I love lichens because they are very beautiful patterns in Nature that I love to photograph. In addition to providing pretty pictures, lichens are living demonstrations of connections in Nature. A lichen is composed of at least two different but connected organisms - a fungus and a colony of microscopic green algae or a cyanobacteria. The fungus supplies a root structure, the lichen shape, and reproductive structures. The fungus is also able to find, soak up, and retain water and nutrients. Attached to the fungus are algae or bacterial cells which provide the ability to photosynthesize - something a fungus cannot do. In effect, the fungus is fed by the photosynthetic partner. The photosynthetic partners in lichens cannot live outside their host, nor can the host live without its partners. This kind of relationship between two or more organisms, where all organisms are changed by their union, is known as mutualism.