True, that's a good point. As far as evolution is concerned, if you have effectively raised offspring until you aren't fertile anymore then the warranty is up and all the time you get after that is a bonus. There isn't really much pressure to select for longevity after that period.

I've heard a lot of office buildings will leave every floor's fluorescent lights on in the winter to take a load off the overnight heating bills. I'm sure that lessens the lifespan of the bulbs and ballasts, but for people to adopt that practice it must still be economical in the final tally.

Who knows, I'd love to see more study on this because I think everybody in history has always wondered what the hell is up with dreams. "To keep your noggin warm" seems like a super anticlimactic purpose and I love it. It's so absurd and nihilistic it's funny, which kind of jives with nature's whole style.