I watched a YouTube on aging and death, from an evolutionary standpoint.
Evolution seems to favor species that breed fast and young, flooding the environment with offspring, so that at least some will survive, and are not all eaten.
Then, after their reproductive years, they have less of a purpose. And the body starts to accumulate defects and mutations. But as long as the egg and sperm were good while young, this does not effect the next generation.
Now, scientists found organisms that regenerated. And sometimes cell colonies in labs never seemed to die out. Yet they later realized they were being contaminated with new cells, and the old cells were genetically programmed to die out.
It turns out chromosomes have caps called telomeres, that are snipped a little after each cell division. Eventually the cap is gone and the cell cannot divide.
The evolutionary logic seems to be that if cells were allowed to divide forever then cancers would pop up. People would live longer and die of cancer. So cell-lines not being immortal I suppose is a defense against cancer early in life before reproduction ends (since if we only got cancer after menopause, etc., it would not make a difference on our progeny we made in our youth). But I could be wrong on this logic. I forgot details and am reasoning through it now.
Of course, societies would support old people who cannot provide for themselves (not hunt, farm, gather, etc.). But there may be an evolutionary benefit of keeping the elderly around since they assist in raising and educating their grandchildren.
I wonder what will happen if science figures out how to rejuvenate our body decline yet keep cancer in check. What if we all lived a thousand years? (We still could die from accidents, infections, and violence, of course).
Could society function? Would there be enough young people to provide for the old? Could the old be made to stay young? Or would a person just be young for a few decades, then old for centuries? Would people want to feel like a 90 year old for 900 years? Would we get sick of life and our dependency? Could robots fill the gap? Would they decide we are a waste and eliminate us?
At least we can live on in our artifacts. But it it is a one way conversation. Unless we emulate the departed with AI. It is already happening on YouTube!
There is also the concept that the purpose of life is to pass on genes. We are just necessary, yet disposable hosts for this thread. Life has lasted billions of years. Individual organisms mean nothing in the grand scheme. It makes one feel small.
