When aliens attack

This may rock your world if you're the holistic New Age type, or for that matter if you believe in God. But whether or not you admire the tone of his language, Burdick is trying to get to an essential problem, which could be framed in a variety of ways: Do we want to live in a world where everything is familiar, or a world where many things remain strange, alien, even completely unknown? God or evolution or the turning of the cosmic wheel has empowered human beings to make this choice, and if we choose the latter option -- which is less convenient and more difficult to manage -- then why?

Hawaiian entomologist David Foote, one of Burdick's star witnesses, tells him that human life all over the world is increasingly accompanied by a handful of plants and animals we all know: domestic animals and livestock; scavenger species like squirrels, coyotes and raccoons; a few familiar shrubs and trees; rats, pigeons, sparrows, roaches. "If that's what you want to live with -- a small suite of a dozen, maybe two dozen species -- then you can live with that, I suppose. You can argue that biodiversity has a utilitarian value. But it's an aesthetic issue for me."

It's extraordinary to hear a scientist -- let alone one whose professional career has largely been devoted to the genus Drosophila, the fruit flies -- fall back on aesthetics. But what could more clearly define the separation, partial and conditional as it may be, between man and nature? As another scientist points out, you could also call this a moral or a spiritual question, but whatever it is, you can't quantify it by collecting data or see it under a microscope. Burdick is struck by the idea "that the strongest argument for preserving biodiversity might rest on something so mercurial, so subjective, so intimate as a personal desire to live in a world that is biologically rich."

In a sense, Burdick's journey along the cutting edge of ecological science points us back in time, to the early years of the environmental movement and the old-fashioned sentiment that wilderness preservation had psychic and spiritual benefits for human beings, irrespective of its meaning for "nature." No one ever put it better than novelist Wallace Stegner, in his 1960 "Wilderness Letter":

"Something will have gone out of us as a people if we ever let the remaining wilderness be destroyed; if we permit the last virgin forests to be turned into comic books and plastic cigarette cases; if we drive the few remaining members of the wild species into zoos or to extinction; if we pollute the last clean air and dirty the last clean streams and push our paved roads through the last of the silence, so that never again will Americans be free in their country from the noise, the exhausts, the stinks of human and automotive waste. And so that never again can we have the chance to see ourselves single, separate, vertical and individual in the world, part of the environment of trees and rocks and soil, brother to the animals, part of the natural world and competent to belong in it. Without any remaining wilderness we are committed wholly, without chance for even momentary reflection and rest, to a headlong drive into our technological termite-life, the Brave New World of a completely man-controlled environment."

Amid all Burdick's amusing and amazing factoids (there's a Hawaiian leaf-hopper named in honor of country singer Loretta Lynn; the London Underground is home to not one but three distinct species of mosquito), his appealing portraits of nerd-hero scientists (one exclaims in wonder: "These Balanus improvisus have just released nauplii into my sample!"), his brain-stretching vocabulary (not just "nauplii," but also "propagule," "reticule" and "stochasticities"), his taxonomic lists and his sometimes overly rhapsodic asides on the circular life cycle of the barnacle or the mating habits of the sea scallop, one moment stood out for me.

Burdick's only encounter with the dreaded brown tree snake of Guam comes when an animal control officer presents him with a captured 6-foot specimen (despite its prevalence on the island, the snake is notoriously difficult to find in the wild). The snake wraps itself around him, "squeezing with a gentle, almost clinical indifference, like the blood pressure gauge in a doctor's office." Burdick becomes aware of the obvious difference between them -- "I could both consider the snake and consider my considering of the snake, whereas the snake could only consider me as lunch."

Beyond that, Burdick finds himself gripped by a perverse admiration. "The snake was a marvelous work of biology -- powerful, elegant, efficient," he writes. "As agents of homogenization go, it was not without appeal. I sympathized with it. I even felt a little sorry for it -- guileless, cursed, outcast."

Next Page: Is nature finished?

• View blog reactions