Is death a product of evolution

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Why do bodies grow old and die? Would it not be evolutionarily 'stable' to live longer and have more children and look after them and have more children and so on and so on?

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You should read about r/K selection theory as it deals directly with this question. An r strategist live hard and die young (much like a rockstar). They will use up all the energy they have acquired to produce as many offspring in the shortest perioud of time. Think about annual flower plants. They grow, flower, produce seeds, and die. Then the next year it is the same t hing.A K strategist lives long and conservatively. They spend more time producing quality young and nurturing their young. They usually inhabit much more stable environments.Here is a link to the wikipedia article on r/K strategies
r/K selection theory - WikipediaAs for why we die of old age, it is the same reason why we have to buy new computers and cars eventually. The components wear out. I don't know if there was a study for this to see what strategy would be most beneficial, but from observations from life seems that what evolved was a mechanism for reproduction rather than repair. The 2nd law of thermodynamics is not going anywhere and the parts that make up our bodies are going to wear out.As a side note, I always enjoyed though experiments of what would happen if we were not to die or live an extremely long life. I like to think in terms of morality rather than evolution because you would wonder what our thoughts of killing other non-mortal organisms would be like.Edited by mobio, : added link

There was a study done, which I have forgotten the name, that shows that as bacteria divide the newly synthesized components will have a higher probablity of going into the same daughter cell, and the older components will go in the other daughter cell. This would create a cell that has all new parts, while another cell would have the older parts. In the study it showed that over time the cell that contains the older parts is less fit than the cell with the newer parts.

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Historically, ageing was first likened to 'wear and tear': Our bodies get weak for the same reason that a knife gets dull or metal rusts. But this idea was discredited in the 19th century when the second law of thermodynamics was formalized. Entropy (disorder) must increase inevitably within a closed system, but living beings are not closed systems. In fact, it is a defining feature of life that we take in free energy from the environment and unload our entropy as waste. Living systems routinely repair themselves, and, in fact, can build themselves up from seed. There is no thermodynamic necessity for senescence. (Nevertheless, the idea of 'wearing out' has so much intuitive appeal that even experts will lapse into thinking that way at times.)

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I would disagree with that statement. It assumes that the entire organism is an open system. Just because living cells can repair some decaying cellular components does not mean all cellular components are repaired.Multicellular organisms can compartmentalize the effect of degradation on them. Having the arm fall off of an organism due to some accident will not affect the gametes and thus reproduction, but mutations that will occur in the DNA during spermatogenesis or in the eggs of females over their lifetime could make them sterile.Unicellular organisms have been shown to compartmentalize their degrading cellular components by specifically segregating the older components into one daughter cell and placing the newly syntesized components into another daughter cell. It has been shown that the cells that have the older components are less fit than the cells with the newer components. I will try to find the paper of the experiment.I agree that apoptosis and other programmed cell death has an impact on cell life and there may be a limit to age, but to disregard environmental impact would be a fallacy.

This is the paper I was speaking about. It is an amazing paper.Paper by Watve M, Parab S, Jogdand P, and Keni SHere is part of the abstract. This paper shows that while immortality can exists, it exits in E. coli as a strategy of segregating new cellular components from old components.