The rocks on this barren, windswept peak are covered in brilliantly colored swaths of orange lichen. Most lichens grow slowly and are among some of the oldest plants on earth. In really harsh conditions, they can simply shut down metabolism and survive for years in a dormant state, returning to life when conditions improve. Many reproduce simply when fragments are broken off and scattered to take a hold elsewhere. In order to survive in the hostile climates where little else lives, lichen produce over 500 chemical compounds that serve to control light exposure, repel herbivores, kill attacking microbes, and discourage competition from plants. In desert regions, lichen is often the substance that binds the soil, preventing it from blowing away. Lichen often serves as 'a canary in a coal mine', warning us of air degradation. It's extremely sensitive to air pollution and rarely thrives in areas with dirty air.