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1.
Sub-Antarctic Marion Island has had a permanent research station for 50 years and the islands Wandering Albatrosses have been intensively studied for 20 years. The reactions of breeding birds to approaches by a human on foot were recorded. Three response variables were calculated: intensity of vocal reaction (IVR), intensity of non-vocal reaction (INR) and overall response index (ORI). At 5 m from the nest, twice as many birds stood and/or vocalised as at 15 m. Nearest neighbour distance, age and gender did not explain individual variability of responses. Study colony birds had higher IVR scores than non-study colony birds; birds at colonies closest to the station had the highest ORI scores. A better breeding record was associated with lower IVR and ORI scores, but a causative relationship remains to be demonstrated. A minimum viewing distance of 25 m is recommended for breeding Wandering Albatrosses.
Marienne S. de VilliersEmail: Fax: +27-21-6503434
John CooperEmail:
Peter G. RyanEmail:
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Studies on the effects of a variety of exogenous and anthropogenic environmental factors, including endocrine disruptors, heavy metals, UV light, high temperature, and others, on marine organisms have been presented at the 2nd Bilateral Seminar Italy–Japan held in November 2006. Reports were discussed in order to reveal the current situation of marine ecosystems, aiming at evaluation and prediction of environmental risks.
V. MatrangaEmail:
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The recent contribution by Jarmila Kukalová-Peck on Hennigian phylogenetics and hexapod limb evolution is critically evaluated.
Michael S. Engel (Corresponding author)Email:
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A key point in the analysis of dynamical models of biological systems is to handle systems of relatively high dimensions. In the present paper we propose a method to hierarchically organize a certain type of piecewise affine (PWA) differential systems. This specific class of systems has been extensively studied for the past few years, as it provides a good framework to model gene regulatory networks. The method, shown on several examples, allows a qualitative analysis of the asymptotic behavior of a PWA system, decomposing it into several smaller subsystems. This technique, based on the well-known strongly connected components decomposition, is not new. However, its adaptation to the non-smooth PWA differential equations turns out to be quite relevant because of the strong discrete structure underlying these equations. Its biological relevance is shown on a 7-dimensional PWA system modeling the gene network responsible for the carbon starvation response in Escherichia coli.
Laurent Tournier (Corresponding author)Email:
Jean-Luc GouzéEmail:
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9.
Jablonka and Lamb's claim that evolutionary biology is undergoing a ‘revolution’ is queried. But the very concept of revolutionary change has uncertain application to a field organized in the manner of contemporary biology. The explanatory primacy of sequence properties is also discussed.
Peter Godfrey-SmithEmail:
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One current version of the internalism/externalism debate in evolutionary theory focuses on the relative importance of developmental constraints in evolutionary explanation. The received view of developmental constraints sees them as an internalist concept that tend to be shared across related species as opposed to selective pressures that are not. Thus, to the extent that constraints can explain anything, they can better explain similarity across species, while natural selection is better able to explain their differences. I challenge both of these aspects of the received view and propose a hierarchical view of constraints.
Roger SansomEmail:
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This paper examines the biosemiotic approach to the study of life processes by fashioning a series of questions that any worthwhile semiotic study of life should ask. These questions can be understood simultaneously as: (1) questions that distinguish a semiotic biology from a non-semiotic (i.e., reductionist–physicalist) one; (2) questions that any student in biosemiotics should ask when doing a case study; and (3) still currently unanswered questions of biosemiotics. In addition, some examples of previously undertaken biosemiotic case studies are examined so as to suggest a broad picture of how such a biosemiotic approach to biology might be done.
Donald FavareauEmail:
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12.
Threatened species and the spatial concentration of humans   总被引:1,自引:1,他引:0  
Public policies that encourage high-density human living arrangements have been predicated explicitly on the assumption that certain spatial distributions of a fixed-size human population are less environmentally damaging than others. We examine the empirical validity of this assumption across 127 countries by analyzing whether the concentration of human presence in each country is related statistically to the percentage of species that were on the IUCN Red List in 2004. Our findings indicate that concentration of the human population is associated with reduced imperilment among amphibians but increased imperilment among reptiles, and birds.
Ram PanditEmail:
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I show that gene regulation networks are qualitatively consistent and therefore sufficiently similar to linearly seperable connectionist networks to warrant that the connectionist framework be applied to gene regulation. On this view, natural selection designs gene regulation networks to overcome the difficulty of development. I offer some general lessons about their evolvability that can be learned by examining the generic features of connectionist networks.
Roger SansomEmail:
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There is a continuing controversy over Native American fishing and hunting rights. We show that Native American (Menominee) and European American fish experts have a common knowledge base and share values and attitudes associated with fishing practices (though organized around different ethical principles). Nonetheless, perceived group differences are dramatic (especially European American perceptions of Native Americans). Cultural differences in models of nature and associated inference processes appear to mediate these stereotypes and may hold the key to reducing intergroup conflict over resources.
Douglas MedinEmail:
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We construct a mapping from complex recursive linguistic data structures to spherical wave functions using Smolensky’s filler/role bindings and tensor product representations. Syntactic language processing is then described by the transient evolution of these spherical patterns whose amplitudes are governed by nonlinear order parameter equations. Implications of the model in terms of brain wave dynamics are indicated. Electronic supplementary material  The online version of this article (doi: ) contains supplementary material, which is available to authorized users.
Peter beim GrabenEmail:
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Anonymous communications in the Internet   总被引:1,自引:0,他引:1  
With the growth and acceptance of the Internet, there has been increased interest in maintaining anonymity in the network. By using traffic analysis, it is possible to infer who is talking to whom over the Internet. We present a novel approach to hide the senders and the receivers of messages. Routes are chosen and frames traverse these routes. Each frame consists of a token and a node can send a message through a frame only when the corresponding token is free. The advantage of our protocol is that it poses limited bandwidth overhead when there is at least some traffic, while posing minimal bandwidth overhead when there is no traffic at all.
Arjan DurresiEmail:
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Evolutionary developmental biology (Evo-Devo) is a new and rapidly developing field of biology which focuses on questions in the intersection of evolution and development and has been seen by many as a potential synthesis of these two fields. This synthesis is the topic of the books reviewed here. Integrating Evolution and Development (edited by Roger Sansom and Robert Brandon), is a collection of papers on conceptual issues in Evo-Devo, while From Embryology to Evo-Devo (edited by Manfred Laubichler and Jane Maienschein) is a history of the problem of the relations between ontogeny and phylogeny.
Stavros IoannidisEmail:
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19.
Debates over adaptationism can be clarified and partially resolved by careful consideration of the ‘grain’ at which evolutionary processes are described. The framework of ‘adaptive landscapes’ can be used to illustrate and facilitate this investigation. We argue that natural selection may have special status at an intermediate grain of analysis of evolutionary processes. The cases of sickle-cell disease and genomic imprinting are used as case studies.
Peter Godfrey-SmithEmail:
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This paper provides a legal overview of key issues associated with donation of genetic samples and information from a donor perspective. In particular, it addresses the property status of samples as well as issues in respect of consent, privacy, commercialisation and benefit sharing. The paper highlights the need for appropriate protection and safeguards for individuals, but also, importantly, for understanding what donors actually think and want in terms of genetic research and the use of their samples and information. The paper seeks to emphasise the importance of transparency and accountability in the conduct of research in order to maximise donor participation and confidence and public trust in general.
Margaret OtlowskiEmail:
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