Springtails are very small six-legged animals, related to insects but from a more primitive evolutionary line. Here's an entry about one particular kind.

Rock balancing is really just a matter of placing one rock on top of another and feeling the right balance. The amazing thing for me was how easy it became once I learned that it was possible. I'm still a bit of a beginner. This is my teacher. This is her teacher.

Checking the rock for signs of disturbance was something that comes from my background of being a naturalist and my current job as a pest control tech.