[ExI] Are Limited Lifespans An Evolutionary Adaptation?

[BillK]

On 18 June 2015 at 15:24, Anders Sandberg  wrote:
> I'm not convinced, I see far too much random sloppiness (a sign of lack of
> evolutionary pressure) underlying ageing rather than timer processes (where
> evolution would optimize a particular lifespan).
>
> Still, given the evolutionary heuristic
> (http://www.nickbostrom.com/evolution.pdf), if their theory was true then we
> should be really happy as transhumanists! Because then we would be in a
> fairly clear-cut case of evolution having different goals than us, and
> enhancements of ageing would be less likely to have nasty side effects. If
> ageing is just the result of evolution not caring, then there may also not
> be any inherently bad side effects of fixing it, but we have far less reason
> to think there are simple underlying causes we can fix.
>
> So I doubt their theory, but I would be happy to be disproven.
>

Yes, it is controversial. All they have is very neat computer
simulations matching ageing to resources.

But as the article points out, there are problems with the two other
theories of why humans age.
The “mutation accumulation” theory, where the repair mechanism wears
out and the “antagonistic pleiotropy” theory, where traits that are
beneficial in early life are detrimental in later life.

The simulation shows "evolution favors shorter lifespans in
environments where resources are scarce and when pressures to
procreate are particularly intense". That might well not be the
complete answer. But traits that benefit species survival rather than
individuals seem likely.

Assuming a species had a very long lifespan, then what might the results be?
Reproduction beyond the capacity of the environment to support them is
obvious, (boom and bust) so that would be a limiting factor. Long-life
species would grow to match their environment and become slow
reproducers, so they would have less evolution. A change in the
environment would wipe them out.

In the continually changing early world environment, there would be no
evolutionary benefit to very long lifespan. Now that we are finding
genes that appear to affect ageing, we may soon be able to switch
these genes off and extend lifespan.


BillK