[fleddr]

I think it's just a roll of the dice with age as a side effect.

Evolution's primary mechanism is to promote traits that increase the likelihood that you'll survive until you can reproduce. Perhaps multiple times. And for some species an additional period to raise the new generation.

So if evolution selects for a hard protective shell, this increases the odds that you reach reproductive age, which is the goal. This may accidentally also add an additional 100 years of lifespan. Which does nothing for reproduction, but it just happens anyway.

[shadowofneptune]

Yeah, the lack of connection to reproduction is why I'm skeptical of aging being an evolutionary mechanism. The above quote (appears to be from Steve Jobs) seems like an application of old ideas about the natural order to our current understanding.

[fleddr]

I think Jobs' comments are indeed to be seen within the human cultural context only. Culture being a fancy word for stuff we made up.

Quite a few examples in nature where species drop dead directly after mating.

[go_elmo]

I disagree. If we would not age and stay 25 years old until we have an accident, we could have hundreds of children each, which would drastically increase reproduction and should therefore be preferred by evolutionary selection.