Here in the same forum, there is a thread that may help you/them!
It's in Forums List » Windows/Mac Games (and Palm/Pocket PC) » Virtual Villagers 3: The Secret City » My villagers are dying!! What am I doing wrong?

And I recommend you, in Forums List» The Guides » Virtual Villagers 3: The Secret City Guide » [SPOILERS] Guide to getting food in VV3