Before there were complicated plants like those that produce flowers and have vascular systems, moss was the only kind of plant growing on land on the whole planet.
It must have looked really cool.
When it’s too hot, too dry, or too frigid out, moss dessicates into a dusty brown, dry fuzz that is barely noticeable. But within days of the arrival of cool, wet weather- like what we’ve mostly gotten in Philly the last couple of months- moss rehydrates into those gleaming, luscious, furry pelts that slowly spread over compacted, shady areas of the ground, dead trees, and rocks.
Moss grows great on rock (or asphalt shingles, or old tires) because it gets its nutrients and water from the air, not the ground. The spores will drop anchor on anything that has a favorable combination of shade, pH, and moisture.
I’ve been collecting moss to press into the joints of a stone wall, and I keep an empty Altoids tin in my purse in case I come across a piece that is particularly beautiful. I do fantasize about a mossy world, or at least my very small speck of it crammed with as much moss as possible.