@danon5,
April 2, 2011
Mother Nature’s Melting Pot
By HUGH RAFFLES
THE anti-immigrant sentiment sweeping the country, from draconian laws in Arizona to armed militias along the Mexican border, has taken many Americans by surprise. It shouldn’t — nativism runs deep in the United States. Just ask our non-native animals and plants: they too are commonly labeled as aliens, even though they also provide significant benefits to their new home.
While the vanguard of the anti-immigrant crusade is found among the likes of the Minutemen and the Tea Party, the native species movement is led by environmentalists, conservationists and gardeners. Despite cultural and political differences, both are motivated — in Margaret Thatcher’s infamous phrase — by the fear of being swamped by aliens.
But just as America is a nation built by waves of immigrants, our natural landscape is a shifting mosaic of plant and animal life. Like humans, plants and animals travel, often in ways beyond our knowledge and control. They arrive unannounced, encounter unfamiliar conditions and proceed to remake each other and their surroundings.
Designating some as native and others as alien denies this ecological and genetic dynamism. It draws an arbitrary historical line based as much on aesthetics, morality and politics as on science, a line that creates a mythic time of purity before places were polluted by interlopers.
What’s more, many of the species we now think of as natives may not be especially well suited to being here. They might be, in an ecological sense, temporary residents, no matter how permanent they seem to us.
These “native” species can have serious effects on their environment. Take the mountain pine beetle: thanks to climate change, its population is exploding in the West, devastating hundreds of thousands of square miles of forest.
It’s true that some non-native species have brought with them expensive and well-publicized problems; zebra mussels, nutria and kudz