"Lichens are a successful alliance between a fungus and an alga. Each doing what it does best, and thriving as a result of a natural cooperation. They live as one organism, both inhabiting the same body. "
"Many lichens are very sensitive to pollution in the air. When there are too many harmful things in the air, lichens die. If you live where there are many lichens it probably means the air is clean. But, if there are only a few lichens in your neighborhood, the air you are breathing is probably clogged with automobile fumes or industrial wastes."
Lichens are capable of inhabiting several ecosystems, due to their versatility, despite of the environmental conditions. They can live on rocks, ground, rind of trees, trunks and wood. Lichens are very good bio-indicators to survey the air pollution.
I think this organism above is Fungi, not Lichen. Fungi help to recycle fallen timber and organic debris. Is it Rainbow Fungi or Coral Fungi? Perhaps someone can help me with this doubt!
"Humans have learned to use lichens in many useful ways. People eat lichens (careful a few are poisonous, so don't experiment without expert help). Drug companies make antibiotics from lichen substances. One of the most creative things people do with lichens is make dyes to color wool. "
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Update 1: Dyeing with Lichens & Mushrooms: Human beings have been used lichens for over 4,000 years in dyeing. The Romans produced a purple dye from lichens for their togas. In Scotland the traditional kilts were dyed from lichen extracts while native American Indians use lichen dyes for colour in their rugs. You can see this issue here , here and here .
Update 2: My friend Gisela, from Guildwood Village on The Lake kindly solve my doubt about Lichen and Fungi. As you can see here, "my" Fungi is Coral Fungi. If you want to see another beautiful photos of Fungi, Lichen and Mushroom, click on those Gisela's post: here, here, here, here, here and here. Thank you so much Gisela!