But with the rise of tools and technology, man ceased to be just
another primate in the ecosystem. He became man the technological
dominant, with the potential to alter fundamental ecosystem processes
through technological rather than ethological or evolutionary changes.
Suddenly, the ecological time frames of earth moved to a new and more
rapid beat.
It is postulated that among the earliest victims of man's technology
may have been some of the extinct large ungulates known to have lived in
North America. Animals such as the Giant Bison are presumed to have been
brought to extinction by man the technologically-armed hunter.
The first largescale alterations to ecosystems however would
come when man's developing technology enabled him to shift from
subsistence hunting and food gathering to domestication of livestock and
the establishment of plant cultivation. These actions seem to have given
rise to the city as we know it, a center of developing technology and
the economy now aimed at supplying man's wants usually in excess of his
needs.
Although it is often presumed that agriculture preceded the
development of the city, it is just as reasonable to assume that the
city as an ecosystem arose as a technological development of man and
made possible the rise of agriculture and the widespread creation of
human ecosystems.
The natural ecosystems that man systematically altered to produce his
agricultural and urban ecosystem gradually underwent some irreversible
changes. The object of plant and animal husbandry is to proliferate a
few wanted species In contrast to others deemed either as competitive
(and therefore to be eliminated), or worthless (and therefore to be
replaced.) Man's increasing technology enabled him to occupy more and
more land with agriculture and urban development, and the chopping up of
the great natural ecosystems began.
As those areas most suitable for agriculture came under the planting
stick or the plow, the landscape and its natural ecosystems began to
shift and change. Man's livestock came to occupy the grazing lands,
pushing out of existence the animals that normally occupied those
ecosystems. It in not true that man's activities merely drove the
extant animals into more remote habitats. All of the gazing lands of
earth were completely occupied before man began his great technological
development. The animals that were driven off the land could not
"retreat"there were no vacant lands for them to fall back on. They
simply died. Those that survived were on lands not desired by man or
those that could coexist with man. Animals that preyed upon man or his
livestock were simply killed as the opportunity permitted. The predators
that coexist with man today do so not out of man's compassion for
ecosystem diversity, but simply because man has been unable to eliminate
them. The coyote comes immediately to mind.
As the original vegetation patterns and ecosystems were altered by
man, new ecosystems formed. Primitive agricultural ecosystems at first
were confined to grazing lands, which often were extensive in area, and
to tilled lands. Early man simply did not have the tools or the
technology for large scale development of the landscape, and when he did
acquire them, they were used first to regulate water. Thus man's
earliest urban technological triumph gave rise to the irrigation
civilization of Sumer, Akkad, Assyria, and Babylon in the Fertile
Crescent, to the Egyptian development of the Nile Valley, and to the
Chinese development of the Yellow River Valley. In these, the earliest
of civilizations, the city and agriculture evolved simultaneously,
cities rising like volcanic islands out of a sea of agriculture.
The consequent pattern of development provided urban admixtures of
the original vegetation, the agriculture vegetation and domestic and
wild animals. The city as an ecosystem became a collection of niches
that provided habitats for man as well as for other animals and plants.
The variety of urban niches in some ways actually provides more
diversity than can be found in many ecosystems unmodified by man.
Cities were not planned to include wildlife, nor were they meant
necessarily to exclude plants other than shade trees, turf, and
ornamentals. In most cases, man does not decide what plants and animals
will inhabit a particular city; this decision is imposed upon him by
environmental circumstancesclimate and the prevailing
environmental conditions that make it possible for certain plants and
animal life to inhabit an area.
We are accustomed to think of modern city vegetation only in terms of
street plants, i.e.. shade trees, grass, turf, flowers, and similar
cultivations. But in those rare areas of cities that man has not invaded
and used for his technology, we are more likely to find the plants and
animals that are typical of the surrounding countryside.
In the first cities no doubt there was a continuity of habitat from
the surrounding countryside into the city, and probably a great deal of
wildlife was present in these cities; we know that many agricultural
animalschickens, sheep, goats, horses, cattlewere kept in
cities and considerable agriculture was carried on. Zoning laws against
chickens, horses, cows, etc., came late in city life.
It is equally certain that predators and other animals from the
surrounding area were frequent visitors to early cities. The cities
protected people from the predators that were the natural denizens of
the locality and the commons of these cities provided grazing for sheep
and other domestic animals under conditions that protected them from
marauding wildlife.
Even today there are recorded instances of wildlife wandering into
cities that stand adjacent to their habitat. In cities located in the
deciduous forest of the eastern United StatesPennsylvania for
instanceit is not uncommon for deer to wander through the towns.
In the early 1921 a black bear was shot in the kitchen of the Hotel
Duluth in Duluth, Minnesota. This intrepid beast was stuffed and is now
exhibited in that hotel's cocktail dispensarythe Black Beer
Lounge.
As cities developed in size and complexity, gradually progressing
from villages and crossroad market towns to huge metropolitan areas,
their impact upon the habitats of natural ecosystems grew enormously. In
addition to altering the existing ecosystems, the development of cities
created hundreds of thousands of new habitats and new ecosystems.
The city, then, began as a new form of earthly habitat, carved out of
natural and agricultural ecosystems that hitherto had harbored only
wildlife. In other instances, human use of the land has extirpated the
wildlife, or the construction of buildings has destroyed the animals'
habitat. Most cities still are contiguous to a rural hinterland of
natural ecosystems which provide a continuity of habitat and some cities
are even surrounded by native ecosystems. In this way, wildlife still is
provided with avenues into and out of similar habitats in the cities,
allowing them to be populated by animals from the surrounding
countryside.
When we think of the wildlife of the city, we tend to think only in
terms of conservation. We think of birds, squirrels and rabbits; in
short, those animals that are largely innocuous so far as man is
concerned. More realistically we must recognize that city wildlife
includes rats, vermin, insects, and all manner of other animal life
that does not fit our picture of ideal living conditions for man.
The environment of the city has been modified to provide a habitat
for man and to provide the locale and the means to operate man's
technology. The animals present fall into three categories: Those that
man wantsdogs, cats, horses, chickens. etc.: those that always accompany
man wherever he goes and which all on his waste productsrats,
mice, lice, bedbugs, cockroaches, and so forth: and those that are
welladjusted to the habitat created by man's activities such as
pigeons, English sparrows, starlings and bass.
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