It’s easy to ignore lichen, those vaguely mossy patches on twigs, branches, stones, walls,… Yet lit up by a low November sun they prove to be rather attractive.

Now don’t they look like some sort of vegetation? Certainly the following looks rather akin to a moss.

But they are not. Moss is a plant; lichen is not. Lichen is actually type of fungus, but one that can only exist in symbiotic relationship with algae or cyanobacteria. The algae/cynobacteria provide the lichen with photosynthetic energy, while the lichen provides a protective environment.

According to Wiki, there are over 20,000 species of lichen, covering 6-8% of the surface of the earth. How easily we ignore such an incredibly successful life form.