Draft - University of Maine

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How are gymnosperms important?
30 September 2007
Chris Campbell, University of Maine
The world and human civilization would be very different if there were no pines,
redwoods, spruces, and other gymnosperms. These trees form extensive forests in many
cooler and colder regions of the world. These forests provide lumber for millions of
homes, wood for many other uses, most of our paper, and habitat for many species of
wildlife. These forests improve the air we breathe, generating oxygen and sequestering
carbon dioxide.
Gymnosperms are probably the leading source of timber in the world, and their wood is
used in many ways. The so-called soft pines, such as eastern and western white pine, are
excellent for paneling and furniture. In Colonial times, the King of England claimed all
large eastern white pines for potential use as masts for ships of the English navy. Other
pines, cedars, and Douglas fir are excellent for the structural parts of wooden homes, and
gymnosperm wood is used for telephone poles, decking, boats, shingles, pencils, natural
moth-proofing for closets, soundboards of stringed instruments (such as violins), and
numerous other purposes.
Cedars, pines, spruces, hemlocks, junipers, yews, and many other gymnosperms are
valuable ornamentals. It is surprising that some prized gymnosperm ornamentals have
much smaller geographic ranges than they had at some time in past and appear to be on
the brink of extinction in the wild. The maidenhair tree (ginkgo), for example, is
extremely rare in nature and has persisted in the world for thousands of years mostly as
ornamentals near religious buildings in eastern Asia. The dawn redwood was thought to
be a fossil until it was seen in a remote valley in China in the 1940’s. Despite their
tenuous status in nature, Ginkgo and the dawn redwood both grow very well as
ornamentals along the streets of large cities.
Gymnosperms are also fascinating organisms. They include the tallest (redwoods), most
massive (giant sequoias), and longest living trees (bristlecone pines). They are an old
group that dominated the earth during the time of dinosaurs, long before the origin of
flowering plants such as lilies, roses, and oaks. Gymnosperm genomes are huge, in some
cases at least ten times the size of the human genome, and organized in unique ways.
Despite their prominence in the world, we still have a lot to learn about these fascinating
plants. For instance, we are uncertain about many of the evolutionary or phylogenetic
relationships among the approximately 1100 species of living gymnosperms. We are also
unclear about fundamental relationships among these living gymnosperms and extinct
groups of gymnosperms plus the other major group of seed plants, the flowering plants. A
clearer view of the phylogeny of seed plants is critical to our knowledge and appreciation
of these important organisms.
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