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The population dynamics of blowflies (Diptera: Calliphoridae) has been investigated in studies combining different mathematical formalisms, with estimates of demographic parameters and spatial models. However, these applications are limited to laboratory data only. In this study, we investigated the population dynamics of three species of blowflies [Chrysomya albiceps(Wiedemann), Chrysomya megacephala(F.) and Lucilia eximia(Wiedemann)] in a mathematical model that includes parameters estimated in the laboratory and population sizes estimated from field collections, in order to simulate the dynamics of local migration. The model combines experimental estimates of fecundity and survival with abundance data obtained in field collections, to analyze comparatively the population dynamics of the three blowfly species, taking into account the theoretical movement by individuals among municipalities with different urbanization profiles. The ecological patterns of oscillation observed depended on the municipality only for C. albiceps, a species with special demographic characteristics that are probably associated with predatory and cannibalistic behaviors. The bifurcation diagrams showed that intermediate migration rates stabilize populations. Although the proposed model considers only six municipalities in a closed system, the study was able to show different impacts of local migration on the quantitative and qualitative population behaviors, by using different connectivity levels arising from the different distances among areas.

As part of an extensive study in the Portuguese Island population of families with multiple patients suffering from bipolar disorder and schizophrenia, we performed an initial genome-wide scan of 16 extended families with bipolar disorder that identified three regions on chromosomes 2, 11, and 19 with genome-wide suggestive linkage and several other regions, including chromosome 6q, also approached suggestive levels of significance. Dick et al. [2003: Am J Hum Genet 73:107–114] recently reported in a study of 250 families with bipolar disorder a maxLOD score of 3.61 near marker D6S1021 on chromosome 6q. This study replicates this finding having detected a peak NPL = 2.02 (P = 0.025) with the same marker D6S1021(104.7 Mb). Higher-density mapping provided additional support for loci on chromosome 6 including marker D6S1021 with an NPL = 2.59 (P = 0.0068) and peaking at marker D6S1639 (125 Mb) with an NPL = 3.06 (P = 0.0019). A similar pattern was detected with higher-density mapping of chromosome 11 with an NPL = 3.15 (P = 0.0014) at marker D11S1883 (63.1 Mb). Simulations at the density of our fine mapping data indicate that less than 1 scan out of 10 would find two such scores genome-wide in the same scan by chance. Our findings provide additional support for a susceptibility locus for bipolar disorder on 6q, as well as, suggesting the importance of denser scans. Published 2004 Wiley-Liss, Inc.