Lichen is a self-sustaining symbiosis between fungi and algae: a biological partnership that has persisted for over 400 million years. This collaboration enables lichen to survive where almost nothing else can – on bare rock, in deserts, the Arctic, and even the vacuum-like conditions of space.

Its biology: Resilience

Lichen is chemically sophisticated. It produces hundreds of secondary metabolites, many with documented antibacterial, antiviral and cytotoxic activity. It accumulates minerals directly from the atmosphere and functions as one of the world’s most reliable bioindicators, making visible what is otherwise invisible: the health of an ecosystem.

Nutritionally, lichen offers more than survival. Depending on the species, it contains complex carbohydrates, iron and vitamins including B12 and D. Those carbohydrates matter. The human brain depends primarily on glucose for energy; protein alone cannot sustain cognitive function. Lichen also contains bitter compounds — molecules systematically removed from modern diets despite their role in digestion and metabolic regulation.

Its abundance is equally overlooked.

Lichen represents approximately 7 % of Earth’s terrestrial biomass. Humans account for roughly 0.01 percent. One is considered primitive. The other considers itself advanced.