Sebastian LaFleur
The Scope
Gallente Federation
4
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Posted - 2011.12.19 23:47:00 -
[1] - Quote
Eternum Praetorian wrote:We do not die because we have to, we die because we evolved to do so. If you work in the medical field you will understand what happens to a large portion of the human population as they age. Even if our cells were not hard coded to stop dividing, each and every human being would amass a wealth of their own personal body changing events.
While you are correct that "we do not die because we have to", I have to disagree with you in that we have evolved to do so. There is no incentive for evolution to develop organisms that have to die. Take oxygen for example. Oxygen is a poison. Because of the high reactivity of oxygen it will lead to, if not countered, degradation of cellular functions and eventually to death of the cell. But precisely because of this quality of oxygen, it has been advantageous for organisms to evolve to use it in energy metabolism by the reduction of oxygen with electrons from carbohydrates. This produces much more energy in the form of ATP (or adenosine triphosphate) than using some other element in reduction like anoxygenic bacteria do. To counter the harmful effects of oxygen, oxygen using organisms have evolved several mechanisms to transform the harmful oxygen radicals to less harmful forms. But eventually oxygen will kill us (...indirectly).
Also, due to the nature of DNA replication, the DNA strands get shorter and shorter after each replication and this will eventually lead to degradation of the genetic code, loss of cellular functions and programmed cell death (or apoptosis). To counter this, organisms with linear chromosomes have evolved to include telomerase sequences to the ends of the DNA strands. These sequences do not code of any function, but allow the cell to maintain its functions longer. Incidentally, cancer cells develop when the programmed cell death is not functioning, which allows the cancer cells to replicate indefinitely. Cancer cells also have the ability to regenerate the telomerase sequences, thus extending the cells ability to replicate.
So, we die because of the accumulated effects of genetic degradation and diseases, not because we have evolved to die (since the ability to counter the harmful effects of living is there. It just isn't good enough to keep organisms alive forever.)
Quote:Biology has two choices...
1. Create a functionality that is capable of repairing and restoring itself indefinably
2. Create organic function that commits seppuku after it has created the next generation that starts from scratch.
Aspect 1. cannot exist because our biological make up is simply not intelligent enough to do this.
There is a species of jellyfish, Turritopsis nutricula, in which an individual (in theory) can live forever. This is because it has the ability to revert from sexually mature form to juvenile polyp form and start the development towards sexually mature form again. However, the individuals die because of predation and diseases etc., so in practice there probably isn't any immortal individuals. But in sheltered environments the potential is there, so there is no biological barrier for living forever.
Quote:Aspect 2. by hard coding biology to destroy itself after so many cellular divisions, evolution ensures that a species remains uniform by constantly starting from scratch, over and over again, in the next generation.
I see a misunderstanding of the mechanisms of evolution here. Evolution can not produce adaptations to future environments. Saying that organisms have evolved to die to "ensure that a species remains uniform by constantly starting from scratch" is like saying that evolution has retained functional gills in terrestrial animals just in case there should be a flood happening in the future...
My video projects thread: https://forums.eveonline.com/default.aspx?g=posts&t=33270
My YouTube channel: https://www.youtube.com/user/SebastianLaFleur
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