[Paleopsych] NYT: The Origin of Invasive Species

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The Origin of Invasive Species
New York Times, 5.6.12 (note date)

    By Richard Conniff
    An Odyssey of Ecological Invasion.
    By Alan Burdick.
    Illustrated. 324 pp.
    Farrar, Straus & Giroux. $25.

    FOR the past few years, I have been engaged in hand-to-hand combat
    with a 10-foot-tall alien -- growing thick as toothpicks in a box,
    just outside my door. Late in summer, I thrash through the marsh to
    coat the blades of the phragmites reed with herbicide. (Some
    environmentalists endorse this; others abhor it.) In midwinter, I
    attach a rope to each end of a board and use it to trample down the
    dead stalks. (Politically correct, but Bruegelesque, or possibly
    Chaplinesque.) Sometimes, when I lurch out of the grass, sweating,
    muddy and in a spirit of high ecological dudgeon, my dog, Maggie,
    backs away growling. (''Who is this and what is he doing in my

    Phragmites, a handsome European reed with a feathery crimson plume,
    got dumped on the coast of New England in heaps of 19th-century ship
    ballast. It has choked almost every wetland east of the Mississippi.
    But in my little pocket of coastal marsh, I have opened up the
    landscape again and made room for the native grasses and cattails I
    remember from childhood. I have also made room for nesting mute swans,
    another invader. (Should I coddle the eggs and stop them from
    reproducing? Please do not advise.) I am also acutely aware that if I
    lay off for a season or two, the phragmites will come booming back.
    The natural world has gone wildly astray, through the kindness of
    human beings, and there isn't any good way to put it right again.

    Should we even bother trying? It turns out there are lots of people
    who are obsessed, dismayed and perhaps also occasionally made demented
    by invasive species. Often, they fight noble battles they know they
    are doomed to lose. In ''Out of Eden,'' the science writer Alan
    Burdick travels the world to chronicle their intriguing, undervalued
    lives, and those of the species that trouble them.

    ''The greatest threat to biological diversity is no longer just
    bulldozers or pesticides but, in a sense, nature itself,'' Burdick
    writes. Since its accidental introduction to Guam, the Australian
    brown tree snake has extirpated nine native bird species, sending
    three to extinction. One of the last remaining pairs of another
    species hangs on only because the nest is now barricaded behind
    electric wires, with branches pruned back to keep snakes from creeping
    in from nearby trees: ''The couple looked trapped in its safety, like
    those people in Manhattan who secure their apartments with eight locks
    on the front door.'' Alas, the couple also suffered from ''sexual
    disharmony,'' and small wonder: one night, researchers with traps
    caught seven snakes at the door.

    Because of its knack for hitchhiking in freight containers and
    aircraft landing gear, the brown tree snake may yet set up shop in
    Hawaii or San Diego or even South Florida.

    Thousands of other invasive species, many of them of more benign or
    even beautiful varieties, already surround us. They herald an era of
    ''creeping sameness,'' called by one scientist ''the Homogecene.''
    Tourists freshly escaped from the howling depths of winter may delight
    in the birdsong and the tropical vegetation in Honolulu. But
    everything around them, another scientist tells Burdick, ''is
    introduced'': ''Not a single plant, none of the lowland birds in
    Hawaii are native.'' We are turning the world into ''a McDonald's
    ecosystem,'' with the same species living roughly the same way

    Burdick is best describing the minute details of this change: how does
    the onslaught of new species affect Hawaii's native forests? The
    answer comes partly from studying fruit fly species and obscure soil
    dwellers like springtails and mites that also date back as far as the
    forests. We meet Hawaiian drosophilists who ritually stopper specimen
    vials with torn aloha shirts, to distinguish themselves from
    mainlanders who still use telltale cotton balls. We encounter a
    parasitologist who ''would be more comfortable . . . doing pretty much
    anything other than talking. If he were a bird, he might be a night
    heron . . . liable to stand there blinking in the illumination of a
    flashlight, then dart away.''

    We go underground with a burly entomologist, Frank Howarth, who
    listens to the distinctive love songs sent out by different native
    species of the tiny insects called plant hoppers, which dwell in caves
    and lava tubes. (Howarth once discovered a new species on the property
    of Loretta Lynn and named it Oliarus lorettae, after her.) The plant
    hoppers tap out their songs along the rootlets of a native tree;
    Burdick likens them to human lovers making a crosstown phone call.
    Unfortunately, that tree is being supplanted by an invasive tree
    species with different roots, resulting in something like a
    subterranean silent spring: ''The singers are growing mute,'' Burdick
    writes, ''each one marooned on the island of itself, unable to
    communicate, to mate, to sustain its end of evolutionary

    A KIND of unnatural selection at the hands of introduced species is
    apparently commonplace, with the luckier native species managing to
    survive through accelerated evolution. In 1968, before introduced
    mosquitoes caused a malaria pandemic, some native birds in Hawaii used
    to sleep any which way, leaving themselves exposed to mosquito bites.
    By 1986, those birds had been weeded out, leaving only birds that
    slept with their legs tucked under their bodies, their bills and faces
    buried in the fluffed feathers on their backs. In Australia, toxic
    cane toads introduced from the Americas have favored the proliferation
    of snakes with mouths too small to swallow them.

    Burdick tries to make the case that nature is adaptable enough to
    handle the changes in our topsy-turvy world. When scientists figure
    out how to isolate the problem and interpret all the variables, it
    appears, for instance, that even having 500-pound feral pigs rooting
    through the forests of Hawaii may not do the permanent damage
    conservationists fear. Instead of causing local extinctions, he
    writes, ''most successful invaders simply blend into the ecological
    woodwork. . . . To the local eye, biological diversity seems to have
    increased. Isn't that a good thing?''

    Maybe Burdick is simply trying to avoid the hazards of environmental
    alarmism, but surely this goes too far. It doesn't square with the
    evidence he has diligently accumulated: What about the Australian tree
    spreading rapidly through the Everglades that ''draws in so much water
    through its roots that it essentially converts open marsh habitats . .
    . into . . . dry land''? What about the European green crab, which
    ''single-leggedly crushed the soft-shell clam industry north of Cape
    Cod''? And how about, shortly after a cholera epidemic in South
    America in 1991, ships dumping ballast water that released the same
    strain of cholera bacteria into oyster beds at Mobile Bay in Alabama?
    The argument that many, or even most, invasive species cause no harm
    risks encouraging a ''What, me worry?'' attitude in a public already
    too complacent about environmental change.

    Henry David Thoreau once defined weeding as the business of ''making
    invidious distinctions with the hoe.'' But in the science of
    ''invasion biology,'' the distinctions about what to keep in and what
    to weed out sometimes really matter. Burdick's account of the
    researchers who struggle with this largely thankless work is graceful
    and inviting. He would have written a better book, though, if he had
    made a more cogent case for why, every now and then, we need to cough
    up the money to buy those workers a better hoe.hAndrew Solomon's
    ''Noonday Demon'' received a National Book Award in 2002. He is
    currently writing a book about families grappling with traumatic

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