Lichen, a Symbol of Coexistence and Cooperation in Nature

Lichen as ‘an ecologically obligated, stable mutualism between an exhabitant fungal partner (mycobiont) and an inhabitant population of extracellularly located unicellular or filamentous algal or cyanobacterial cells (phycobiont). Lichens are not the only possible fungal/algal or fungal/cyanobacterial symbioses Some have the aspect of leaves; others cover the substrate like a crust, others such as the genus Ramalina adopt shrubby forms, and there are gelatinous lichens such as the genus Collema Lichens are named based on the fungal component, which plays the primary role in determining the lichen's form. The fungus typically comprises the majority of lichen’s bulk, though in filamentous and gelatinous lichens this is not always the case. The lichen fungus is typically a member of the Ascomycota and rarely a member of the Basidiomycota. Lichens are eaten by some different cultures across the world. Although some lichens are only eaten in times of famine, others are a staple food or even a delicacy. Additional lichens produce secondary compounds that are used in Cosmetics, Dyeing and Industries.