You can learn a lot from a series of unfortunate events. Collapsed caves can leave entry holes on the surface that become hazards to local fauna. The image below is from inside a famous natural pitfall trap in Wyoming. The surface above is rather flat and prey running from a predator sometimes fall into this hole or prey smelling the decaying remains of dead accident victims may lean over too far for a closer look and fall in themselves. Over years, decades, and even tens of thousands of years, remains of animals and sediments in the trap accumulate preserving a chronology of historical events that we can read today.