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1.
Rabal‐Garcés, R., Cuenca‐Bescós, G., Canudo, J.I. & de Torres, T. 2011: Was the European cave bear an occasional scavenger? Lethaia, Vol. 45, pp. 96–108. The cave bear Ursus spelaeus fossils remains are quite abundant in the Late Pleistocene site of Coro Tracito (Huesca, Spain). The site constitutes the highest mountain record of cave bears in the Iberian Peninsula. Being a monospecific locality, it permits the study of the biology and dietary habits of this species. The study of the limb bones established first, the mortality pattern of this population of Ursus spelaeus and, second, the alteration pattern due to carnivore tooth‐marks. Some authors have performed similar analyses in the same kind of skeletal elements in other cave bear localities all over Europe and, therefore it has been possible to compare our results with those from other sites. The tooth‐marks found in the bones of cave bears, especially in monospecific sites, have been attributed to a scavenging behaviour. In agreement with the authors, our analysis presented here supports the hypothesis of scavenging behaviour for cave bears. □Behaviour, Late Pleistocene, Spain, taphonomy, tooth‐marks, Ursus spelaeus.  相似文献   

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Cave bears (Ursus deningeri and U. spelaeus) and hominids (Homo heidelbergensis, H. neanderthalensis, and H. sapiens) were potential competitors for environmental resources (subterranean and open air). Here, we examined the age at death of cave bear (Ursus spelaeus Rosenmüller-Heinroth) specimens from Amutxate cave in order to shed light on the effect of resource sharing between cave bears and hominids. After studying dental wear of the deciduous and permanent dentitions, the ontogenetic development of mandibles, and incremental layers of cement (annuli), we defined five age groups differentiated by marked development and size gaps. Our findings indicate that after hibernating, bears abandoned the den, thereby leaving the subterranean environment (caves) free for temporary hominid occupation-this would explain the subtle traces of hominid presence in many dens. However, a simple calculation based on age at death of subadult and adult cave bear specimens in Amutxate cave, extrapolated to the whole cave area, showed that the area surrounding this cave hosted bears for at least 9,000 years. This length of habitation, quite similar to the time-span derived from amino acid racemization and electron spin resonance, indicates that bear populations in the Amutxate cave constituted a serious constraint for hominid exploitation of the environment.  相似文献   

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Our ageing society is confronted with a dramatic increase in incidence of age-related neurodegenerative diseases; biomedical research leading to novel therapeutic strategies is crucial to address this problem. Animal models of neurodegenerative conditions are invaluable in improving our understanding of the molecular basis of pathology, potentially revealing novel targets for intervention. Here, we review transgenic animal models of Alzheimer’s and Parkinson’s disease reported in mice, zebrafish, Caenorhabditis elegans and Drosophila melanogaster. This information will enable researchers to compare different animal models targeting disease-associated molecules by genomic engineering and to facilitate the development of novel animal models for any particular study, depending on the ultimate research goals.  相似文献   

4.
Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour–disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour–parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour–parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained.  相似文献   

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《Journal of thermal biology》2001,26(4-5):249-253
(1) Primordial lesioning and stimulation experiments established a thermoregulatory centre in the rostral brain stem at the end of the 19th century. (2) A major landmark in understanding how deep-body temperature (Tc) is sensed, came in 1912 when Barbour found that changing rostral brain stem temperature inversely raised or lowered Tc, ultimately leading to a mono-centric concept of hypothalamic thermoregulation, prevailing for about 50 years. (3) The discovery of extrahypothalamic sites of temperature signal generation in the 1960s led to the multiple-input, multiple-controller concept of thermoregulation. (4) During the last 40 years, concepts concerning thermosensory specificity have radically changed from viewing bimodal peripheral thermoreceptors and hypothalamic thermoreceptors as the only relevant signal generators towards a complex picture including monomodality of peripheral warm and cold thermoreceptors and multimodality of deep-body thermosensors.  相似文献   

8.
In 1996, a link was identified between Friedreich’s ataxia (FRDA), the most common inherited ataxia in men, and alterations in the gene encoding frataxin (FXN). Initial studies revealed that the disease is caused by a unique, most frequently biallelic, expansion of the GAA sequence in intron 1 of FXN. Since the identification of this link, there has been tremendous progress in understanding frataxin function and the mechanism of FRDA pathology, as well as in developing diagnostics and therapeutic approaches for the disease. These advances were the subject of the 4th International Friedreich’s Ataxia Conference held on 5th–7th May in the Institut de Génétique et de Biologie Moléculaire et Cellulaire, Illkirch, France. More than 200 scientists gathered from all over the world to present the results of research spanning all areas of investigation into FRDA (including clinical aspects, FRDA pathogenesis, genetics and epigenetics of the disease, development of new models of FRDA, and drug discovery). This review provides an update on the understanding of frataxin function, developments of animal and cellular models of the disease, and recent advances in trying to uncover potential molecules for therapy.  相似文献   

