Many alien plants use animal vectors for dispersal of their diaspores (zoochory). If alien plants interact with native disperser animals, this can interfere with animal-mediated dispersal of native diaspores. Interference by alien species is known for frugivorous animals dispersing fruits of terrestrial plants by ingestion, transport and egestion (endozoochory). However, less attention has been...

Genetic divergence among populations of marine broadcast spawners in the absence of past geological barriers presents an intriguing challenge to understanding speciation in the sea. To determine how differences in life history affect genetic divergence and demographic histories across incomplete dispersal barriers, we conducted a comparative phylogeographic study of three intertidal limpets (Si...

Seed dormancy and endozoochorous dispersal have important effects on population dynamics, i.e. seed bank formation, spatial and temporal bethedging, avoidance of crowding and decreased sib-competition. Seeds having primary dormancy do not germinate, even if adequate environmental and dispersal conditions are met, until an after-ripening period is completed. This study examined the effects on ge...

We show that the size of the smallest depth-two N -superconcentrator is Θ(N log N/ log logN). Before this work, optimal bounds were known for all depths except two. For the upper bound, we build superconcentrators by putting together a small number of disperser graphs; these disperser graphs are obtained using a probabilistic argument. For obtaining lower bounds, we present two different method...

A Boolean function f :F2 → F2 is called an affine disperser of dimension d, if f is not constant on any affine subspace of F2 of dimension at least d. Recently Ben-Sasson and Kopparty gave an explicit construction of an affine disperser for sublinear d. The main motivation for studying such functions comes from extracting randomness from structured sources of imperfect randomness. In this paper...

For plants dispersed by frugivores, spatial patterns of recruitment are primarily influenced by the spatial arrangement and characteristics of parent plants, the digestive characteristics, feeding behaviour and movement patterns of animal dispersers, and the structure of the habitat matrix. We used an individual-based, spatially-explicit framework to characterize seed dispersal and seedling fat...

Hunting can change abundances of vertebrate seed predators and seed dispersers, causing species-specific changes in seed dispersal and seed predation and altering seedling communities. What are the consequences of these changes for the adult plant community in the next generation and beyond? Here, I derive equations showing how reduced seed dispersal reduces plant reproduction by intensifying k...

The influence of the golden lion tamarin (Leontopithecus rosalia) as a seed disperser was studied by monitoring two groups of tamarins from December 1998 to December 2000 (871.9 hours of observations) in a forest fragment in south-east Brazil. The tamarins consumed fruits of 57 species from at least 17 families. They ingested the seeds of 39 species, and 23 of these were put to germinate in the...

Recently, the ideal free dispersal strategy has been proven to be evolutionarily stable in the spatially discrete as well as continuous setting. That is, at equilibrium a species adopting the strategy is immune against invasion by any species carrying a different dispersal strategy, other conditions being held equal. In this paper, we consider a two-species competition model where one of the sp...

Competition and colonization are two mechanisms that are important for determining coexistence and species diversity in spatially structured habitats. However, these mechanisms may not be independent as species can exhibit behavioral or physiological changes in response to competition that alters their colonization rates. This study examines the effect of interspecific interactions on the colon...