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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...
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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...
