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1.
This paper discusses the persistent devaluation of the girl child in India and the link between the entrenched perception of female valuelessness and the actual practice of infanticide of girl babies or foetuses. It seeks to place female infanticide, or ‘gendercide,’ within the context of Western-derived conceptions of ethics, justice and rights. To date, current ethical theories and internationally purveyed moral frameworks, as well as legal and political declarations, have fallen short of an adequate moral appraisal of infanticide. This paper seeks to rethink the issue.
Renuka M. SharmaEmail:
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2.
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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3.
The Freshwater Animal Diversity Assessment (FADA) project aims at compiling an overview of genus- and species-level diversity of animals in the continental, aquatic ecosystems of the world. It is a collective effort of 163 experts, and presents 59 articles treating the diversity and endemism of different animal taxa, ranging from microscopic worms to mammals, at global and regional scales. Given their structural importance, an article on macrophytes is also added. Here, we give an overview of the project’s history, and outline the common framework of the various articles, as well as the conventions the experts agreed to adhere to in their treatises. Furthermore, we briefly introduce future prospects.
E. V. BalianEmail:
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4.
This paper introduces a threshold policy with hysteresis (TPH) for the control of one-predator one-prey models. The models studied are the Lotka–Volterra and Rosenzweig–MacArthur two species density-dependent predator–prey models and the Arditi–Ginzburg nondimensional ratio-dependent model. The proposed policy (TPH) changes the dynamics of the system in such a way that a bounded oscillation is achieved confined to a region that does not allow extinction of either species. The policy can be designed by a suitable choice of so called virtual equilibrium points in a simple and intuitive manner.
Amit Bhaya (Corresponding author)Email:
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5.
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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6.
Paleoenvironmental and archaeological investigations from the ’Ewa Plain of O’ahu provide insight into the problem of understanding lowland native forest loss in Hawai’i. Data from pollen analysis of a pond core record, avian paleontology, and archeology, document a precipitous decline of the native forest starting before Polynesian settlement on the ’Ewa Plain but after Polynesian colonization of O’ahu. It is hypothesized that rats, introduced by Polynesian colonizers, increased exponentially in the absence of significant predators or competitors, feeding on a largely endemic vegetation that had evolved in the absence of mammalian predators. Rats radiated ahead of human colonizers on O’ahu, eating their way through the vegetation, perhaps before the colonizers had encountered much of the pristine lowland forest into which the rats had radiated. This hypothesis is supported by several observations, including the almost complete absence of extinct or extirpated avian faunal remains in archaeological deposits, the present distribution of endemic vegetation in Hawai’i, rat ecology, population biology, and other evidence.
J. Stephen AthensEmail:
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Lévy Flights in Dobe Ju/’hoansi Foraging Patterns   总被引:1,自引:0,他引:1  
We analyzed data on Ju/’hoansi hunter–gatherer foraging patterns and found that their movements between residence camps can be modeled as a Lévy flight. The step lengths of their movements scale as a power law with an exponent μ = 1.97. Their wait times (residence times) at the camps also scale as a power law (μ = 1.45). A Lévy flight with step lengths μ = 2 is an optimal search pattern for scarce, randomly located targets; thus, the Ju/’hoansi foraging pattern may approach an optimal search in this area of sparse plant and animal resources. These findings affect the application of optimal foraging theory to humans in anthropology and archaeology because they alter the way in which search and travel times should be quantified. These results may also carry implications for the study of other patterns of human movement, such as demic diffusion and migration.
Clifford T. BrownEmail:
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11.
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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12.
Anthropologists and psychiatrists traditionally have used the salience of a mind–body dichotomy to distinguish Western from non-Western ethnopsychologies. However, despite claims of mind–body holism in non-Western cultures, mind–body divisions are prominent in non-Western groups. In this article, we discuss three issues: the ethnopsychology of mind–body dichotomies in Nepal, the relationship between mind–body dichotomies and the hierarchy of resort in a medical pluralistic context, and, finally, the role of mind–body dichotomies in public health interventions (biomedical and psychosocial) aimed toward decreasing the stigmatization of mental illness. We assert that, by understanding mind–body relations in non-Western settings, their implications, and ways in which to reconstitute these relations in a less stigmatizing manner, medical anthropologists and mental health workers can contribute to the reduction of stigma in global mental health care.
Brandon A. KohrtEmail:
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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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16.
T. Ryan Gregory 《Evolution》2008,1(3):259-273
The occurrence, generality, and causes of large-scale evolutionary trends—directional changes over long periods of time—have been the subject of intensive study and debate in evolutionary science. Large-scale patterns in the history of life have also been of considerable interest to nonspecialists, although misinterpretations and misunderstandings of this important issue are common and can have significant implications for an overall understanding of evolution. This paper provides an overview of how trends are identified, categorized, and explained in evolutionary biology. Rather than reviewing any particular trend in detail, the intent is to provide a framework for understanding large-scale evolutionary patterns in general and to highlight the fact that both the patterns and their underlying causes are usually quite complex.
T. Ryan GregoryEmail:
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17.
This paper is an interpretation and defense of Richard Levins’ “The Strategy of Model Building in Population Biology,” which has been extremely influential among biologists since its publication 40 years ago. In this article, Levins confronted some of the deepest philosophical issues surrounding modeling and theory construction. By way of interpretation, I discuss each of Levins’ major philosophical themes: the problem of complexity, the brute-force approach, the existence and consequence of tradeoffs, and robustness analysis. I argue that Levins’ article is concerned, at its core, with justifying the use of multiple, idealized models in population biology.
Michael WeisbergEmail:
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18.
Event-related brain potentials (ERP) are important neural correlates of cognitive processes. In the domain of language processing, the N400 and P600 reflect lexical-semantic integration and syntactic processing problems, respectively. We suggest an interpretation of these markers in terms of dynamical system theory and present two nonlinear dynamical models for syntactic computations where different processing strategies correspond to functionally different regions in the system’s phase space.
Peter beim GrabenEmail:
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19.
The discussion of the adaptive landscape in the philosophical literature appears to be divided along the following lines. On the one hand, some claim that the adaptive landscape is either “uninterpretable” or incoherent. On the other hand, some argue that the adaptive landscape has been an important heuristic, or tool in the service of explaining, as well as proposing and testing hypotheses about evolutionary change. This paper attempts to reconcile these two views.
Anya PlutynskiEmail:
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20.
Equilibrium phase diagrams of the ι-carrageenan/maltodextrin/water system have been established at potassium chloride (KCl) concentrations of 0.1, 0.2, and 0.3 M and 80, 85 and 90°C. All pseudo-binary phase diagrams of ι-carrageenan/maltodextrin mixtures suggested classic segregative phase separation. The binodal was heavily skewed toward the maltodextrin axis. The high asymmetry of the ι-carrageenan/maltodextrin/water phase diagram determined by the phase-volume-ratio method was consistent with the compositional analysis of phase-separated ι-carrageenan/maltodextrin samples and can be explained in terms of the Flory–Huggins interaction parameter, reflecting a higher water-binding ability of the charged ι-carrageenan than neutral maltodextrin. Increasing the concentration of ι-carrageenan-gel-promoting KCl from 0.1 to 0.3 M at 80°C enlarged the two-phase domain, whereas increasing temperature from 80 to 90°C at 0.3 M KCl enhanced biopolymer compatibility. The effects of salt concentration and temperature have been related to the differences in the Flory–Huggins interaction parameters of the two biopolymers with water as well as the helix formation of ι-carrageenan in the presence of KCl through the changes in the slopes of tie lines of phase-separated samples.
Gregory R. Ziegler (Corresponding author)Email:
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