Dec 16, 2018
Sinkholes like this one in Xuanen, China, form from the natural movement of underground rivers and currents.
Eventually, a section of the roof will weaken and collapse, forming a portal to the underground passages below. Often, with the addition of sunlight from a collapsed roof, the fertile and moist underground passages become a hotbed for various plants and animals that form a biodiversity that is both largely unlike the species found on the surface, and is also very dependent on the specific composition of these underground spaces. ⠀
