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Re: Plant Taxonomy
"On the plant taxonomy, I am waiting for the dust to settle. I have seen
go around and around several times. Ultimately we gain new understanding."
Jean, you said in another post that you were an "old geezer"...lol.... I
hope that you're planning on sticking around at least as long as the British
Queen Mother did, because this is certainly not going to be settled any time
My qualms with the original post, which seemed to claime that it was ONLY
flower/fruit/seed which are used to separate different plants from one
another is that there is no ONE combination of characteristics which works
for every group of plants - so one cannot make blanket statements as though
this was the case. If it was ONLY flower/fruit/seeds, how would you decide
how to separate plants which do not flower (i.e. mosses, liverworts,
ferns)??? The reproductive organs of angiosperms are doubtlessly important
but they are not the only things that can or must be considered.
There are _many_ different characteristics which can prove useful to a
taxonomist and it really isn't relevant to compare a plant with a
chimpanzee. Although, from what I have been learning, a chimpanzee is
probably closer to a rose than a rose is to some bacteria.
You also gave us some insight into your beliefs regarding "speciation", vis
a vis the inability of dogs and cats to interbreed. The concept of "species"
is still subject to great debate and again, no one definition fits all
living things nor even all plants. Some species seem to be very closely
defined while others exhibit a wide range of variation. As amateurs, we
cannot hope to do better but rely on "scientists" however much some may feel
that they often operate in a vacuum. There isn't much doubt that a Swordtail
belongs to a different species than a Platy, yet they have the ability, at
least in captivity, to easily interbreed and produce some very attractive
and viable offspring. And many varieties of cultivated Orchids have been
produced in which even wider genetic gulfs have been crossed. The world is
not black and white, it displays a multitude of varying hues, woven together
into an incredible fabric called life.
While I don't think that cats can mate with dogs, I have learned that there
may have been instances where seemingly vast genetic barriers have been
crossed. We live in a world with an Oxygen rich atmosphere, produced by
green plants via photosynthesis. It has been theorized that the chloroplasts
which inhabit the cells of green plants were at one time in the very distant
past independently living cells which became symbionts with the ancestors of
all plants, eventually giving up their solitary existance and becoming part
and parcel of the other cell. Since they no longer exist alone, at some
point in time there must have been some genetic cross-over from the
chloroplast ancestor to the other cell which got passed on and eventually
evolved into the plants we know today. Of course, that is merely a theory
and will probably remain contentious at least until some genius working in
his dark lab invents time travel and we can go back for ourselves and check.
Then again, some will continue to argue that the World was created in 6 days
and we all need a break on Sunday.....