Carl Zimmer considers the question:
[Last] week in the New York Times, I write about new research on why invasive species thrive. Some scientists argue that native ecosystems have to be weakened for aliens to take hold. Some favor the idea that alien species gain an advantage by leaving their parasites and predators behind.
But a pair of ecologists, Jason Fridley and Dov Sax, argue that something else may be going on. It may simply be that the invasive species are superior. …
Fridley and Sax have drawn on some remarks by Darwin to develop what they call the Evolutionary Imbalance Hypothesis. They argue that species in different parts of the world have adapted to similar physical conditions. East Asia is a lot like Connecticut, for example, in terms of its climate. The species in both places have evolved, as natural selection improved their ability to survive, grow, and reproduce. It’s conceivable that a species in one place might get better at all that than a species somewhere else. It would be, in other words, superior. That doesn’t mean that this species would be some kind of Platonic ideal, or that it was a kind of Aryan paragon. It simply produced more offspring under identical conditions than another species.
The possible implications of this research:
One of the things that make ecosystems worth saving is the services they provide us with. If a superior species swoops in, it may do a better job at some of those services than native ones. An alien plant might draw more carbon dioxide out of the atmosphere and store it away in the soil, for example. Maybe we’ll be better off with an invaded ecosystem? I may not be fond of the barberry infiltrating the New England forests, but maybe our decisions about managing the wilderness have to be based on more than aesthetics.
(Photo by Katie Ashdown)
The Dish 