"Guano is a self-sustaining ecosystem"

This weekend, our professors brought us to the Eureka Volcano, nestled in the middle of the Andes and closer to Argentina than Valdivia. At the foot of the mountain are lava caves. They are the only tourable lava caves in South America and we were happy to get out of the poring rain and into the caves. Unfortunately, there wasn't any guano in the caves. The only animal that survives these beasts are small crickets. With or without guano, these caves were Planet Earth material.

There were different types of lava formations. Some looked like cow dung
and others looked like chocolate.
The caves were fully lit and professional then when we hit the end, they turned off the lights and we had a moment in the silence. You couldn't tell if your eyes were open or closed. It was my favorite part of the tour. So for all those curious what it looked like, I included a picture.