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Most bird species inhabiting mangroves are considered visitors to the habitat. However, some species feed or reproduce almost exclusively in mangroves. If most are visitors, then the question arises as to whether bird communities characteristic of mangroves actually exist. Similarly, the influence of adjacent vegetation types on avifaunal composition in mangroves remains unassessed. In this study, I address these questions, providing fundamental information regarding the avifaunas of New World mangroves. I surveyed avifaunas at nine sites in Mexico and El Salvador. Mangroves were traversed principally by canoe, and on foot when possible. For each area, species presence, type of vegetation, and use of mangroves for perching, nesting, rearing young, or feeding were recorded. Three principal methods were used to complete inventories of th...
When one considers the Contras—the forces that opposed the Sandinista government of Nicaragua—the natural propensity is to view these forces as a monolithic institution. The purpose of this thesis is to draw a clear distinction between the Contras that were based in Honduras and the Southern Opposition Front (SOF) that was based in Costa Rica; more than geography separated these two fronts that opposed the FSLN government in the Contra War. In order to draw this distinction, this thesis will first offer a chronology of the Southern Front from its beginnings in 1980 through the declared cessation of hostilities in 1988. Following this, the reasons why the SOF came into existence will be examined through the application of the Collapsible Pyramid Model as presented by Jan Knippers Black and by reviewing the motivation behind US foreign p...
This dissertation examines gender and ethnic identities in the Mi ski to community of Kuri and in the Rio Platano Biosphere Reserve (RPBR), a pluri-ethnic protected area on the Miskito Coast of Honduras. The study is based on long-term field research consisting of participant observation, interviews, and the collection of ethnic terms of reference, songs, and incantations. The research focuses on how Miskito identities are constructed, maintained, and negotiated as viewed through the eyes of the Kuri women. The central research problem combines instrumentalist and constructivist approaches with ethnicity and gender theory in an effort to explore how Miskito individuals use situational identities to gain access to scarce resources in their homeland. The results show how the control of resources affects the types of identities that Miski...
This dissertation tests the hypothesis of differential fertility of Hb AS females in a malarial environment. The biocultural factors that affect achieved reproduction in this sample are examined. The aim of the research is to document the action of natural selection through differential fertility, and the interaction of culture and biology to produce achieved fertility. Epidemiological, clinical and in vitro studies indicate that Hb AS individuals experience low malarial morbidity and mortality. Thus, natural selection increases the frequency of hemoglobin S through differential mortality when the selective agent is malaria. However, it has also been proposed (Livingston, 1957) that the high frequency of hemoglobin S in malarial environments may be the result of differential mortality and reproduction. Pirscheinfs work (1961, 1984) sug...
A phylogenetic analysis of morphological characters revealed that the species content of the Bufo valliceps group is limited to eight species (two of them new) occurring between the southern United States and Costa Rica. Several Middle American species usually associated with this group are shown to be closely related, but outside of the Bufo valliceps group. The monotypic genus Crepidophryne is placed in the synonymy of Bufo. The taxon Bufo valliceps macrocristatus is recognized as a species distinct from Bufo valliceps. Seven species in the Bufo valliceps group appear to be allopatric with respect to one another and are restricted to humid primary forest habitat on the lower slopes of the major mountain ranges of southern Mexico, Guatemala, Honduras, and Costa Rica. The species Bufo valliceps is widespread in humid lowland habitats f...
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