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This paper examines the relationship between per capita income and a wide range of environmental indicators using cross-country panel sets. The manner in which this has been done overcomes several of the weaknesses asscociated with the estimation of environmental Kuznets curves (EKCs). outlined by Stern et al. (1996). Results suggest that meaningful EKCs exist only for local air pollutants whilst indicators with a more global, or indirect, impact either increase monotonically with income or else have predicted turning points at high per capita income levels with large standard errors – unless they have been subjected to a multilateral policy initiative. Two other findings are also made: that concentration of local pollutants in urban areas peak at a lower per capita income level than total emissions per capita; and that transport-generated local air pollutants peak at a higher per capita income level than total emissions per capita. Given these findings, suggestions are made regarding the necessary future direction of environmental policy.

Abstract. Using raw geographic distributions for Neotropical species and subspecies of the perching birds (Order Passeriformes), we present an hypothesis of area‐relationships for twelve avian areas of endemism in the lowland Neotropics. With 1717 characters (distributions of species and subspecies) we find a single most parsimonious tree of area‐relationships. This topology does not match area‐relationships determined from phylogenetic studies of morphologic characters in some Neotropical birds. Analyses of data partitions representing major taxonomic subdivisions within Passerine birds provide many different hypotheses of area‐relationships. These results suggest that a single set of Neotropical area‐relationships is not likely. In the future, we suggest greater emphasis be placed on research to document patterns in the Neotropics, particularly phylogenetic patterns, than on speculation about what processes have been important for diversification.

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Avian host life history traits have been hypothesized to predict rates of infection by haemosporidian parasites. Using molecular techniques, we tested this hypothesis for parasites from three haemosporidian genera (Plasmodium, Haemoproteus, and Leucocytozoon) collected from a diverse sampling of birds in northern Malawi. We found that host life history traits were significantly associated with parasitism rates by all three parasite genera. Nest type and nest location predicted infection probability for all three parasite genera, whereas flocking behavior is an important predictor of Plasmodium and Haemoproteus infection and habitat is an important predictor of Leucocytozoon infection. Parasite prevalence was 79.1% across all individuals sampled, higher than that reported for comparable studies from any other region of the world. Parasite diversity was also exceptionally high, with 248 parasite cytochrome b lineages identified from 152 host species. A large proportion of Plasmodium, Haemoproteus, and Leucocytozoon parasite DNA sequences identified in this study represent new, previously undocumented lineages (n = 201; 81% of total identified) based on BLAST queries against the avian malaria database, MalAvi.