Lichens are an amazing example of the fact that cooperation is just as important as competition in the evolutionary process.

 

Lichens are an amazing example of the fact that competition is not the only force driving the evolutionary process. Cooperation is just as important. Each lichen is composed of both algae and fungi organisms living together in a symbiotic relationship. The algae contain chlorophyll which uses sunlight and carbon dioxide to produce carbohydrates for the nourishment of both organisms. The fungi, on the other hand, provide a substrate on which the algae can grow, as well as a primitive network of roots, called hyphae. These roots in turn secrete an acid that gradually dissolves the rock, allowing rudimentary soil to form. The soil is then available for use by small plants, which in turn decompose into larger soil particles when they die. While living, these plants serve as food for small animals, which in turn are eaten by larger animals. Where would any of us be without lichens?

Photo: Lichen growing on a sandstone boulder; Reservoir Ridge Natural Area; Larimer County, CO; January 8, 2014

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