Lichens are composed of two organisms living beneficially
together and forming a new life form.
The dominant partner in the relationship is a fungus. Fungi, of themselves, are incapable of making
their own food and survive by being parasites and decomposers. The lichen fungi cultivate partners that
manufacture food by photosynthesis, such as algae (Kingdom Protista)
and cyanobacteria (Kingdom Monera),
formerly called blue-green algae. The
relationship is symbiotic, with both organisms benefiting from the
fungi part breaks down rock, wood, and other organic matter to provide minerals
and nutrients to the relationship. The
algae part has chlorophyll and is able to supply the relationship with energy
through photosynthesis. Thus, by living
together, they can utilize a wide variety of habitats in which, alone, they
could not survive, such as deserts and the Arctic. In many cases, a lichen’s
fungi and algae can be found living in nature separately, but many lichens
consist of fungi that have become dependant on their algae partner and cannot
survive on their own.
in spots that are too harsh or limited for most other organisms—such as bare
rock, desert sand, cleared soil, dead wood, animal bones, and living
bark—lichens can survive extremes of heat, cold, and drought and are able to
shut down metabolically during these periods of unfavorable conditions. One species, the vagrant lichen, is even
mobile, moving from place to place by the wind.
Lichens can colonize almost any undisturbed surface if given appropriate
amounts of light and moisture, clean air, and lack of competition. It is estimated that lichens are the dominant
vegetation on eight percent of the earth’s terrestrial surface.
are highly diverse in looks, varying from gray and green rosettes on trees,
green to orange crusts on rocks, tangled brown to green hair hanging from
branches, to tiny green goblets on the ground.
They are very slow growers, often growing less than a millimeter per
year, and are believed to be among the oldest living things on earth.
produce an arsenal of more than 500 unique biochemical compounds that serve to
control light exposure, repel herbivores, kill attacking microbes, and
discourage competition from plants.
Among these are many pigments and antibiotics that are very useful to
man. Half of all lichen species have
antibiotic properties. Worldwide,
lichens have been used for making dyes, medicines, poisons, clothes, soups,
jellies, breads, and fine perfumes.
Lichens with cyanobacteria contribute to soil
fertility in a major way by taking nitrogen gas from the air and turning it
into biologically usable compounds.
Lichens are also valuable as food and nesting material for a multitude
of wildlife, from the tiny hummingbird that camouflages its nest with it to the
large caribous of the far north, which depend on it for food during the long
as lichens are composed of two organisms living together and forming a new life
form, so the person who cultivates a relationship with Christ and unites his or
her life with Him becomes a new creature.
“Therefore if any man [be] in Christ, [he is] a new creature: old things
are passed away; behold, all things are become
new.” 11 Corinthians 5:17. “Our life is to be bound up with the life of
Christ; we are to draw constantly from Him, partaking of Him, the living Bread
that came down from heaven, drawing from a fountain ever fresh, ever giving
forth its abundant treasures.” Christ’s
Object Lessons, 129. “The
Christian’s life is not a modification or improvement of the old, but a
transformation of nature. There is a
death to self and sin, and a new life altogether.” The Desire of Ages, 172.