What lichens have to tell us

They may be overlooked easily by the untrained eye, one of the oldest life forms on earth, lichens. Lichens were the first forms of life billions of years ago that managed to live on land. At that time there was no soil, no organic matter, just rock and that's where lichens flourish. Although small and unattractive to many, this life form is astonishingly good at survival at places where no other life form can live.

Lichens are a symbiotic life form between (several forms of) algae, bacteria and fungi. The fungi protects the algae from dehydrating and is able to fix itself onto rock, but also trees and even the surface of our modern cars. From the rock, tree, car, it is able to retrieve minerals for the algae and itself. The algae shares the quality of the plant kingdom to covert light energy into chemical energy. In simple words, it is the power to convert CO2 into C (carbon for growth) and O2 (oxygen). It also can produce sugars that are the power source for both to grow.

Lichens are remarkably resilient. Here in the uttermost southwestern tip of Europe I see the same kinds of lichens as I saw in the middle of Sweden. Thus it is able to withstand the hot and dry summers in Portugal and the cold winters in Sweden. That's a distance of 3.715 km! From an almost subtropical climate to an almost arctic climate. Keep that in mind when you see these little life forms with whom we share this world.

I use lichens to get an indication of how pure the air is in a region. Although lichens were able to survive previous mass extinctions, great worldwide weather changes and by far have outlived many species on this earth (including us), they are vulnerable to air pollution. Thus, if you want to know what quality of air you are breathing, look if you can find a lot of lichens. If not, you probably live in or next to an industrial and/or urban area.

Here in Alentejo, Portugal, there are abundant amounts of lichens which tell us the air here is clean and pure. Although small, together they are able to give the deciduous trees that live here a greyish color which adds to the beautiful color pallets that Portugal has to offer.

We have the right to live in places where the air is pure. We have the right to be healthy. And with us, all creatures of this beautiful planet have these rights too.

Wende