The continuous model of Anderson et al. (1981), Nature 289, 765-771, is successful in describing certain characteristics of rabies epizootics, in particular, the secondary recurrences which follow the initial outbreak; however, it also predicts the occurrence of exponentially small minima in the infected population, which would realistically imply extinction of the virus. Here we show that incl...

Many of the mechanisms underlying density-dependent regulation of populations, including contest competition and disease spread, depend on contact among neighboring animals. Understanding how variation in population density influences the frequency of contact among neighboring animals is therefore an important aspect to understanding the mechanisms underlying, and ecological consequences of, de...

The ability to detect the incursion of an invasive species or destroy the last individuals during an eradication program are some of the most difficult aspects of invasive species management. The presence of foxes in Tasmania is a contentious issue with recent structured monitoring efforts, involving collection of carnivore scats and testing for fox DNA, failing to detect any evidence of foxes....

Social learning is often assumed to help young animals respond appropriately to potential threats in the environment. We brought wild, juvenile jackdaws briefly into captivity to test whether short exposures to conspecific vocalizations are sufficient to promote anti-predator learning. Individuals were presented with one of two models-a stuffed fox representing a genuine threat, or a toy elepha...

Although Superintendent of Lingfield Colony for 30 years, Dr. Fox was always firm in his belief that colony life was only essential for a minority of patients, and even for them that it should only be regarded as a period for stabilization and drug adjustment. It was one of his greatest satisfactions that the last 10 or 15 years showed such startling changes in drug therapy. He often said that ...

In this paper we describe RAPOSA, a question answering system for Portuguese, and we present detailed results of the participation in the QA@CLEF 2007 evaluation task. We explain how we improved our system since the last participation in QA@CLEF, by expanding the set of rules associated with Question Parsing and Answering Extraction. We will finish by pointing lines for future work, and by intr...

The Forkhead or Fox gene family encodes putative transcription factors. There are at least four Fox genes in yeast, 16 in Drosophila melanogaster (Dm) and 42 in humans. Recently, vertebrate Fox genes have been classified into 17 groups named FoxA to FoxQ. Here, we extend this analysis to invertebrates, using available sequences from D. melanogaster, Anopheles gambiae (Ag), Caenorhabditis elegan...