Studies of spatial representation generally focus on flat environments and visual input. However, the world is not flat, and slopes are part of most natural environments. In a series of 4 experiments, we examined whether humans can use a slope as a source of allocentric, directional information for reorientation. A target was hidden in a corner of a square, featureless enclosure tilted at a 5° ...

The relative importance of facilitation and competition between pairwise plants across abiotic stress gradients as predicted by the stress-gradient hypothesis has been confirmed in arid and temperate ecosystems, but the hypothesis has rarely been tested in tropical systems, particularly across nutrient gradients. The current research examines the interactions between a pioneer shrub Rhodomyrtus...

Tillage erosion is a potential contributor to the total soil erosion occurring within cultivated fields. No study has been carried out on tillage erosion associated with cereal-based production systems, which are the predominant form of crop production in the Canadian Prairies. Previous tillage translocation studies have focused on primary tillage implements (i.e. mouldboard and chisel ploughs)...

The decline of biodiversity with latitude has received great attention, but both the concise pattern and the causes of the gradient are under strong debate. Most studies of the latitudinal gradient comprise only one or few organism types and are often restricted to certain region or habitat types. To test for significant variation in the gradient between organisms, habitats, or regions, a meta-...

report on the syndrome of brain atrophy in girls first described by Andreas Rett2 in Austria, it has become customary to divide the classical course of the disease into four stages.3,4 After the early onset stagnation stage at ⁄2 to 1⁄2 years, there follows the rapid destructive stage lasting weeks to months at one to three years, with stereotypic and autistic features, loss of speech and hand ...

The characteristics of well-developed downslope winds observed by tethered balloon soundings at multiple locations over a low-angle slope in the Salt Lake Valley are studied using the Regional Atmospheric Modeling System (RAMS). The model successfully simulated the key properties of the observed wind and temperature structure and evolution and provided insight into the forcing mechanisms. The r...

0378-1127/$ see front matter Published by Elsevier http://dx.doi.org/10.1016/j.foreco.2012.08.049 ⇑ Corresponding author. Tel.: +1 814 563 1040; fax E-mail address: [email protected] (A.A. Royo). Over the past century, white ash (Fraxinus americana) populations throughout its range have deteriorated as a result of declining tree health and increased mortality rates. Although co-occurring factors ...

Evolutionary ecologists commonly use reaction norms, which show the range of phenotypes produced by a set of genotypes exposed to different environments, to quantify the degree of phenotypic variance and the magnitude of plasticity of morphometric and life-history traits. Significant differences among the values of the slopes of the reaction norms are interpreted as significant differences in p...