In the chapter 6 and 7 of Rambunctious Garden, Marris talks about the invasive species. The invasive species became a major problem in modern ecosystems. Marris discusses how the invasive species have bad reputation since they are exotic species that are foreign to specific ecosystem. Unlike the general opinion that disfavors the invasive species, Marris decides to argue the benefits of having exotic species. Mark Davis, an ecologist, argues that there are positive effects to introduce exotic species and letting them flourish in the new environment. Davis demonstrates how “sometimes newcomers might help natives flourish” by giving example of Pyura praeputialis in Australia. (pg 105). In this case, the exotic species helped the algae in the water to flourish, benefiting many other organisms in the water including the natural species. She continually argues that the introduction of exotic species does not necessarily mean the extinction of the natural species in the ecosystem. Furthermore, statistically, many of the introductions failed. I somehow agree with Marris’s point that the introduction or the assisted migration benefits the ecosystem including the survival of the exotic species and the natural species. However, it is obvious that Marris is exaggerating since she does not fully demonstrate the extreme case of damages that the exotic species had done. She only speaks about the benefits and tends to minimize the damages that the modern ecosystems are suffering from.
Later on, Marris continues her argument by introducing the concept of “novel ecosystems.” In those situations, the exotic species are left on their own in new ecosystem with no regulation by humans or other species. Marris begins to talk about the benefits of the novel ecosystems since the exotic species bring better food chain, faster growth, and more efficient nutrient cycling. At the same time, Marris admits that there are some down-sides of the novel ecosystems since it also can being “homogenization and extinction.” In this case, Marris demonstrates the situation of mango species on how it was introduced and flourished with many benefits. However, it must be noted that the successful introduction happens “sometimes” not “all the time” as the tone of Marris suggests. It is possible to say the novel ecosystem can be the best alternative for exotic species that are close to extinction is their native ecosystems. However, such situation must be examined carefully since many fear the disadvantages of the exotic species.
My point of view is against on the exotic species. The records show that the exotic species causes more trouble than benefiting the introduced ecosystems. May exotic species extinct or endangered native species and harmed the natural cycle of the ecosystem. Moreover, many humans suffered from the disadvantages that the exotic species had brought such as pathogens. What make the invasive species so hated my humans is that once they settle, it is hard to remove the species and repair the damages. In the chapter 6 and 7, I was disappointed at Marris as she denies to look at the reality on how bad the exotic species are to the modern ecosystems
