News News

Random placement models can predict species–area relationships

Species–area relationships are the product of many ecological processes and their interactions. Explanations for the species–area relationship (SAR) have focused on separating putative niche-based mechanisms that correlate with area from sampling effects caused by patches with more individuals containing more species than patches with fewer individuals. The hypothesis that SARs in breeding waterfowl communities are caused by sampling effects was tested (i.e. random placement from the regional species pool). Consistent with the sampling effects hypothesis, observed SARs were accurately predicted by null models, which randomly allocated ducks to ponds, in three different years and for diving and dabbling duck guilds. This is the first demonstration that null models can predict SARs in waterbirds or any other aquatic organisms. Observed patterns of species association, however, were not well predicted by null models as in all years there was less observed segregation among species (i.e. more aggregation) than under the random expectation, suggesting that intraspecific competition could play a role in structuring duck communities. Taken together, results indicate that when emergent properties of ecological communities such as the SAR appear to be caused by random processes, analyses of species associations can be critical in revealing the importance of niche-based processes (e.g. competition) in structuring ecological communities. informacion[at]ebd.csic.es Bidwell et al (2014) Random placement models predict species–area relationships in duck communities despite species aggregation. Oikos DOI: 10.1111/oik.00821


http://onlinelibrary.wiley.com/doi/10.1111/oik.00821/abstract;jsessionid=6F2916A7C768D81F95C94CAA9594794D.f04t04
Average (0 Votes)

Latest News Latest News

Models for human porphyrias: Have animals in the wild been overlooked?

Humans accumulate porphyrins in the body mostly during the course of porphyrias, diseases caused by defects in the enzymes of the heme biosynthesis pathway and that produce acute attacks, skin...

Combined effects of global change on bumblebees

The decline in bee populations has recently attracted much attention from researchers, conservationists and the general public, with insect-mediated pollination being a key process for terrestrial...

Artificial light at night as a driver of urban colonization

Urbanization and artificial light at night (ALAN) are major drivers of local biodiversity losses causing community alterations, disruption of predator-prey interactions, and ultimately, promotion...

A new subspecies of Manx shearwater to the Canary Islands

The taxonomy of Procellariiformes, particularly petrels and shearwaters, is still unresolved. The Manx shearwater Puffinus puffinus is one of the best studied seabirds worldwide. Most of the...

For a better production, agriculture areas need to recover at least 20% of natural habitat

International agreements aim to conserve 17% of Earth’s land area by 2020 but include no area-based conservation targets within the working landscapes that support human needs through farming,...