9.
This article examines the combined influence of cognitions (i.e., impact beliefs) and affect (i.e., feelings) on normative beliefs (i.e., support for management options) about wolves and brown bears. Data were obtained from stratified random face-to-face interviews (n = 1,611). The survey was conducted in the Abruzzo Lazio and Molise National Park (central Italy), where people have a long history of coexistence with large carnivores. Knowledge was hypothesized to moderate the relationships of beliefs and feelings on support for management actions. Path analyses supported the role of affect in mediating perceived impact beliefs and support for the protection of large carnivores. Knowledge moderated these relationships in the case of wolves but not brown bears. Residents of the national park had more knowledge about bears than wolves, which might partly explain both the stronger effect that knowledge had on the affective component and its lack of a moderating effect on the bear model. Overall, our findings show the positive attitude of residents toward large carnivores and support the idea of affect being more important than cognition in predicting normative beliefs.  相似文献   

10.
Few actors have had a greater impact on the “framing of Muslims” as a social and political “problem” in Norway since 2001 than Hege Storhaug of the government- and corporate billionaire funded civil society organization Human Rights Service (HRS). Using the methodological tools of the “rhetorical branch” of Critical Discourse Analysis (CDA), and applying the Aristotelian concepts of ethos, logos and pathos, we analyze the bestselling popular title on Islam and Muslims ever published in Norway, namely Storhaug’s self-published 2015 title “Islam – The Eleventh Plague”. We argue that Storhaug’s popular success must be understood in light of her rhetorical appeals to femonationalism, the critique of religion and “Enlightenment” values. We show how she in her writings incites fear of the Muslim “Other” through specific rhetorical devices and a positioning of herself as a defender of the “nation” and the “people” – against national and international “elites”.  相似文献   

11.
Wielkopolska (western Poland) is a region, with good reason, called the main food base of Poland. All indices of agricultural production have always been there (since 19th century) much higher than elsewhere in the country (Ratajczak 1977/1978, Buszko 1984, Gorzelak 1989, Czyzewski et al. 1992; table 1). Such a situation had a beneficial effect on the amount of the income generated by a family of Wielkopolska and, thus, decided on its better financial status. Additionally, rural inhabitants of this region have always been characterised by a more advantageous educational structure in comparison with people of other Polish villages. Generally, it is easy to detect the relationship between the life standard, the level of education and family planning. The aim of this paper is to assess fertility of women from villages of Wielkopolska in the period of transformation of the political and economic system in Poland.  相似文献   

12.
The National Center for Biotechnology Information (NCBI) organizes information resources for life scientists on an evolutionary scheme. This facilitates research about present-day organisms. The recent discovery of a new arenavirus, the LUJO virus, illustrates the utility of adopting evolution as a central architectural principle for life sciences databases: using the NCBI’s resources, clinicians were able to classify the new virus in real time—soon enough to aid in the diagnosis and treatment of a hemorrhagic fever caused by the LUJO virus. Topics fundamental to the study of evolution, often thought of as useless, are indeed vital because they inform how life science information ought to be organized.  相似文献   

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That holobionts (microbial communities and their animal or plant hosts) are units of selection squares poorly with the observation that microbes are often recruited (horizontally acquired) from the environment, not passed down vertically from parent to offspring, as required for collective reproduction. The taxonomic makeup of a holobiont’s microbial community may vary over its lifetime and differ from that of conspecifics. In contrast, biochemical functions of the microbiota and contributions to host biology are more conserved, with taxonomically variable but functionally similar microbes recurring across generations and hosts. To save what is of interest in holobiont thinking, we propose casting metabolic and developmental interaction patterns, rather than the taxa responsible for them, as units of selection. Such units need not directly reproduce or form parent-offspring lineages: their prior existence has created the conditions under which taxa with the genes necessary to carry out their steps have evolved in large numbers. These taxa or genes will reconstruct the original interaction patterns when favorable conditions occur. Interaction patterns will vary (for instance by the alteration or addition of intermediates) in ways that affect the likelihood of and circumstances under which such reconstruction occurs. Thus, they vary in fitness, and evolution by natural selection will occur at this level. It is on the persistence, reconstruction, and spread of such interaction patterns that students of holobiosis should concentrate, we suggest. This model also addresses other multi-species collectively beneficial interactions, such as biofilms or biogeochemical cycles maintaining all life.  相似文献   

