Well Josh, here are some things to think about. Humans are part of natural systems but that doesn't mean that everything that humans do is an acceptable part of nature. Take for example the atomic bomb or biological weapons. Should we accept these actions because humans are part of nature? Obviously not. Yet much research has shown that invasives may produce broad detrimental effects that are equivalent to the effects of bombs or poisons. In fact they can be more detrimental because the effects of toxins will wear off eventually, but invasive species are here to stay. Take San Francisco Bay-Delta ecosystem which is now dominated by invasive animals (anthropogenically transported) which have turned a formerly pelagic food web and fish fauna into a benthic food web for which few native species have adaptations to utilize. The flora and fauna of SF Bay look little like they did 150 years ago and that is a loss to everyone because this ecosystem was unique on the west coast of North America. Given that the invasive species already exist in their native ecosystems and are not imperiled why is it "natural" to allow them to have detrimental effects on native species found nowhere else?. How, and more importantly why, should this be considered part of a "natural" process? Frankly the argument that "humans are part of nature" and it's necessary logical extension "if humans do it it is natural" is not compelling to me because we limit all sorts of human behaviors (rape, murder, theft, etc.). So I would argue that anthropogenically introduced invasives are not natural because they result in negative impacts and even extinctions of species and that this aspect of human behavior should be regulated (as it is by the many laws that forbid transport of potentially invasive species).
On Sun, Apr 22, 2012 at 10:01 AM, Joshua Wilson <[email protected]>wrote: > Good morning, > > I know that invasive and non-native species have been getting a great deal > of attention lately, and justly. I understand the basic ecological impacts > and concerns invasive species cause, and the disruption of the native > system. My main question is: > > Why are invasive species considered a nuisance, instead of adaptation, > progression, or perhaps ecosystem evolution? > > Yes, human beings have been a main cause of the large majority of these > invasions. But even so, I feel we are part of the natural system. If an > invasive species exhibits more plasticity or is more competitive and > adaptive than the present species in an ecosystem, does that necessarily > imply catastrophic impacts? There are multiple arguments against this, I > know, many of them strong and verified. I am not an advocate of invasive > species dominated ecosystems, but am just curious why this change and shift > is considered so extremely detrimental. I feel that stable and progressive > change and adaptation is the basis of a strong ecological system. > > I would welcome any thoughts on this, or perhaps to start a discussion. I > am still an undergrad, so my question may seem farfetched and ridiculous to > some. Even so, just something to ponder on a lovely Sunday morning. > > Have a good day all, > > Josh Wilson > -- Gary D. Grossman, PhD Professor of Animal Ecology Warnell School of Forestry & Natural Resources University of Georgia Athens, GA, USA 30602 http://grossman.myweb.uga.edu/ <http://www.arches.uga.edu/%7Egrossman> Board of Editors - Animal Biodiversity and Conservation Editorial Board - Freshwater Biology Editorial Board - Ecology Freshwater Fish
