Influence of the physical environment and conspecific aggression on the spatial arrangement of breeding grey seals

Understanding the habitat requirements of a species for breeding is essential for its conservation, particularly if the availability of suitable habitat is a limiting factor for population growth. This is postulated to be the case for grey seals, one of the more abundant marine apex predators in northern European waters. In common with similar studies that have investigated the habitat preferences of breeding grey seals, we use abiotic (topographical, climatological) attributes but, unlike previous work, we also incorporate behavioural variables, particularly the occurrence of aggressive interactions between females and the presence of neighbouring seals. We used two Generalized Additive Models (GAM) in a sequential and iterative fashion. The first model links the occurrence of aggression at particular points in the colony to local topography derived from a Geographical Information System (GIS), presence of neighbouring seal pups and the day of the breeding season. The output of this GAM is used as one of the explanatory variables in a GAM of daily variation in the spatial distribution of births. Although proximity of a birth site to a water source and the presence of neighbouring seal pups both had significant influences on the distribution of newborn pups over time and space, at the scale of the study site it was found that simple rules could predict pup distribution more efficiently than a complex individual-based simulation model. (c) 2007 Elsevier B.V. All rights reserved.PostprintPeer reviewe

Toxotherium (Mammalia: Rhinocerotoidea) from Western Jeff Davis County, Texas

Contents: Abstract -- Introduction -- Description -- Discussion -- Acknowledgments -- References CitedA partial right ramus of Toxotherium contains the only known anterior cheek tooth of this genus. The geographic range of this genus is greatly extended by the occurrence of this specimen in Trans-Pecos Texas.Texas Memorial Museu

In praise of unprincipled ethics

In this paper a plea is made for an unprincipled approach to biomedical ethics, unprincipled of course just in the sense that the four principles are neither the start nor the end of the process of ethical reflection. While the four principles constitute a useful "checklist" approach to bioethics for those new to the field, and possibly for ethics committees without substantial ethical expertise approaching new problems, it is an approach which if followed by the bioethics community as a whole would, the author believes, lead to sterility and uniformity of approach of a quite mindbogglingly boring kind. Moreover, much of bioethics is not concerned with identifying the principles or values appropriate to a particular issue, but rather involves analysing the arguments that are so often already in play and which present themselves as offering solutions in one direction or another. Here, as I try to show in discussion of these four scenarios, the principles allow massive scope in interpretation and are, frankly, not wonderful as a means of detecting errors and inconsistencies in argument

On the Kauffman Bracket Skein Module of the Quaternionic Manifold

We use recoupling theory to study the Kauffman bracket skein module of the quaternionic manifold over Z[A(+/- 1)] localized by inverting all the cyclotomic polynomials. We prove that the skein module is spanned by five elements. Using the quantum invariants of these skein elements and the Z(2)-homology of the manifold, we determine that they are linearly independent