Mel says: "We are discussing the plausibility
of an 'explosion' of epic proportions that is indicative of a decline
in the
livability of our world."

Read my posts again--I am not arguing that deer populations have
exploded. I have said that the major reason for any increase, if there
is one, is likely the activity of our species, to wit, "urbanization",
and that this activity does reduce the livability of our planet. I do
not limit the term "urban" to what occures in cities. Rather, it is the
wide range of human activities which, obviously and subtly, change
natural environments for our benefit, and which, in this age, are on
the "urban" end of the continuum (with the possible exception of those
quiet, tail-less neanders known to lurk here-abouts.)

I include in this category all industrial processes, and specifically
those of industrial agriculture, practiced on 349 million acres (that's
about 18% of the lower 48, BTW, if I use the figures you provided). I
include agriculture because we seem to have a terribly difficult time
thinking of farming as a industrial process when, in all likelihood,
your hypothetical farmer living in his hypothetical 1800 s.f. probably
tills, chemically treats, and otherwise manipulates better than 2000
acres of cropland (and in some parts of the country, many thousands
more), or oversees the production and feeding of thousands of head of
cattle/hogs/chickens--a scale of activity far beyond what is
traditionally thought of as "rural". Add to this 18% the additional
acreage affected by our use of that developed (built-upon?) 6%
(effluent, erosion, pollution, habitat disruption, etc.), and it's fair
to say we have a direct impact on better than 25% of the land mass (and
we haven't even begun to talk about air or water). The world is not so
simple that the consequences of our actions are confined to the merely
6% of "built" environment.

The fact that our activities are beneficial to a few species besides
our own does not mean we should ignore the consequences to the rest.
While our "development" may contribute to the increased viability (for
how long is yet unknown) of some species--deer--it is known to be
profoundly detrimental to very many more. This attitude of complacency
is what I call myopia. No credible source denies the decline and
extinction of species now occuring on the earth is due in large part to
human activity; this is no reason for celebration.

Dan