Aging: Evolution's Unexpected Result

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Discussion Overview

The discussion centers on the concept of aging as an evolutionary phenomenon, exploring its implications and underlying mechanisms. Participants examine whether aging is a product of evolutionary processes or an external factor, and they engage with various theories related to aging and its effects on adaptation.

Discussion Character

  • Debate/contested
  • Exploratory
  • Technical explanation

Main Points Raised

  • Some participants propose that aging is not selected by evolution but is an inevitable outcome of evolutionary processes, with mechanisms behind aging becoming clearer through research.
  • One participant suggests that while organisms typically die from external factors before aging becomes significant, aging may still provide a bias favoring younger individuals, potentially accelerating adaptation.
  • Another participant references the theories of Medawar, Williams, and Kirkwood, arguing that aging exists due to weak selective pressure against negative genetic effects that manifest later in life.
  • There is a contention regarding the nature of aging, with one participant asserting that recent studies indicate cell death is controlled, opposing the notion that aging is a random and uncontrolled process.
  • Participants express a desire for feedback on the article discussing aging, indicating a willingness to revise and improve the work based on community input.

Areas of Agreement / Disagreement

Participants express differing views on the mechanisms and implications of aging, with no consensus reached on whether aging is a random process or a controlled phenomenon. The discussion remains unresolved with multiple competing perspectives presented.

Contextual Notes

Some arguments depend on specific definitions of aging and the selective pressures involved, which may not be universally agreed upon. The discussion also highlights the complexity of aging as a biological process, with various factors contributing to its understanding.

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Aging is a result of evolution, not something selected by evolution, but something outside the selective powers of evolution. As research uncovers more and more about the mechanisms behind aging the exact nature of this fact is being realized more and more.

http://physicspost.com/articles.php?articleId=166
 
Last edited:
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Has anyone who has read this article got any feedback for me? I intended on revising the article and writting a more publically accesible version (this version being an actual Uni Assignment). Any thoughts? Does anyone care?
 
The article is very good... Though you might do well to separate it out a bit. Eg. 1 chapter on the process of aging, and one on implications.

But I don't altogether agree with some of your conclusions...

In a typical natural environment organisms die through predation, accident, starvation, infection and other such events long before aging becomes a factor [20].
True, but we have to see age as not a cut-off point, but as a gradual crawl. Though few may die actually of aging, they do weaken. Hence it is possible to surmise that the aging process gives an inherent bias in favour of younger individuals, and may hence work to accelerate adaptation, giving new characteristics a small edge, as so some processes of aging can be "useful".
 
Originally posted by FZ+
True, but we have to see age as not a cut-off point, but as a gradual crawl. Though few may die actually of aging, they do weaken. Hence it is possible to surmise that the aging process gives an inherent bias in favour of younger individuals, and may hence work to accelerate adaptation, giving new characteristics a small edge, as so some processes of aging can be "useful".
The point of that observation though, is to explain why aging exists at all. In a world where there was no aging phenotypes, organisms would eventually die through those sort of events. Because of that, there is no selective pressure (or a very weak selective pressure) to stop negative genetic effects which only occur later in life.

This particular conclusion is not my own anyway, it's just one tha I believe to be very reasonable. It is the theory of Medawar, Williams and also Kirkwood. The best paper to read on it is Williams' (in the references). Very easy to read and very very insightful. His paper is the origin of Antagonistic Pleiotropy theory...and yeah.. um, i'll stop ranting.

anyway, what other conclusions do you disagree with? (Of all the discussions I get into on PF, none can interest me more than this one, in case you don't yet know, this is what I intend to spend my life doing, so if you can find any faults with anything I say/think here, this is more important than just about anything to me *Nodz*
 
anyway, what other conclusions do you disagree with?
Not much.

But I'll go out on a limb and oppose this:
complex side effects piled on top of each other in a somewhat random uncontrolled way
From recent studies, even cell death has been shown to be very much controlled. So, while Aging may well be a complex mixture of effects, I don't think it is really random or uncontrolled.

Bodies don't play dice? :wink:
 
Originally posted by FZ+
Not much.

But I'll go out on a limb and oppose this:

From recent studies, even cell death has been shown to be very much controlled. So, while Aging may well be a complex mixture of effects, I don't think it is really random or uncontrolled.

Bodies don't play dice? :wink:

BUt the cell death you mention plays a functional role in multicellualr organisms. This is age related death, this is 'Oh my God something's wrong. Abort ship!' death.
 
Well... just stating an opinion. We shall see what future research brings, eh?
 

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