I didn't witness it die, but when I was on my trip in Israel, my group was walking on our way to ride camels. On the way, we saw a dead dog that was under an overpass. It had no eyeballs, it's forearm bone was sticking out of its arm. It was crushed flat, presumably from a car that was travelling on the overpass. Also in the same area was a dead cat, but I didn't get a good look at it. The stench was terrible!
Scariest thing I've done/seen: I was riding on the local bike path going at around 22mph. There was a large industrial trashcan on the left side of the path, so I couldn't see anyone coming. As I got closer, I still saw nobody from around the trashcan, so I decided to pass the trashcan. As I passed it, a couple road cyclists travelling at 25+mph also passed it from the opposite direction. I could feel the male (there was a male and a female cyclist, presumably together) cyclist's arm hair on my arm. It was terrifying.
Worst thing I've done: I was riding the path on a downhill part. I came to a turn, where I normally just take a narrow turn and cross into the opposite direction's lane. There were people coming from the opposite direction, so I couldn't take a narrow turn like I wanted. I was going at 30+mph, so I had to think quick. I slowed down as much as I could, but I still took too wide of a turn and got into the dirt on the side of the path. Since I have 28mm slick tires with no tread whatsoever, I stayed upright for about 10ft and then lost control and fell. I probably slid on the ground after falling for another 5-10ft. I have clipless pedals (relatively new, so I am still getting used to them), which hold my feet to the pedals. I couldn't get my feet off of the pedals to stabilize myself, so I just fell on my left side of my body with both of my feet and both of my hands on the bike. I think that was the best thing I could've done, because if I stuck my arm out, I probably could have broken it. My left shoulder hurt for a week, but after that I was fine. Also, had I not been wearing long sleeves and my knickers (full-length spandex pants) as opposed to my short sleeve jersey and shorts, I probably would have had terrible road rash with sand and dirt embedded in my skin.