首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 156 毫秒
1.
This essay examines how selected Christian doctrines may inform contemporary environmental ethics. Particular attention is focused on the doctrines of creation, redemption and eschatology. The ethical models of dominion, stewardship, and co-creatorship are developed based on these theological doctrines. It is also argued that these ethical models must be explicitly rooted in the church's biblical, creedal and theological tradition if they are to influence the values, virtues and practices of the church. The applicability of these models as resources for developing a public environmental ethic is also assessed.  相似文献   

2.
In Tunisia, even though it is an Arab-Muslim country, the teaching of evolution is not forbidden. Nevertheless, the Muslim perspective makes learning about the biological basis of evolution difficult because of the harmony that exists between religion and science. Tunisian students have a mixed misconception: They explain the diversity of life as both a result of God’s works and a result of evolutionary processes at the same time. This paper presents the external evaluation that assesses the impact of an approach to teaching evolution designed to help students distinguish between theological and biological (scientific) explanations. The comparative analysis between the outcomes of the pre- and post-teaching interviews shows some success in helping students to distinguish between the two types of arguments and to develop better understanding of evolution as scientific knowledge.  相似文献   

3.
Although the health hazards of smoking are now generally accepted in most Western countries, the arguments have not had much impact on poorer nations. A conference on tobacco control held in Harare, Zimbabwe, in November last year was the largest to tackle this problem. The conference heard how threats of epidemics of tobacco related disease in the distant future held little weight with governments of countries that often already had massive public health problems. More immediate effects needed to be emphasised. Speakers gave three cogent arguments; firstly, the loss of capacity for foreign trade in essential goods, since most African countries are net importers of tobacco; secondly, the extensive deforestation which is occurring to fuel the flue curing of tobacco; thirdly, evidence from Papua New Guinea that raising taxation on tobacco provides governments with increased income for many years before a decrease begins.  相似文献   

4.
Dawson A 《Bioethics》2005,19(1):72-89
There are many different ethical arguments that might be advanced for and against childhood vaccinations. In this paper I explore one particular argument that focuses on the idea that such vaccinations are justifiable because they are held to be in the best interests of a particular child. Two issues arise from this idea. The first issue is how best interests are to be determined in this case. The second issue is what follows from this to justify potential interventions within the family in relation to such vaccinations. I argue that best interests must be characterised objectively in such situations and that this means that, in at least some cases, parental decision-making about vaccinating their children may be overridden.  相似文献   

5.
Arthropods have evolved various adaptations to survive adverse seasons and it has long been discussed why some arthropods are freezing-susceptible and some are freezing-tolerant. However, which mode of frost resistance came first during the course of evolution? A commonly held opinion is that no choice of strategy has been offered in evolution, because each species of arthropod may have its own evolutionary and natural history, leading to cold-hardiness. Freezing tolerance is more frequent in holometabolous insect orders and partially used by certain vertebrates, like some terrestrially hibernating amphibians and reptiles. Supported by phylogenetic, ontogenetic and ecological arguments, we suggest here that freezing tolerance is more recent than freezing susceptibility in the course of arthropods evolution. In addition, we observe that three basic modes of freezing resistance in insect species exist in the field: (i) permanent or year-round freezing-susceptible species, (ii) alternative or seasonal freezing-susceptible/freezing-tolerant species, (iii) permanent or year-round freezing tolerant species.  相似文献   

6.
Dawson A 《Bioethics》2005,19(2):188-205
There are many different ethical arguments that might be advanced for and against childhood vaccinations. In this paper I will explore one particular argument that focuses on the idea that childhood vaccinations are justifiable because they are held to be in the best interests of a particular child. Two issues arise from this idea. The first issue is how best interests are to be determined in the case of childhood vaccinations. The second issue is what follows from this to justify potential interventions within the family in relation to such vaccinations. I argue that best interests must be characterised objectively in such situations and that this means that, in at least some cases, parental decision-making about vaccinating their children may be overridden.  相似文献   

