I did make it to Prehistorica, the Dawn Kingdoms and chose to travel back to the Mesozoic Era (the only choice). I expected some attacks by what animals were roaming then, but it seems I should have stopped in the shop and bought a dinosaur avatar first and become my own prehistoric beast. A few people did, but I was not frightened of them.
It was a well-made, lush sim but lacked enough to do. If there were any hiding dinosaurs, I wish they had come out to chase me. The one dragon you see was someone’s avatar and while interesting to look at, he did not know his role very well. There were a couple of gnat avatars flying around and being annoying—avatars, too.