Summary: | <p>This thesis examines the patterns in the ground and low-vegetation ant
community of primary lowland dipterocarp forest in Brunei, South East Asia.</p>
<p>The first experimental chapter establishes the importance of ants as the
numerically dominant taxon of the forest floor litter arthropod community, how
many species were found in a hectare of forest, and the probable minimum
asymptotic number of species for each of four sampling methods. The amount
of small fragments of litter is found to vary across the plot, increasing in the
valley, and best explains differences in species richness of samples. Species
richness is highest in the valley. Faunal, rather than microhabitat factors, are
found to be the best predictors of certain litter species' abundance.</p>
<p>Chapter three shows that colony dispersion is not a good method with which
to investigate competition in this habitat at present. The ground dwelling ant
community are more often clumped than over-dispersed, but patterns are
impossible to interpret in the light of ecological theory without knowing the
biology and population dynamics of the species well. I show by reanalysis that
two major flaws in a similar study by Levings and Franks (1982) confound
their claim that overdispersion of ant colonies occurs in Panama. This result has
implications for many other similar studies of spatial dispersion as evidence of
competition.</p>
<p>Chapter four examines whether there is a predictable dominance hierarchy in
the bait responsive species foraging in the litter and on tree trunks. No evidence
of such a hierarchy was found, although significant temporal patterns
unexpected from diel cycles imply avoidance of some species by others.
Differences in recruitment ability were found between tree and ground foraging
species and these correlated with speed to locate and persistence at baits. A
method is offered to test whether ant species are solitary foragers.</p>
<p>Chapter five shows that there is no clear relationship between niche overlaps
and association, i.e. avoidance of colonies or foragers at baits. Low temporal
overlap and high food overlap were found, but did not appear to be related. </p>
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