The author is somewhat confusing aging and dying. Aging is a mechanism. It is there for (probably) many reasons. One of them is to protect against cancer, and therefore from dying. You either age or you get cancer.
If we find a way to not age and not get cancer, then we have (presumably) evolved.
I agree.
> "Evolution never leads to best-case scenario"
That is not true. It could lead to the most optimal solution.
> Saying "either you age or get cancer" is just... not correct
It is correct until we develop an alternative way that replaces the aging mechanism in cells.
Sure, it is better to neither age nor get cancer.
There is no such thing as "the most optimal solution". Optimality is a human imposition on the world. Fitness functions do not actually exist, they are merely a way for us to conceive of the operation of selection. Evolution is not performing gradient descent.
This comment supposes that aging protects cells against cancer; I think this presumption is based on the antitumor properties of telomeres, which impose the 'Hayflick limit' on cellular division.
It is presumed by humans that this mechanism may have some adaptive role in tumor suppression. However: this is not why it appeared (all eukaryotes have telomeres, even unicellular ones), so any antitumor properties are an ancillary benefit.
It is incorrect to assume it impute reason to evolution. It seems highly likely that aging rests close to the border of selective influence, and it is highly presumptive to imagine it is governed by consequence.
The cell has many ways to combat oncogenesis and when these protections fail, it tries to go into senescence (SIGTERM) or die(SIGKILL).
Nanobots that would replace damaged cells with new non-cancerous ones are not yet here.
[1] http://www.impactaging.com/papers/v2/n7/full/100178.html [2] http://www.nature.com/nrc/journal/v3/n1/full/nrc984.html [3] http://newscenter.lbl.gov/2008/12/02/cellular-senescence/
I did not know that. Is there a reading on this topic you recommend?
If the cell lived (selfishly), it could take down the whole organism with it and not reproduce.
Then we can get into primary aging (think of the SENS list of damage, internal mechanisms like mitochondrial damage and cross-link deposition) versus secondary aging (think of smoking and getting fat, things that increase the pace of damage accumulation), and further complexities after that. But the core definition of aging is very simple, and it is all about dying.
However, aging!=dying since aging can protect the whole organism (as opposed to individual cells) from dying and some would argue that it is there primarily to protect the organism from dying from cancer and for healthy reproduction.
If you age, you get cancer, eventually. Sometimes some other pathology gets you first but everyone is afflicted with every "aging disease" but we seem to only care about which one kills you first.
One of the reasons cells age is to not get cancer. The cells that age can still get cancer! And probably more likely to get cancer than young cells. But less likely than if they didn't go into senescence at all.