Most environmental protection issues concern the often chronic exposure of large populations to low doses of chemical toxins and ionizing radiation. However, measuring the effects of low doses on populations exposed over long time periods is highly problematic. Politically driven opinions often tend to take the place of science. Part of the problem is that epidemiology is a weak tool when the level of exposure is low. High background levels of exposure, genetic diversity, and exposure uncertainties all contribute to “noise” and make dose-response relationships difficult to define. Uncertainty feeds anxiety, leading to polarized politics. This review looks at the promise of molecular technologies for identifying the effects of low doses of radiation and identifies some of the issues involved in defining risk after low-dose exposures. While the main pollutant discussed in this article is ionizing radiation, the analysis could apply equally well to other toxic exposures or to combined radiation and chemical pollutants.

Using phenotypes to explore and describe biological diversity has become less popular than using genetics to do so. Results from the two approaches often conflict at the species level and below, the very ground floor of biodiversity. However, because in today's data sets phenotypic divergence is probably driven mostly by selection and genetic divergence by stochastic processes, we should not expect them to be tightly coupled at population-to-species evolutionary depths. For heuristic purposes it is useful to consider phenotypic and genetic data as largely unidimensional axes in an inherently multidimensional process, and this is perhaps the source of the controversies surrounding each approach. Phenotypic andgenotypic data sets might give very different portrayals of evolutionary trajectories in adaptive and nonadaptive space. Integrating these data sets provides a roadmap for theoretical and empirical research. The exploration of the multidimensional relationships of the two types of differentiation in diverging populations is providing important insights both into the units of biodiversity and into the processes responsible for their generation.

Biological field stations and marine laboratories (FSMLs) serve as places to study the natural environment in a variety of ways, from the level of the molecule to the globe. Undergraduate opportunities at FSMLs reflect the diversity of study options—formal courses, research and service internships, and field-trip experiences—and students are responding to those opportunities: More than half of the FSMLs that responded to an informal survey indicated an increase in their undergraduate enrollment in the past 10 years. Many programs are residential in nature, which facilitates the development of a community of scholars in which undergraduates can interact not just with their peers but also with graduate students, research assistants, postdoctoral fellows, and resident and visiting faculty. With respect to undergraduates, challenges for FSMLs include maintaining relevance in curricular offerings, attracting rigorous and well-trained instructors, providing adequate numbers of mentors for research experiences, and providing funding to assist undergraduates who want to study at a FSML.

The decimation of aquatic wildlife through overexploitation is usually perceived as a marine phenomenon, yet it has also been common in freshwater ecosystems. Fish and other aquatic animals were superabundant when Europeans first arrived in North America and Australia, and were intensively exploited soon after. Contemporaneously, the construction of barriers in rivers increasingly prevented many species from migrating. Populations usually crashed as a result. Natural resource managers have not fully considered the ecological impacts of the devastation of these species to the environmental degradation that we see today, yet these impacts are likely to be pervasive. Nor have resource managers embedded the role of these species in river restoration. We argue that the functions of these depleted stocks need to be considered and perhaps reestablished if river restoration efforts are to be successful. The establishment of freshwater protected areas may be the most effective way to do this.

Landsliding is a complex process that modifies mountainscapes worldwide. Its severe and sometimes long-lasting negative effects contrast with the less-documented positive effects on ecosystems, raising numerous questions about the dual role of landsliding, the feedbacks between biotic and geomorphic processes, and, ultimately, the ecological and evolutionary responses of organisms. We present a conceptual model in which feedbacks between biotic and geomorphic processes, landslides, and ecosystem attributes are hypothesized to drive the dynamics of mountain ecosystems at multiple scales. This model is used to integrate and synthesize a rich, but fragmented, body of literature generated in different disciplines, and to highlight the need for profitable collaborations between biologists and geoscientists. Such efforts should help identify attributes that contribute to the resilience of mountain ecosystems, and also should help in conservation, restoration, and hazard assessment. Given the sensitivity of mountains to land-use and global climate change, these endeavors are both relevant and timely.

Ecology is a leading discipline in the synthesis of diverse knowledge. Ecologists have had considerable experience in bringing together diverse, multinational data sets, disciplines, and cultural perspectives to address a wide range of issues in basic and applied science. Now is the time to build on this foundation and invest in ecological synthesis through new national or international programs. While synthesis takes place through many mechanisms, including individual efforts, working groups, and research networks, centers are extraordinarily effective institutional settings for advancing synthesis projects.