Lichens are the result of a symbiotic relationship between algae and fungi. The fungus portion of a plant provides the physical support, while the algae carries out the photosynthesis that provides food and energy. Lichens are able to use moisture from humid air as well as from fog.
When looking closely at lichens you will notice that the colour and form vary considerably. Some are crustose, lying flat upon rocks or on gypsum soil crust. Others are foliose with aerial parts standing up off the soil surface. they may range from orange to green, grey, black or brown.
Lichens often grow where gypsum is near the surface, being one reason why it is so easily destroyed. Along the Messum Crater Route you will find one of the richest lichen stretches in the Namib Desert, characterized by mostly green foliose lichen.
When viewing green lichen it is good to do it early in the morning when it is still moist from fog or pour a little water on it to experience their vivid colours when the leaves curl open during photosynthesis.
The Damara Tern, one of the rarest seabirds in southern Africa, make their nests in shallow scrapes on the ground amongst the lichens, which provide an excellent camouflage for eggs and chicks. Their nesting grounds are always between the coastal road and the sea; therefore their habitat is threatened by thoughtless and reckless off-road driving.