I think that's a desired feature in future releases. I'm waiting to finish building my new PC, so I haven't tried 0.99 yet to see what improvements have been made in this area.
I'd like to see it go as far as to be able to choose the levels of survivability. Like, short term, long term. Whether or not Humans could prevail or just get by...without eventually becoming unrecognizable as Humans after a few decades or so. lol