15.
Classic toxin-induced animal models of Parkinson’s disease: 6-OHDA and MPTP   总被引:19,自引:0,他引:19  
Neurological disorders in humans can be modeled in animals using standardized procedures that recreate specific pathogenic events and their behavioral outcomes. The development of animal models of Parkinsons disease (PD) is important to test new neuroprotective agents and strategies. Such animal models of PD have to mimic, at least partially, a Parkinson-like pathology and should reproduce specific features of the human disease. PD is characterized by massive degeneration of dopaminergic neurons in the substantia nigra, the loss of striatal dopaminergic fibers and a dramatic reduction of the striatal dopamine levels. The formation of cytoplasmic inclusion bodies (Lewy bodies) in surviving dopaminergic neurons represents the most important neuropathological feature of PD. Furthermore, the massive striatal dopamine deficiency causes easily detectable motor deficits in PD patients, including bradykinesia, rigidity, and resting tremor, which are the cardinal symptoms of PD. Over the years, a broad variety of experimental models of PD were developed and applied in diverse species. This review focuses on the two most common classical toxin-induced PD models, the 6-hydroxy-dopamine (6-OHDA model) and the 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) model. Both neurotoxins selectively and rapidly destroy catecholaminergic neurons, whereas in humans the PD pathogenesis follows a progressive course over decades. This discrepancy reflects one important and principal point of weakness related to most animal models. This review discusses the most important properties of 6-OHDA and MPTP, their modes of administration, and critically examines advantages and limitations of selected animal models. The new genetic and environmental toxin models of PD (e.g. rotenone, paraquat, maneb) are discussed elsewhere in this special issue.This work was supported by grants from the Deutsche Forschungsgemeinschaft.  相似文献   

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The past 25 years have seen significant advances in understanding the diversity and functions of glycoprotein glycans in Drosophila melanogaster. Genetic screens have captured mutations that reveal important biological activities modulated by glycans, including protein folding and trafficking, as well as cell signaling, tissue morphogenesis, fertility, and viability. Many of these glycan functions have parallels in vertebrate development and disease, providing increasing opportunities to dissect pathologic mechanisms using Drosophila genetics. Advances in the sensitivity of structural analytic techniques have allowed the glycan profiles of wild-type and mutant tissues to be assessed, revealing novel glycan structures that may be functionally analogous to vertebrate glycans. This review describes a selected set of recent advances in understanding the functions of N-linked and O-linked (non-glycosaminoglycan) glycoprotein glycans in Drosophila with emphasis on their relatedness to vertebrate organisms.  相似文献   

18.
Almost all the knowledge now produced about psychiatry includes what is called “the patient’s or client’s perspective.” This paper analyzes how this notion has been framed in the discourses on mental health over the last two decades, particularly in mental health research and in anthropology. The very concept of the “patient’s perspective” is a social and historical construct. Despite its remarkable prevalence, the notion remains vague. Mental health research pictures it as a stable attribute of the individual. Anthropologists integrate the contextual nature of the patient view; but they still largely envision the psychiatric patient as a rational actor producing narratives based on common sense. However, in psychiatric practice, the client’s perspective is not something the patient individually produces; it is rather shaped by and in a context. To explore this process, my research investigated interactions between staff and patients in a French community mental health center, and showed that the client’s perspective is the result of a collective process. Further analysis demonstrates that eliciting or producing the patient’s view is sometimes considered a therapeutic goal in itself, since being granted the status of a rational and narrative actor gives access to the most valued model of care, one that is based on partnership. Being an outcome that is negotiated between patients and care providers, the “patient’s view” then becomes a new resource in mental health settings.
Livia VelpryEmail:
  相似文献   

19.
Elephant populations are in decline across the African continent, but recent aerial surveys show that populations in Uganda are increasing. However, threats such as poaching and habitat disturbance remain. Having a comprehensive knowledge of the ranging behaviour of Ugandan elephants is crucial to understanding where critical habitat for the species occurs. We investigated various aspects of ranging behaviour of 45 radio-collared elephants (Loxodonta africana) in three areas—Queen Elizabeth Protected Area (QEPA), Murchison Falls (MFPA) Protected Area and Kidepo Valley (KVCA) Conservation Area. We also set Ugandan analyses in a continental context by comparison with home ranges reported in published literature. Elephants within KVCA had larger core ranges than elephants in QEPA or MFPA. Wet season ranges in KVCA were much larger than dry season ranges. The most important core areas in all three national parks were centred around water resources. Home range size was negatively correlated with net primary productivity (NPP) at Ugandan (N = 39 individuals) and continental (N = 17 sites) scales. This study indicates that, at a local scale, factors such as water source location are important in shaping elephant ranging behaviour. At larger scales, factors such as NPP are good predictors of elephant home range size.  相似文献   

20.
The barn owl (Tyto alba) is capable of capturing prey by passive hearing alone, guided by a topographic map of auditory space in the external nucleus of its inferior colliculus. The neurons of this auditory space map have discrete spatial receptive fields that result from the computation of interaural differences in the level (ILD) and time-of-arrival (ITD) of sounds. Below we review the synthesis of the spatial receptive fields from the frequency-specific ITDs and ILDs to which the neurons are tuned, concentrating on recent studies exploiting virtual auditory space techniques to analyze the contribution of ILD. We then compared the owls spatial discrimination, assessed behaviorally, with that of its space map neurons. Spatial discrimination was assessed using a novel paradigm involving the pupillary dilation response (PDR), and neuronal acuity was assessed by measuring the changes in firing rate resulting from changes in source location, scaled to the variance. This signal-detection-based approach revealed that the change in the position of the neural image on this map best explains the spatial discrimination measured using the PDR. We compare this result to recent studies in mammalian systems.  相似文献   

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