I watched a squirrel running on an intercept vector across a yard and the road at me. Hit my front wheel yet still managed to get through/around my bike and up the ditch on the side of the road.
I swear some of these squirrels are suicidal.
Or just like the Geico commercial:
Squirrel Causes Car Accident Geico Commercial - YouTube
I did see a rider get hit by a deer years ago. Doe jumped, hit a rider in the head and totally ruined the paceline. After making sure the bike was okay, we called an ambulance which took both rider and bike to the hospital. He was a bit confused and his helmet was cracked but recovered just fine. Doe was okay, too. She came back to the scene of the crime as her two fawns were still on the other side of the road.