Dogs have no clue. Some how though I think it was more tragic for the dog since it lost it's life. The dogs were probably scared out onto the track by people chasing them in the first place. It was a poor effort though that the yellow flags weren't up sooner. This seems to happen a lot though in motor sport. In Australia it's kangaroos, lots of green grass around the tracks attracts them. I can't remember where it was but i remember a MotoGP rider hitting a dear too.
Good Kangaroo videos.
http://www.youtube.com/watch?v=YTeRHlZ8vDY
http://www.youtube.com/watch?v=ynQ8sBlyEIw
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