Steven:
> I repeat, within the past 90 million years the place where I sit has been
> both the bottom of a salt water ocean and is now at over 5000 ft above sea
> level on the edge of grasslands and mountains. Is that an environmental
> change, not ecosystemic?
> Steven
I think Utah is the bottom of a salt water ocean situated at an elevation of
nearly 4000 feet (Great Salt Lake). Ecosystems are concepts....what you are
describing is a change, albeit not a change in an "ecosystem" as it is
conceived, but rather a change in the environment brought on by geologic
change (mountain building), and global climate.
Now if you were to ask the same question and living in Australia, the answer
would be that the nothing has changed...
Horses evolved and orginated in North America, but became extinct prior to
the last ice age. The Spanish brought them back....What environmental change
'occasioned' the extinction of the horse from Nth America, and thus how
could the horse be 're-introduced' and survive as wild horses on a continent
where it went extinct? Did the recent continental glaciation force it into
extinction.
Some ecosystems move or are simply recycled.....and some rejected....
chao
john foster
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