American Scientist 

About: American Scientist is an academic journal published by Sigma Xi. The journal publishes majorly in the area(s): Cancer & Population. It has an ISSN identifier of 0003-0996. Over the lifetime, 2113 publications have been published receiving 85564 citations. The journal is also known as: American Scientists.

Biological invasions as global environmental change

Abstract: In recent years the difficult question "what constitutes scientific misconduct?" has troubled prominent ethicists and scientists and tied many a blue-ribbon panel in knots. In teaching an ethics class for graduate and undergraduate students over the past few years, we have identified what seems to be a necessary starting point for this debate: the clearest possible understanding of how science actually works. Without such an understanding, we believe, one can easily imagine formulating plausible-sounding ethical principles that would be unworkable or even damaging to the scientific enterprise.

The strategy of model building in population biology

Abstract: what were previously independent clusters of more or less co herent theory. Population genetics and population ecology, the most mathematical areas of population biology, had developed with quite different assumptions and techniques, while mathematical biogeography is essentially a new field. For population genetics, a population is specified by the frequencies of genotypes without reference to the age distribution, physiological state as a reflection of past history, or population density. A single population or species is treated at a time, and evolution is usually as sumed to occur in a constant environment. Population ecology, on the other hand, recognizes multispecies sys tems, describes populations in terms of their age distributions, phys iological states, and densities. The environment is allowed to vary but the species are treated as genetically homogeneous, so that evolution is ignored. But there is increasing evidence that demographic time and evolu tionary time are commensurate. Thus population biology must deal simultaneously with genetic, physiological, and age heterogeneity within species of multispecies systems changing demographically and evolving under the fluctuating influences of other species in a heterogeneous environment. The problem is how to deal with such a complex system. The naive, brute force approach would be to set up a mathematical model which is a faithful, one-to-one reflection of this complexity. This would require using perhaps 100 simultaneous partial differential equa tions with time lags; measuring hundreds of parameters, solving the equations to get numerical predictions, and then measuring these pre dictions against nature. However: (a) there are too many parameters to measure; some are still only vaguely defined; many would require a lifetime each for their measurement.