This seems to imply that a species is native only if it evolves in the location where it is found, and that any species which arrives by migration or other form of transport is not native. This is a very Eulerian approach. In particular, with global warming we can expect species to drift towards the poles, so even though the entire ecosystem drifts polewards, can we say that the component species cease to be native?
Bill Silvert Habitat Ecologist ----- Original Message ----- From: <[EMAIL PROTECTED]> To: <[email protected]> Sent: Tuesday, May 02, 2006 3:08 PM Subject: Re: Introduced Sp. Question >I don't believe there is a "scientific" answer to this question. "Native" >means to me that a species has evolved in a particular ecosystem or >ecosystems in response to environmental factors in that/those ecosystems. >If we accept that definition, it is my opinion that no species introduced >by man, purposely or accidently, can become a "native". It might become >"naturalized" (able to survive and reproduce in the new environment as are >invasive exotics) but not "native". > > Bob Mowbray > Tropical Forest Ecologist > Natural Resource Management Specialist
