CSflim

I think there are two seperate arguments at work here.

There is the actual biological fact that recieving a mortal wound will flood your body with endorphins. I explained above why this occurs, and why it does not in any way contradict evolution. The more trauma, the more endorphins.

As for the sense of "feeling at peace" argument, well, like you said this is not an established fact, though I am sure that it happens in many cases (as well as the very opposite in plenty other cases). But again, I don't see how this is supposed to challenge evolution. It seems to me a rather simple psychological phenomenon.

EDIT: And the fact that not every human trait has any obvious survival benefit does not prove evolution wrong.
e.g. There doesn't seem to be a huge amount of survival benfit in appreciating beautiful sunsets! or music, or art, or whatever. Doesn't prove evolution wrong.
Since there is no complete model of how the human mind works, we cannot definitively say why humans tend to do X. Only armed with such knowledge can we begin to try and understand why such traits evolved.

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