A global study of forensically significant calliphorids: implications for identification

A proliferation of molecular studies of the forensically significant Calliphoridae in the last decade has seen molecule-based identification of immature and damaged specimens become a routine complement to traditional morphological identification as a preliminary to the accurate estimation of post-mortem intervals (PMI), which depends on the use of species-specific developmental data. Published molecular studies have tended to focus on generating data for geographically localised communities of species of importance, which has limited the consideration of intraspecific variation in species of global distribution. This study used phylogenetic analysis to assess the species status of 27 forensically important calliphorid species based on 1167 base pairs of the COI gene of 119 specimens from 22 countries, and confirmed the utility of the COI gene in identifying most species. The species Lucilia cuprina, Chrysomya megacephala, Ch. saffranea, Ch. albifrontalis and Calliphora stygia were unable to be monophyletically resolved based on these data. Identification of phylogenetically young species will require a faster-evolving molecular marker, but most species could be unambiguously characterised by sampling relatively few conspecific individuals if they were from distant localities. Intraspecific geographical variation was observed within Ch. rufifacies and L. cuprina, and is discussed with reference to unrecognised species.     

Educated guesses: health risk assessment in environmental impact statements

Environmental pollution threatens public health. The search for solutions has advanced the frontiers of science and law. Efforts to protect the environment and public health begin with describing potential adverse consequences of human activities and characterizing the predicted risk. The National Environmental Policy Act requires the preparation of environmental impact statements to describe the effects of proposed federal projects and provide information for agency decisionmakers and the public. Risks to public health are particularly difficult to quantify because of uncertainty about the relation between exposure to environmental contamination and disease. Risk assessment is the current scientific tool to present estimates of risk. The methodology has created controversy, however, when underlying assumptions and uncertainties are not clearly presented. Critics caution that the methodology is vulnerable to bias. This Note evaluates the use of risk assessment in the environmental impact statement process and offers recommendations to ensure informed decisions.     

Forecasts and Preferences in the 1992 General Election

Little attention has been paid to the influence of expectations for victory on the formation of general election preferences in U.S. presidential races. There is good reason to believe, however, that under certain conditions citizens' forecasts of who will win the fall election may influence their preference and their vote. We model preferences during the course of the fall 1992 campaign as a function of two kinds of expectations. First we attempt to identify a component of expectations that is independent of political projection. We discover that expectations based only on information about the race play a prominent role in preference formation early in the fall but decline later as the cost of information drops. Similar results obtain when we include projection in the model of expectations. We conclude that general elections may have some of the same dynamic properties that are observable in primaries. Since early momentum in the fall campaign may influence subsequent preference formation, we contend that leads in early polls are valuable.