RE: Are civilized or uncivilized people more likely to survive?
I am not sure is civilized and uncivilized is the correct labels in this case. I believe I am a fairly civilized person, but compare me to the average person who spends their life trying to "get rich" and I know I have a much better chance of survival than they.
Perhaps, "close to nature" and "not close to nature" would be better labels. I have a degree in computer science and most of my life have been reasonable well off financially, but I have made a conscious choice to learn to understand nature and live within her bounds rather than expecting her to bend to my whims. I can walk out into my yard and find food other people would try to kill off. I have listened to the sounds of nature and can pick out the sounds of most predators and edible animals. I can look at land and see which areas are most apt to flood and can purify water from most any source. Perhaps best of all, I know when to be quiet because one of the best survival tips anyone can learn is you should understand what type of people are around you, long before they know you are there.
I think being more specific by saying close to nature or not close to nature does more suit the idea. Saying uncivilized/civilized is more general, and while they do cover the patterns a lot of people portray, it's not completely accurate since people are on more of a gradient scale. Living in civilization does tend to make people weaker, but not inherently so. Knowing how to live off of the land is crucial for survival, were any sort of catastrophic event to happen. Plus, as you have mentioned, living in civilization doesn't inherently make someone that civilized either, if they're power-hungry and care little about their impact on other life.