Not sure, but a couple of incidences come to mind. One, when I was a kid, we were at some stranger's house and I was in their backyard swinging on their swing, when their (big) dog walked right in front of the path of the swing and I couldn't stop.. I ran right into him, and then he opened his mouth against my face so that his top teeth were on my forehead and his bottom teeth were on my chin, or something like that.. fortunately, my velocity I still had from the swing pushed him off of me before he bit..

In another incident, I was at the everglades with my friend on the Anhinga trail, and I dropped the expensive (top-end) rechargeable batteries to my camera outside the trail.. the trail was elevated so the batteries were too far down for me to reach them, so I climbed over the rail to get to them.. while I was outside the trail, an alligator made a really fast motion toward me, and I got back over that rail pretty quickly. =p (You don't have to tell me I was an idiot..:p)