Senescence
rating: 0+x

Basic Information

Senescence is a technical term that means roughly "death by old age", or refers to the process of breaking down as you get older. Several theories have been proposed to explain the aging process, ranging from wear and tear, to chemical and genetic damage.

One of the most interesting observations in relation to Senescence has to do with Telomeres. For the majority of animals (and the majority of cells), as cells reproduce, their genetic telomeres become shorter. Eventually, this results in the cell no longer being able to replicate itself, which may be the primary cause of aging and senescence. Why is that interesting? Because some animals don't have this problem.

  • The Hydra, a tiny water animal no more than a few millimetres long, appears to not experience senescence at all, or else so slowly it has yet to be observed.
  • Leach's Storm-petrel, a type of bird, actually grows telomeres over time, meaning it will never die of old age.
  • Turritopsis Nutricula is a form of Jellyfish that reverts to it's juvenile polyp stage after sexual reproduction. It gets it on, turns back into a kid, grows up, gets it on, turns into a kid, grows up, gets it on, turns into a kid, etc.

All three of those species have achieved Biological Immortality (probably). They can still experience death via starvation, predation, etc., but will never die of old age. Other species have Negligible Senescence (extremely reduced impact of aging), such as certain types of turtle or rockfish.

Conversely a number of species - often invertebrates - have processes whereby one or both genders1 undergo rapid senescence following reproduction. Built in senescence - either time based or triggered by some environmental factor - may also be a feature for bioroids or other gengineered creatures to limit their ability to operate as an independent party.

There are also some types of cells that are immune to Senescence. Part of what makes Cancer so hard to fight is that cancer cells do not die of old age. Whereas normal cells fail all the time, cancer cells have to be killed.

Drugs (or magic) that prevent, retard, or undo aging are called anti-agathics.

Sources

Game and Story Use

  • A Mad Scientist working on the issue of Senescence discovers a way to protect Telomeres, creating a limited form of Immortality.
    • If he keeps it to himself, he may become a Time Abyss after several millenia.
    • If he shares it with the world, there'll be short-term benefits, but eventually it may lead to a Malthusian Catastrophe.
  • An Alien species might have a life cycle similar to the Turritopsis Nutricula, being immortal and going through alternating stages of adulthood and childhood. If this species is intelligent / sentient, the resulting psychology could be complicated.
  • Many fantasy settings allow resurrection of some kind - but most of them still assume senescence. That is to say, the body is revived to the same age as it was before death, and the person will still die of old age eventually, no matter how often he is resurrected. But what if this wasn't true? What if the body is restored to its prime as it returns from death?
    • In that case, there will likely be a strong social divide between those who are able to afford resurrection, and those who aren't - the former are effectively immortal.
  • The bioroids in Blade Runner were troubled by a rapid senescence function.
Unless otherwise stated, the content of this page is licensed under Creative Commons Attribution-ShareAlike 3.0 License