Day 106:
I feel like the digging will never end.
Add one to the xenobiology list: we appear to have something resembling bats. Mammalian-like as far as I can tell (not getting that close), hang upside-down from the roofs of caves.
One big difference: these are not using ultrasonic frequencies. I can hear them just fine. And they squeak incessantly. Like flying rats at a rat political convention discussing rat business.
