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The Rural Voice, 1988-01, Page 28AGRICULTURAL RESEARCH PART THREE: BAD RESEARCH The Good, the Bad, the Ugly, and the Incomprehensible T here is a piece of informa- tion included in the Ontario Ministry of Agriculture and Food's "factsheet" on army worms that is incorrect. The error is not earth -shattering, nor does it have any effect on other information in the sheet, but it is an interesting example of how the scientific system can fail. In the section describing the insect's life cycle, the insects that appear in the second summer are said to have over -wintered as a mature caterpillars or pupae, thereby starting the new generation in the spring. In fact, at no stage in its life is this insect able to withstand the degree of cold encountered in a Canadian winter, and the entire generation dies off. A spring migration of adults from the southern U.S. and northern Mexico brings the army worms back into Canada for the next season. To understand how there can be two versions of one insect's life cycle, we need to go back 100 years or so to the early days of entomology in Canada. When the life cycle of the army worm in Canada was first worked out, scientists observed larvae in the fall and adult moths in the spring. There seemed to be only one explanation: the insect over -wintered as a larva or pupa. The scientists did not imagine that moths migrated, so that explanation was never considered. Later, people wanting life-cyle information on the army worm used the reports published by these scien- tists. The facts in the reports were never verified experimentally — the explanation was too sensible to be questioned — and became the stan- dard version of events. Once there is a standard version, it gains a life of its own, and it is very difficult to get out by Ian Wylie-Toal of people's minds. So as more information was gathered about the insect, inconsistencies were explained away within the conventional model. Eventually, however, enough evidence was accumulated for a second theory, that the insects blew in every year from the U.S. The two theories were informally debated for decades. Eventually, someone got around to testing whether or not army worms could survive the winter, and discovered they could not. Simultane- ously, evidence for a migratory theory developed for the black cutworm seemed to fit the army worm, and there was a rapid reassessment. The orthodox explanation was dropped by the scientists, but is holding on in non- scientific publications. There are several noteworthy aspects of this little story. The first is how much science depends on previ- ous research. If every aspect of a problem had to be researched anew by every researcher, very little new work would get done. Instead, scientists take published "facts" and proceed from that point. This means that faulty information could be used as a source for new research, generating a whole series of faulty facts. Science has done as much as it can to minimize this risk. All research papers are scrutinized by other scien- tists before they're published, and are rejected if the methods used, the anal- ysis of the data, or the conclusions drawn are not acceptable. But of course this system is not perfect. Older papers published before vigor- ous review became common still circulate. And incorrect analyses can slip by even the most rigorous review. Mistakes can also arise out of the review process itself, when reviewers reject true but unorthodox findings because the findings don't conform to conventional belief. A scientist who does not believe moths migrate will be very critical of a paper that suggests they do, and will find ways to pick the paper apart and scuttle it. There are many instances of radical but basically true explanations being stalled for years. To overcome human reluctance in the face of change, new theories usually must have overwhelming and irrefutable evidence to support them. The second interesting thing about the story is why it took so long to test whether or not the moths could sur- vive cold weather. After all, research has been conducted on army worms for more than a century, and the over- wintering habits have been debated for at least 25 years. Why, then, was the testing of controversial aspects of the life cycle done only in the late 1970s? The answer lies in the economic structure of scientific work. In Can- ada, as in much of the world, a scien- tist's status is determined by the num- ber of papers published, the quality of the journals accepting them, and the originality of the research. The issue of originality, though minor compared to the other two, does have an effect on research. A scientist who merely repeats old work is looked 26 THE RURAL VOICE