by Perry McCarney

Created on: October 03, 2008   Last Updated: November 26, 2010

It is accepted by most that the world's biodiversity is shrinking; the majority of scientists involved in ecology agree that the world is currently undergoing a sixth major extinction period. That we are losing species at a rate of 100 to 1000 times above the natural background extinction rate. While this is true on a global basis, many may be surprised to learn that it does not necessarily mean that the biodiversity of an area or region is necessarily reducing, in fact many areas are experiencing increased biodiversity, at least temporarily in evolutionary terms.

While some endemic Australian species have become extinct since and due to European settlement, particularly in Tasmania, and many have become endangered, the biodiversity of Australia has actually increased. Unfortunately this is not something worthy of rejoicing, because the increase of biodiversity is due to the introduction of numerous domesticated species and the weeds and pests that humanity has managed to spread world-wide by accident and thoughtless disregard.

A multitude of species have learned to adapt their ecology to humans and have spread throughout the planet with us; rats and cockroaches are merely the most obvious. These species are referred to as "cosmopolitan" species; while their accidental introduction in many areas can technically mean an increase in local biodiversity, it's an increase that is likely to be relatively short-lived. They compete for resources with the natives or prey upon them, but do not have their own natural predators, parasites or pathogenic diseases controlling their numbers in the new environment.

Another significant factor impacting the natural biodiversity of Australia is the conversion of large tracts of arable land to European style farmland, pastures and fruit production, and the large scale water irrigation and control required to maintain these European agricultural bastions in the face of an environment that can only be considered hostile to them. The settlers even introduced species of no agricultural value because of a desire to turn their new home into a duplicate of their old European countries, rather than appreciate the beauty of the new, to them, natural world they had come to.

Humans always desire to control their environment rather than adapt to its vagaries. The forestlands of Australia have evolved many tree species that germinate and spread through the efficacy of forest fires. They actually require such natural "disasters" as part of

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