The Canada Goose discussion...

Regarding this discussion on "invasive species" as we call them here in the U.S., you might be interested in what Charles Darwin said in his Voyage of the Beagle in 1836 during his visit to Australia.  [http://www.infidels.org/library/historical/charles_darwin/voyage_of_beagle/Chapter19.html]

Even then he noted that the "number of aborigines is rapidly decreasing....  This decrease, no doubt, must be partly owing to the introduction of spirits, to European diseases...and to the gradual extinction of the wi ld animals...."  Of course

Darwin was writing before the germ theory was well understood, but he noted that:  "Besides the several evident causes of destruction, there appears to be some more mysterious agency generally at work.

Current theory of invasiveness regards introduced diseases and parasites as a major factor in the dominance of the invasive species over the native species.  The difference is that the native has evolved to local conditions over a long period of time (usually thousands of years).  The line between native and introduced must therefore lie somewhere in the thousands of years.  Under this test of "nativeness" both the Dingo and the aboriginal humans are nati v e, but the Canada Goose is not.  

Jim Tate
2031 Huidekoper Place NW
Washington, DC 20007
202 841-2056 
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