Pathfinder
Registered Senior Member
there is a very complex genetic control of aging involving interplay between a number of genes (not merely telomerase), all of which are working together to kill us after a certain period of time. We can influence some of the epigenetic and environmental aspects of the aging process, but we can’t escape the fact that we are genetically programmed to die.
Not exactly. First, there is no evidence that telomere shortening contributes to aging. Second, organisms in the wild do not die of aging, they die of extrinsic causes, thus there is no evolutionary pressure towards aging in one way or another. So aging cannot be programmed. Aging is just organisms wearing off.
there are 3 mechanism at work in our aging, homeostasis mechanism which were evolved to last only long enough, deleterious genes that will cause those homeostasis mechanism to fail after reproductive prime and finally the lack of homeostasis mechanism for indifferent survival.
We were built to last long enough to reach reproductive age and nothing more. There is no planned system failure, because there is no evolutionary pressure for that.
There are some cases of antagnositic pleiotropy in the body, that is a gene that is very useful in early life happens to become a burden when the organism lives long enough e.g. in captivity, but there is nothing planned about that. For example our stem cells cannot keep on replenishing our tissues indefinitely, becuse the p53, an anti tumor gene, suppresses proliferation.
if we were to live for thousands of years we would build up toxic metals like mercury in our body because of we lack of mechanism for removing them, we have nothing to protects us from several hundred to thousand of years of ingestion.
Young and healthy people can excrete heavy metals fast enough (yet its quite slow) so that no dangerous accumulation occurs in lower doses. When we get old and frail, the excretion becomes slower and slower, thus old people accumulate heavy metals in their body much easier.