In chapter 6 and 7 of the book Rambunctious Garden, Emma Marris advocates that not all of the exotic species are harmful, in which some of them actually can be good to species’ development. Marris also introduces the concept of novel ecosystem, which is a “new, human-influenced combinations of species that can function as well or better than native ecosystems and provide for human with ecosystem services of various kinds (Marris, 160).” I think that scientists should start protecting those novel ecosystems because they are valuable, and actually increasing species diversity.
Many scientists think that exotic/foreign species are invasive species. Once these species are introduced into the new environment, they adapt to the new environment, and eventually become a threat to the native species. The main reason why scientists think that exotic species are their enemy is that “Sometimes a species naturalizes so well that it becomes a rowdy nuisance, taking over land or water previously held by natives, or eating them up or outcompeting them or fouling boat hulls or doing something else disagreeable (Marris, 142).” However, Sax published a paper that holds a completely different view about exotic species. Sax found out that the overall diversity of the island was actually increasing, in which the number of invasion is much greater than the number of extinction. He also argues that most extinction is not directly caused by those exotic species. In fact, according to the book, “extinctions that are directly attributable to introduced species are quite rare (Marris, 150).” Not only that, studies also shows that some of the exotic species are helping the native species to grow; for example, exotic birds replaced the roles of the extinct species in dispersing the seeds of the native plants in Hawaii. Some scientists started to think about exotic species in a more positive way. They introduced the concept of novel ecosystems, which are “defined by anthropogenic change by are not under active human management (Marris, 164).” Some novel ecosystems were purposely changed by people then leave it to go wild; others were changed indirectly by human, such as climate change, extinction, and invasion of the foreign species. According to Lugo’s research, the plantation with exotic species actually grows better than the native plantation. There are many scientists dislike the concept of novel systems because they think it doesn’t fit into their idea of pristine nature. According to Charles Elton, “a careful selection of exotic forms” could have a place beside natives in man-made landscapes designed to be “rich and interesting and stable” (Marris, 167).
As Marris says, “Novel ecosystem have proven to be useful for-of all thing- restoration of native species (Marris, 174)” I think that scientist should look deep into novel ecosystems, and maybe they will found a different approach to conservation. I agree with Marris that it doesn’t matter if the species were exotic or not, as long as they can benefit the ecosystem, they shouldn’t be treated as invasive species.
