THE ANSWER TO YESTERDAY'S MYSTERY QUESTION
I enjoyed the creativity of some responses - the work of tiny crabs, huge dung beetles, the rocks brakes failed!
If you mentioned weather, you were headed in the right direction.
This is an amazing place in California. It’s called Death Valley National Park. The National Park is known for its very specific lake. It dried up long, and 60 pound rocks move by themselves along its bottom, leaving long furrows behind.
For a long time, the phenomenon of sliding rocks could not be understood. But in 2014, scientists finally found a scientific explanation. It turned out the reason why rocks slide is ice on frosty nights. The remnants of moisture under the rocks, freezes. In the morning the ice begins to melt and break up, and the rock moves.