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It is far too early to begin to create products for food or medicines or to grow them in open fields at this stage in biotechnology's evolution if we wish to avoid unexpected and unpredictable consequences. But because the driving force to get novel organisms out is money, when I say such things I am confronted with angry biotechnologists demanding to know when we will ever know that a genetically engineered product is ready to be consumed or grown in the open.

My response is that when a field of experimentation is immature, virtually every bit of research yields a surprise and ultimately a publication; last time I looked, there was a profusion not only of articles but of biotechnology journals. The science is in its infancy. When it has reached a point where an exact sequence of DNA can be synthesized or isolated and inserted at a specific sequence in a recipient's DNA and the resultant phenotype predicted beforehand with absolute accuracy and replicability, then the science is mature enough to proceed to the next stages of wider testing. We're a long way from that. The science is exciting, but the applications are frightening in view of our ignorance.

I deliberately stopped research but did not immediately lose all of the knowledge that made me a geneticist. I am proud of my career and contribution in the field, yet the minute I ceased doing research and began to speak out about the unseemly haste with which scientists were rushing to exploit their work, people in biotechnology lashed out as if somehow I no longer understood what is being done.

It is young people, relatively unencumbered by distractions like administration and teaching, who are able to expend the energy to do research. As scientists get older, they acquire layers of responsibility that take them away from the bench. There is always the pull to keep publishing to validate their standing as scientists. It is unfortunate that older scientists aren't afforded recognition and respect for their past achievements and acknowledged as elder statespeople who can afford to look at the broader picture.

THE POWER OF SCIENCE is in description, teasing out bits of nature's secrets. Each insight or discovery reveals further layers of complexity and interconnections. Our models are of necessity absurdly simple, often grotesque caricatures of the real world. But they are our best tool when we try to “manage” our surroundings. In most areas, such as fisheries, forestry, and climate, our goal should be simply to guide human activity. Instead of trying to bludgeon nature into submission by the brute-force applications of our insights (if planted, seedlings will grow into trees; insecticides kill insects), we would do better to acknowledge the 3.8 billion years over which life has evolved its secrets. Rather than overwhelming nature, we could try to emulate what we see, and that “biomimicry” should be our guiding principle.

But even reductionism — focusing on parts of nature — can provide stunning insights into the elegance and interconnectedness of nature, and reveal the flaws in the way we try to manage her.

A good illustration of both the strengths and weaknesses of science and its application is the temperate rain forest of North America. Pinched between the Pacific Ocean and the coastal mountain range, this rare ecosystem extends from Alaska to northern California. Around the world, temperate rain forests are a tiny part of the terrestrial portion of the planet, yet they support the highest biomass of any ecosystem on Earth. That's because there are large trees like Sitka spruce, Douglas fir, red and yellow cedar, hemlock, and balsam. But the heavy rains wash nutrients from the soil, making it nitrogen poor. How, then, can it support the immense trees that characterize the forest? For several years, the David Suzuki Foundation funded studies to answer this question by ecologist Tom Reimchen of the University of Victoria.

Terrestrial nitrogen is almost exclusively 14N, the normal isotope of nitrogen; in the oceans, there is a significant amount of 15N, a heavier isotope that can be distinguished from 14N. Throughout the North American temperate rain forest, salmon swim in thousands of rivers and streams. The five species of salmon need the forest, because when the forest around a salmon-bearing watershed is clear-cut, salmon populations plummet. That's because the fish are temperature sensitive; a small rise in temperature is lethal, so salmon need the shade of the canopy that keeps water temperatures down. In addition, the tree roots cling to the soil to prevent it from washing into the spawning gravels, and the forest community provides food for the baby salmon as they make their way to the ocean. But now we are finding that there is a reciprocal relationship — the forest also needs the salmon.

Along the coast, the salmon go to sea by the billions. Over time, they grow as they incorporate 15N into all their tissues. By the time they return to their natal streams, they are like packages of nitrogen fertilizer marked by 15N. Upon their return to spawn, killer whales and seals intercept them in the estuaries, and eagles, bears, and wolves, along with dozens of other species, feed on salmon eggs and on live and dead salmon in the rivers. Birds and mammals load up on 15N and, as they move through the forest, defecate nitrogen-rich feces throughout the ecosystem.

Bears are one of the major vectors of nitrogen. During the salmon runs, they congregate at the rivers to fish, but once a bear has seized a fish, it leaves the river to feed alone. A bear will move up to 150 yards away from the river before settling down to consume the best parts — brain, belly, eggs — then return to the river for another. Reimchen has shown through painstaking observation that in a season, a single bear may take from six hundred to seven hundred salmon. After a bear abandons a partially eaten salmon, ravens, salamanders, beetles, and other creatures consume the remnants. Flies lay eggs on the carcass, and within days, the flesh of the fish becomes a writhing mass of maggots, which polish off the meat and drop to the forest floor to pupate over winter. In the spring, trillions of adult flies loaded with 15N emerge from the leaf litter just as birds from South America come through on their way to the nesting grounds in the Arctic.

Reimchen calculates that the salmon provide the largest pulse of nitrogen fertilizer the forest gets all year, and he has demonstrated that there is a direct correlation between the width of an annual growth ring in a tree and the amount of 15N contained within it. Government records of salmon runs over the past fifty years show that large rings occur in years of big salmon runs. When salmon die and sink to the bottom of the river, they are soon coated with a thick, furry layer of fungi and bacteria consuming the flesh of the fish. In turn, the 15N-laden microorganisms are consumed by copepods, insects, and other invertebrates, which fill the water and feed the salmon fry when they emerge from the gravel.

In dying, the adult fish prepare a feast on which their young may dine on their way to the ocean. Thus, the ocean, forest, northern hemisphere and southern hemisphere form a single integrated part of nature held together by the salmon. For thousands of years, human beings were able to live on this productivity and achieve the highest population density of any non-agrarian society, as well as rich, diverse cultures.

When Europeans occupied these lands, they viewed the vast populations of salmon as an opportunity to exploit for economic ends. Today in Canada the responsibility for the salmon is assigned to the Department of Fisheries and Oceans for the commercial fishers, to the Department of Indian and Northern Affairs for the First Nations food fishery, and to provincial ministers of tourism for the sport fishers. There are enormous conflicts between the ministries, even though they are responsible for the same “resource,” because their respective constituencies have very different needs. The whales, eagles, bears, and wolves come under the jurisdiction of the minister of the environment, and trees are overseen by the minister of forests. The mountains and rocks are the responsibility of the minister of mining, and the rivers may be administered by the minister of energy (for hydroelectric power) or the minister of agriculture (for irrigation). In subdividing the ecosystem in this way, according to human needs and perspectives, we lose sight of the interconnectedness of the ocean, forest, and hemispheres, thereby ensuring we will never be able to manage the “resources” sustainably.