Species - Map Lichen (Rhizocarpon geographicum)
Location - Various
Grid Ref - Various
Map Lichen is named because on a close examination of this lime green species it looks like a map of an inner city, and the Latin name ‘Geographicum’ also points towards Geography. Map Lichen can be found on exposed rocks in most parts of the world, and some Map Lichens found in the arctic are believed to be about 8,600 years old which makes it the oldest living organism on earth.
What is fascinating about this Lichen is that it is a classic example of Symbiosis, i.e. two organisms living and working together in harmony, these two organisms being algae and fungi. The algae feeds the fungi through photosynthesis, and the fungi covers the algae and protects it.
As Map Lichen is found in most of the mountainous areas of the UK, it is one of the first species that any aspiring Mountain Leader will learn about, and is probably one of the most used topics on the ML’s 5 minute presentation during their assessment week.
There is a whole science dedicated to Lichens called Lichenometry, this science determines how long a rock has been exposed to the elements by looking at the size of the lichens on the rock, and elevation, pollution, temperature etc are all taken into account.
Map Lichen was actually taken into space on the space shuttle where it was exposed to the elements for 10 days, and it showed little or no change.