7.
Tobias Hainz 《Bioethics》2015,29(7):507-515
The application of enhancement technologies to children and non‐medical infant male circumcision are both topics that enjoy the continuous attention of bioethical research but are usually discussed in isolation from each other. Yet one can show that three major arguments used by opponents of the enhancement of children are also applicable to circumcision. These arguments are based on the insecurity of these procedures, the child's right to an open future, and human nature as a foundation of human dignity. People who reject the enhancement of children because of these arguments but accept circumcision hold mutually inconsistent moral convictions or apply double moral standards to these cases. This is particularly important when legislative systems treat the enhancement of children and circumcision in a considerably different manner, which is true for many contemporary legislative systems. At least three strategies can be adopted in order to avoid such inconsistencies, two of which, however, fail for various reasons. According to a third, more promising strategy, circumcision should be subsumed under human enhancement and treated like other enhancement technologies. This strategy justifies restrictions on, but not the prohibition of circumcision. Furthermore, proponents of circumcision should be prepared for future technologies that provide similar benefits as circumcision but are not as contentious as this intervention, so that, in the future, circumcision could become more and more unacceptable.  相似文献   

8.
The traditional view that species are held together through gene flow has been challenged by observations that migration is too restricted among populations of many species to prevent local divergence. However, only very low levels of gene flow are necessary to permit the spread of highly advantageous alleles, providing an alternative means by which low-migration species might be held together. We re-evaluate these arguments given the recent and wide availability of indirect estimates of gene flow. Our literature review of F(ST) values for a broad range of taxa suggests that gene flow in many taxa is considerably greater than suspected from earlier studies and often is sufficiently high to homogenize even neutral alleles. However, there are numerous species from essentially all organismal groups that lack sufficient gene flow to prevent divergence. Crude estimates on the strength of selection on phenotypic traits and effect sizes of quantitative trait loci (QTL) suggest that selection coefficients for leading QTL underlying phenotypic traits may be high enough to permit their rapid spread across populations. Thus, species may evolve collectively at major loci through the spread of favourable alleles, while simultaneously differentiating at other loci due to drift and local selection.  相似文献   

9.
Is DNA variation maintained in organelle genomes selectively neutral? The answer to this question has important implications for many aspects of ecology and evolution. While traditionally the answer has been ‘yes’, recent studies in animals have shown that, on the contrary, mitochondrial DNA polymorphism is frequently adaptive. In plants, however, the neutrality assumption has not been strongly challenged. Here, we begin with a critical evaluation of arguments in favour of this long‐held view. We then discuss the latest empirical evidence for the opposing prediction that sequence variation in plant cytoplasmic genomes is frequently adaptive. While outstanding research progress is being made towards understanding this fundamental topic, we highlight the need for studies that combine information ranging from field experiments to physiology to molecular evolutionary biology. Such an interdisciplinary approach provides a means for determining the frequency, drivers and evolutionary significance of adaptive organelle DNA variation.  相似文献   

10.
Abstract.— Certain arguments concerning the evolution of eusociality form a classic example of the application of the principles of kin selection. These arguments center on the different degrees of relatedness of potential beneficiaries of an individual's efforts, for example a female's higher relatedness to her sisters than to her daughters in a haplodiploid system. This type of reasoning is insufficient to account for the evolution and maintainence of sexual reproduction, because parthenogenic females produce offspring that are more closely related to them than are offspring produced sexually. Among the forces invoked to explain sexual reproduction is deleterious mutation. This factor can be shown to favor eusociality as well, because siblings produced by helping carry fewer deleterious alleles on average than would offspring. The strength of this effect depends on the genomewide deleterious mutation rate, U, and on the selection coefficient, s, associated with deleterious alleles. For small s, the effect depends approximately on the product Us. This phenomenon illustrates that an assumption implicit in some analyses–that the relatedness of an individual to an actor is all that matters to its value to that actor–can fail for the evolution of eusociality as it does for the evolution of sex.  相似文献   

