In the tribe I currently have in VV4, I've had the following events happen (my memory is a bit hazy on most, though, as I hadn't played this tribe for a very long time until yesterday):
-the mysterious fog appeared, resulting in the loss of all the tech points I had at the time (I'm pretty sure I've had that one happen more than once);
-the mysterious fog "stole" all the food I had at the time (twice in a row, and at the beginning, when they had very little food - needless to say it was more than a little annoying);
-Biggles appeared and allowed the villager to ask him a question (I think I got a Dendrology level out of that one);
-the one with the children fighting over a shell (I chose "teach how to share");
-the one where a child ate some food and had to lie or confess what he had done to the adults(he told the truth); -the aspiring doctor one (the villager got better - I think I might have had this one happen more than once too).