In article <2s2c6h$hj1 at crocus.csv.warwick.ac.uk> cuhes at csv.warwick.ac.uk (Malcolm McMahon) writes:
>>I don't think the entropy idea really holds water because errors would
>accumulate from one generation to the next as quickly as from one
>mitosis to the next. Just as lethal mutations are selected out in a
>species so they would be selected out in a group of cells.
This is a very good argument. One would think that deleterious
but silent mutations could accumulate from one generation to
another until an entire species is wiped out. But that does not
happen.
>The death clock argument is the first suggested mechanism of aging that
>has ever made sense to me because it explains why there are no imortal
>mutants - they die of cancer before we notice they are immortal.
But using the same argument as above. There must be a way to
prevent cancer in old age. A single cell can develop into an
organism without any problems, why would an adult organism
eventually develop cancer?
>Looking at the way that anomolous longevity seems to have quickly evolved
>in humans as soon as we found a use for grandparents suggests that it's
>actually rather easy for evolution to produce longevity (experiments
>with drosophelia show the same thing). To me this clearly points to
>aging being a "deliberate" mechanism rather than some wear and tear thing.
>Malcolm
I don't know about aging being deliberate, but perhaps there are
some deleterious genes or aging genes that is present in our
DNA. There's no selection for longevity genes since as long as
an organsim reaches the reproductive age, it has survived well
in the evolutionary sense.
-fm
