be provided with life changing procedures within my lifetime.

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      billy, glad I can bring back old but good memories. Thanks again for the feedback. It is always so very much appreciated!

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      mperrottet, I am so thrilled you found my article interesting. I will have to check out your article on transhumanism. Thanks for the feedback and sharing!

    • billybuc profile image

      Bill Holland 

      5 years ago from Olympia, WA

      I love your hubs because they give me a chance to revisit things I once taught but haven't thought about in years. Well done, Teresa!

    • mperrottet profile image

      Margaret Perrottet 

      5 years ago from San Antonio, FL

      This is an absolutely fascinating, well written article. I found it interesting that humans at advanced ages may be negligibly senescent. I guess that means that if you can reach the age that negligible senescence occurs in good shape, you have a good chance of living on for a very long time. I wrote a hub on transhumanism, and I'm not surprised that this is an area that transhumanists are exploring. Wonderful hub, voted up and interesting.

    • Teresa Coppens profile imageAUTHOR

      Teresa Coppens 

      5 years ago from Ontario, Canada

      Theresa I will have to look into that further. Low temperatures and lack of nutrients seem to be two big factors accounting for slower maturation and thus longer lives both environments being abundant in the ocean. However, gravity may have more effect on ageing mechanisms and I'm not sure if that has even been looked into. Thanks for the ideas for further thought and so glad you enjoyed the topic!

    • phdast7 profile image

      Theresa Ast 

      5 years ago from Atlanta, Georgia

      What a fabulous phrase "Negligible Senescence" and what a fascinating article. I thoroughly enjoyed this. And of course I immediately noticed how many of the examples on your chart are ocean as opposed to land creatures. What do scientists make of that? How is the ocean a more conducive environment for longevity with minimal senescence? Greatly decreased effect of gravity? As our oceans become (sadly) more polluted, I wonder if this will change in any measurable way. Terrific Hub! Sharing. :)


    This website uses cookies

    As a user in the EEA, your approval is needed on a few things. To provide a better website experience, uses cookies (and other similar technologies) and may collect, process, and share personal data. Please choose which areas of our service you consent to our doing so.

    For more information on managing or withdrawing consents and how we handle data, visit our Privacy Policy at:

    Show Details
    HubPages Device IDThis is used to identify particular browsers or devices when the access the service, and is used for security reasons.
    LoginThis is necessary to sign in to the HubPages Service.
    Google RecaptchaThis is used to prevent bots and spam. (Privacy Policy)
    AkismetThis is used to detect comment spam. (Privacy Policy)
    HubPages Google AnalyticsThis is used to provide data on traffic to our website, all personally identifyable data is anonymized. (Privacy Policy)
    HubPages Traffic PixelThis is used to collect data on traffic to articles and other pages on our site. Unless you are signed in to a HubPages account, all personally identifiable information is anonymized.
    Amazon Web ServicesThis is a cloud services platform that we used to host our service. (Privacy Policy)
    CloudflareThis is a cloud CDN service that we use to efficiently deliver files required for our service to operate such as javascript, cascading style sheets, images, and videos. (Privacy Policy)
    Google Hosted LibrariesJavascript software libraries such as jQuery are loaded at endpoints on the or domains, for performance and efficiency reasons. (Privacy Policy)
    Google Custom SearchThis is feature allows you to search the site. (Privacy Policy)
    Google MapsSome articles have Google Maps embedded in them. (Privacy Policy)
    Google ChartsThis is used to display charts and graphs on articles and the author center. (Privacy Policy)
    Google AdSense Host APIThis service allows you to sign up for or associate a Google AdSense account with HubPages, so that you can earn money from ads on your articles. No data is shared unless you engage with this feature. (Privacy Policy)
    Google YouTubeSome articles have YouTube videos embedded in them. (Privacy Policy)
    VimeoSome articles have Vimeo videos embedded in them. (Privacy Policy)
    PaypalThis is used for a registered author who enrolls in the HubPages Earnings program and requests to be paid via PayPal. No data is shared with Paypal unless you engage with this feature. (Privacy Policy)
    Facebook LoginYou can use this to streamline signing up for, or signing in to your Hubpages account. No data is shared with Facebook unless you engage with this feature. (Privacy Policy)
    MavenThis supports the Maven widget and search functionality. (Privacy Policy)
    Google AdSenseThis is an ad network. (Privacy Policy)
    Google DoubleClickGoogle provides ad serving technology and runs an ad network. (Privacy Policy)
    Index ExchangeThis is an ad network. (Privacy Policy)
    SovrnThis is an ad network. (Privacy Policy)
    Facebook AdsThis is an ad network. (Privacy Policy)
    Amazon Unified Ad MarketplaceThis is an ad network. (Privacy Policy)
    AppNexusThis is an ad network. (Privacy Policy)
    OpenxThis is an ad network. (Privacy Policy)
    Rubicon ProjectThis is an ad network. (Privacy Policy)
    TripleLiftThis is an ad network. (Privacy Policy)
    Say MediaWe partner with Say Media to deliver ad campaigns on our sites. (Privacy Policy)
    Remarketing PixelsWe may use remarketing pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to advertise the HubPages Service to people that have visited our sites.
    Conversion Tracking PixelsWe may use conversion tracking pixels from advertising networks such as Google AdWords, Bing Ads, and Facebook in order to identify when an advertisement has successfully resulted in the desired action, such as signing up for the HubPages Service or publishing an article on the HubPages Service.
    Author Google AnalyticsThis is used to provide traffic data and reports to the authors of articles on the HubPages Service. (Privacy Policy)
    ComscoreComScore is a media measurement and analytics company providing marketing data and analytics to enterprises, media and advertising agencies, and publishers. Non-consent will result in ComScore only processing obfuscated personal data. (Privacy Policy)
    Amazon Tracking PixelSome articles display amazon products as part of the Amazon Affiliate program, this pixel provides traffic statistics for those products (Privacy Policy)