11.
Heavey P 《Bioethics》2013,27(1):36-47
Some religious believers may see synthetic biology as usurping God's creative role. The Catholic Church has yet to issue a formal teaching on the field (though it has issued some informal statements in response to Craig Venter's development of a 'synthetic' cell). In this paper I examine the likely reaction of the Catholic Magisterium to synthetic biology in its entirety. I begin by examining the Church's teaching role, from its own viewpoint, to set the necessary backround and context for the discussion that follows. I then describe the Church's attitude to science, and particularly to biotechnology. From this I derive a likely Catholic theology of synthetic biology. The Church's teachings on scientific and biotech research show that it is likely to have a generally positive disposition to synbio, if it and its products can be acceptably safe. Proper evaluation of, and protection against, risk will be a significant factor in determining the morality of the research. If the risks can be minimized through regulation or other means, then the Church is likely to be supportive. The Church will also critique the social and legal environment in which the research is done, evaluating issues such as the patenting of scientific discoveries and of life.  相似文献   

12.
We revisit the issue of the emergence of fair behavior in the framework of the spatial Ultimatum game, adding many important results and insights to the pioneering work by Page et al. [2000. The spatial Ultimatum game. Proc. R. Soc. London B 267, 2177], who showed in a specific example that on a two-dimensional setup evolution may lead to strategies with some degree of fairness. Within this spatial framework, we carry out a thorough simulation study and show that the emergence of altruism is a very generic phenomenon whose details depend on the dynamics considered. A very frequent feature is the spontaneous emergence and fixation of quasiempathetic individuals, whose offers are very close to their acceptance thresholds. We present analytical arguments that allow an understanding of our results and give insights on the manner in which local effects in evolution may lead to such non-rational or apparently maladaptive behaviors.  相似文献   

13.
Step size in evolution is rapidly becoming a major subject of interest to biologists. Traditionally, small changes alone were seen as significant in evolution, and any large differences between an ancestor and its descendant could be explained entirely by the accumulation of many small steps. Whether the evolution of major adaptations is mainly a matter of amassing such small increments of change, or if a significant proportion occurs through the inclusion of one or more large steps, is vital to the understanding of how evolution works. This paper begins by examining four “classic” examples of animals—flatfishes, turtles, bolyerine snakes, and gastropod molluscs—each of which has seemed difficult to interpret as resulting from a continuous series of tiny increments. Recently, however, arguments have appeared to contradict those views, and to propose instead that each of these animal groups arose through continuous adaptive modifications. While some of these arguments are more plausible than others, the view of the present author is that in none of them is there convincing evidence to conclude that the groups arose solely through gradual changes. More specifically, there is no basis to reject an evolutionary origin of the major traits in each group that included at least one principal inovation, occurring in a large, discontinuous step, preceded and followed by relatively small, more gradual changes. The broader question of how discontinuous evolution may occur is addressed through several means. These include considerations of epigenetic (sensu Waddington) development, comparative embryology, population genetics, and other approaches. Overall the phenomenon of adaptive accommodation is seen as of major importance, and its implications for ameliorating possible deleterious attributes of novel phenotypes are discussed. In the course of these analyses the doctrine that all adaptive evolution is driven by external environmental change is reviewed. It is suggested that while small adaptive changes are often closely related to shifts in specific environmental facets, the modifications associated with more major adaptations may be less so.  相似文献   

14.
The evolution of secondary metabolism - a unifying model   总被引:1,自引:0,他引:1  
Why do microbes make secondary products? That question has been the subject of intense debate for many decades. There are two extreme opinions. Some argue that most secondary metabolites play no role in increasing the fitness of an organism. The opposite view, now widely held, is that every secondary metabolite is made because it possesses (or did possess at some stage in evolution) a biological activity that endows the producer with increased fitness. These opposing views can be reconciled by recognizing that, because of the principles governing molecular interactions, potent biological activity is a rare property for any molecule to possess. Consequently, in order for an organism to evolve the rare potent, biologically active molecule, a great many chemical structures have to be generated, most of which will possess no useful biological activity. Thus, the two sides of the debate about the role and evolution of secondary metabolism can be accommodated within the view that the possession of secondary metabolism can enhance fitness, but that many products of secondary metabolism will not enhance the fitness of the producer. It is proposed that secondary metabolism will have evolved such that traits that optimize the production and retention of chemical diversity at minimum cost will have been selected. Evidence exists for some of these predicted traits. Opportunities now exist to exploit these unique properties of secondary metabolism to enhance secondary product diversity and to devise new strategies for biotransformation and bioremediation.  相似文献   

