Marris Ch6-7

Marris does not seem to think that invasive species are as harmful as people think them to be. She first explains how people currently view invasive species, which is: invasive species will only bring harm to the environment it is introduced. Because majority people believe that foreign species will take over the new environment and destroy the native species of that environment, the positive aspects of invasive species are shaded. For example, on Rodrigues Island, when the forest was being cut down the three species living on that island faced extinction. This was because they depended on the fruits and nectar from trees in the forest, as well as the insects living in the forest. The situation became extremely dire as the number of bird species was declining down to ten birds. So to save the species, the island was reforested with exotic species. “The trees were chosen without regard to conservation and included some notorious pests.” However, the introduction of the exotic species did damage the environment, but had saved it instead. Marris states that prejudice against the exotic species because they were still “invasive species” led to their exile from the Rodrigues Island. This proves that Marris does not really think of foreign species as invasive species if they prove helpful to nature in areas they are introduced to. Also, Marris brings up the Dov Sax’s paper American Naturalist, which spoke of increased “diversity of overall oceanic islands.” Sax’s research showed that invasive species were not illustrating the competition over resources, which would lead to native species extinctions, nor were they displaying a take over of the ecosystem. Marris concludes from Sax’s paper that extinctions did not occur because of “introduced species on continents.” Marris’ standpoint opened my eyes to the positive effects of “invasive” species, but the negative effects from purposely introducing foreign species overpower the positive aspects.

The success of novel ecosystems seems beneficial for nature and people even though some ecologists disapprove of them as they consist of majorly of invasive species. In Puerto Rico, the people treasure some invasive species-such as the flame tree and the mango tree-thriving there. However, some ecologists are so prejudiced against invasive species that they even prevented Puerto Rico from making an invasive specie its’ official plant. This prejudice should be changed. Because invasive species are located in different areas and not creating any harm, they are increasing the chances of that breed’s survival. For example, the flame tree is an invasive specie in Puerto Rico, but if it were not there it may have gone extinct as the flame tree is threatened in its native land-Madagascar. Lugo’s research of how the pine tree-an invasive specie on Puerto Rico’s pine plantations-was more productive than its neighboring natives. Ecologists should not grudge against novel ecosystems just because they do not illustrate the “stereotypes of invasive species…[forming] monocultures.” Novel ecosystems are still a part of nature and they are helping improve nature with their stability and productivity.

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