A story near and dear to my heart. I was raised about an hour from Yellowstone National Park and every hear, several people would get attacked/gored by the Bison. Usually it was because they would walk right up to these awesome animals and try to touch them or get a picture as close as they could. I can remember seeing dozens of tourists get out of their vehicles and walk right towards about 15-20 Bison who were grazing in a field.
http://www.fox5ny.com/news/264781196-story
While this story doesn't appear to be an egregious act by this elderly couple, it just reminded me of what can happen when nature meets civilization. Bison are a sight to behold. I have literally been in my vehicle and I could have reached out the window and touched one.