Map Lichen

Map lichen creates distinctive yellow-green patches with black borders on rocks, resembling maps or country boundaries. It grows so slowly and predictably (0.1-0.5mm per year) that scientists use it to date rock surfaces - a technique called lichenometry. Colonies on some Norwegian rocks have been dated to over 8,600 years old.

Map lichen demonstrates competitive boundary formation. The black borders between colonies are battlefronts where different genetic individuals meet and neither can advance. This creates stable, negotiated boundaries that persist for centuries. The business parallel is mature market territories where competitors have established equilibrium positions - the boundaries rarely move because the cost of advance exceeds the benefit.