Tough as Lichen

"Lichenes" from Ernst Haeckel's Artforms of Nature, 1904

I read somewhere recently that lichens are the slowest growing plants in the world.  My mom then told me that in the southern mountains of Peru, she's seen small tufts of lichen that the locals tell her are hundreds of years old.  They grow without soil, in deserts and the arctic as well as lush forests, and can act as biomonitors of atmospheric quality. 

And they're beautiful.

Top print available here.