While visiting Yellowstone National Park, we stopped at the Grand Prismatic. While walking the paths that the park engineers have created to make sure that the Geyser Basin and its unique ecosystem "mats" (the thermophilic bacteria and algae that thrive in the hot, mineral-rich waters) are protected from visitors and allow people to get pretty close to the springs while still maintaining distance, does not keep out the bison.

I have no clue how this limb ended up on the mats since it is strictly prohibited to walk, touch or disturb them in any way, but it made for a very striking contrasting photo.