The Janzen-Connell (JC) hypothesis provides a conceptual framework for explaining the maintenance of tree diversity in tropical forests. Its central tenet-that recruits experience high mortality near conspecifics and at high densities-assumes a degree of host specialization in interactions between plants and natural enemies. Studies confirming JC effects have focused primarily on spatial distri...

Many large-seeded Neotropical trees depend on a limited guild of animals for seed dispersal. Fragmented landscapes reduce animal abundance and movement, limiting seed dispersal between distant forest remnants. In 2006, experimental plantings were established in pasture to determine whether plantings enhance seed dispersal and, ultimately, seedling recruitment. We examined patterns of naturally ...

Competition for seeds has a major influence on the evolution of granivores and the plants on which they rely. The complexity of interactions and coevolutionary relationships vary across forest types. The introduction of non-native granivores has considerable potential to alter seed dispersal dynamics. Non-native species are a major cause of endangerment for native species, but the mechanisms ar...

While seed source selection is an important initial step in the genetic improvement of Christmas trees, continuously returning to seed collections from natural stands precludes any further improvement in genetic quality. In addition, the genetic variation within most seed sources is tremendous and varies from year to year. In order for the Christmas tree industry to move past the current level ...

The complex interplay between species along environmental gradients ultimately shapes their distributions and additional community interactions. Ant-mediated seed dispersal fails in the wettest habitat of deciduous forest in eastern North America, and we examine whether this pattern corresponds with colony distributions for seed-dispersing ants and associated heterogeneity in abiotic and bioti...

the damages due to dwarf mistletoes to the industrial forests encouraged the scientists to evaluate the infection intensity and illustrate the spatial distribution of mistletoes for forest management, wild life and biodiversity conservation. there are two current systems to evaluate infection intensity wich are easier, cheaper, more efficient and authoritative than others in all over the world,...

Although agriculture is often listed as a major threat to tropical biodiversity conservation, researchers are starting to rethink this view by examining traditional forest gardens that have been adapted for modern crops like coffee and cacao. These unique farming systems incorporate habitat for birds and other biodiversity that may make them a useful addition to integrated conservation strategi...

Slash-and-burn agriculture is a sequence of interactions between farmers and ecosystems, which includes forest, cropping, fallow, and cropping after fallow. In sampling across this sequence in Pucallpa, Peru, 235 plant species were recorded in the forest, of which 143 were not found in any successive land use. However, plants not occurring in the forest colonized fields and fallow. In total, 59...

Seed mass is an adaptive trait affecting species distribution, population dynamics and community structure. In widely distributed species, variation in seed mass may reflect both genetic adaptation to local environments and adaptive phenotypic plasticity. Acknowledging the difficulty in separating these two aspects, we examined the causal relationships determining seed mass variation to better ...

BACKGROUND Functional redundancy has been debated largely in ecology and conservation, yet we lack detailed empirical studies on the roles of functionally similar species in ecosystem function. Large bodied frugivores may disperse similar plant species and have strong impact on plant recruitment in tropical forests. The two largest frugivores in the neotropics, tapirs (Tapirus terrestris) and m...