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RE: hybrids

Bill Gould wrote;

<<What is a man made hybrid
different than any "natural species"? Do we believe that we are so far
departed from nature that we are not part of nature? No, I believe that it
part of evolution for man to take an active roll in the development and
preservation of certain genetic characteristics, and to enhance them.>>

There is such a thing as a natural hybrid, but in many ways man made hybrids
are very different, IMHO. Natural hybrids are most often either sterile, or
indicate a species that is in the process of rapid speciation. The former
provide an interesting biological oddity that occassionally is ornamental
enough to enter the nursery trade, but both are primarily of interest to
biologists and taxonomists who want to study the organisms in question.
Regardles, they also have evolved a very specific set of relationships with
the ecosystems around them. This ecological context is completely absent in
man made hybrids, and therefore the value of the plant as habitat to
wildlife is often null and void, especially if the plant in question is in a
greenhouse or aquarium. That to me is a huge difference. People may try to
simulate as best they can a piece of a particular ecosystem in a tank, but
even a public aquarium with a huge tank can only hint at the complexities of
the relationships the plants and animals would have in the wild. For
example, one of the biggest missing links in aquariums is the lack of insect
life. This is understandable since there are not many of us (myself
included) who want to deal with the hatched out adults flying around in our
homes, and difficult to control since the adults rarely return their
fertilized eggs to the environment of the tank they came from. That doesn't
mean the lack of these relationships isn't a problem in ways we don't even
understand. For one thing, insects are much better polinators than your
typical hobbiest (assuming you have the right polinator forthe plant in

I am not trying to denigrate your enjoyment of your favorite orchid, or of
any of the plants we use in our tanks. But the orchid on your windowsill
does little for the environment around it, hybrid or not. At least the
plants in the aquarium are serving at least part of their natural biological
function by helping filter the water to keep the fish happy. I suppose you
could claim that windowsill plants are similarly cleaning the air, but I
suspect you could take the plants out of the house without your getting
sick, but your fish would react very differently to the lack of plants in
their tank.

I also think it is important to point out that the majority of wetland
species tend to propagate primarily by asexual means, and seedling rates can
be very low for many species. In other words, natural propagation is as much
by spreading rhizomes, bulb offsets, root cuttings, stem cuttings, and the
like more often than seedling recruitment. This is a gross
over-generalization, and I am sure someone who knows the specific biology of
a few plants can cite exceptions, but in general this is true. Wetlands are
simply too violently changeable for seedling recruitment to be the only
option. While in Panama I remember watching the river below my house flood
three or four feet on an almost daily basis in the rainy season. Few
seedlings can survive that kind of constant scouring.

Oh, and I did not mean to say or imply that variegated plants are hybrids.
They are usually sports, selected for the trait of having spotted or
marbled, striped or otherwise marked leaves. This can be either genetic or
the result of viral damage to the plant (usually considered a bad thing, but
sometimes produces some rather remarkable effects, like the old 'Darwin'
tulips that would be splashed in two different colors.) There are many
plants that naturally produce patterned foliage (just look at the wonderful
tigering on some of the darker varieties of crypts,) but this is usually a
more regular trait (following the veins, or midribs a different color, etc.)
Sometimes you can accentuate a color through hybridizing, (ie, in some
plants that are naturally reddish, but difficult to grow, you can cross the
difficult one with an easy but less colorful one and develope a plant that
is easier to grow but has the better color.) This is more common with
flowers than foliage (roses are a good example) but there are a few examples
of foliage plants where this has been done.

Brett Johnson
Green Man Gardens
bnbjohns @ home . com