Yes elderly means they are "old" and will die soon the higher the level of medicine the longer they live but none the less that's your little warning they are getting on in years. I recemend getting your Harvesting and construction as soon as possible science spirtuality medicine and I waited untill last to get my 3rd Fertility. But the fastest way to gain points is through Science. You need level three of harvesting aka food just to servive plain and simple. Berries and crops run out, fishing is unlimited! You do need to breed though I think the dieing when you are over 9 villagers is just a bad run of luck but nothing you should worry about. Hope that helped a little!