15.
Eukaryotic sex leads to an alternation of haploid and diploid nuclear phases. Because all multicellular animals are diploid, diploidy is often considered a 'biological success' and many arguments have been advanced to explain the evolution of a prolonged diploid phase. Nevertheless, among eukaryotes three basic situations are encountered, where the vegetative individuals are diploid or haploid or both. These three basic life cycles are widely distributed among kingdoms and in some taxa the occurrence of different life cycles within the same species has been reported. This article briefly summarizes the different hypotheses on the evolution of reproductive life cycles and underlines how possibilities of variation for this trait may open new perspectives for research.  相似文献   

16.
Harris J 《Bioethics》1994,8(1):74-83
This paper restates some of the principal arguments against an automatic preference for the young as advocated by Kappel and Sandøe, arguments many of which have been extant for over a decade but which Kappel and Sandøe largely ignore. It then goes on to demonstrate that Kappel and Sandøe's "indifference test" fails to do the work required of it because it can be met by unacceptable conceptions of justice. The paper develops a number of new arguments against what I have called "ageist" preferences for the young or for those with long life expectancy. Finally I show that Kappel and Sandøe must believe that murdering older people is less morally wrong than murdering the young and that people relying on arguments such as theirs will have to accept the moral respectability of killing the innocent in order to maximise units of lifetime.  相似文献   

17.
Coughlan MJ 《Bioethics》1989,3(4):333-341
Coughlan reviews Norman M. Ford's When Did I Begin? Conception of the Human Individual in History, Philosophy and Science (Cambridge University Press; 1988). Ford, master of a Catholic theological college, has written a critique of the view that the life of the human person begins at the fertilization of the ovum. He believes that "when does a human being begin?" is an ontological question, and that attainment of personhood is a fact which calls for appropriate moral and legal attitudes, rather than a product of moral or legal attitudes or conventions. Ford bases his arguments on a detailed analysis of both the biological facts and the significance of early human embryology. Coughlan, while taking issue with some of Ford's reasoning, praises the book for its spirit of honesty, its well-argued transitions, and its instructiveness in human embryology. Ford's response to Coughlan follows the review.  相似文献   

18.
It is widely believed that the unique primary structure of a given protein is quite necessary for its folding into a certain three-dimensional structure as well as for its functioning and is a result of a directed selection in the course of biological evolution. The present paper provides arguments in favour of an alternative point of view according to which typical three-dimensional structures of globular proteins are characteristic even for random sequences of amino acid residues. Therefore it may be possible that primary structures of proteins are mainly examples of random amino acid sequences slightly edited in the course of biological evolution to impart them some additional (functional) meaning.  相似文献   

19.
Biological clock data from protein sequences indicate times for the divergence of humans and African apes that are only 2–3 million years before the present and hence inconsistent with the generally accepted view ofAustralopithecus on the evolutionary line toHomo. This inconsistency has been reconciled for most investigators by postulating a slowing of the biological clock among higher primates. However, there is no independent evidence for such a slowing, and for a number of reasons a specific slowing is unlikely. Therefore, an alternative paradigm is considered here based on the hypothesis that the molecular clock data are correct. The main consequence of this hypothesis is the placement ofA. afarensis in a position ancestral to African apes. An argument in support of this alternative paradigm is formulated concerning the evolution of knuckle-walking in African apes from ancestors whose bipedalism was already well developed. Published data are cited, particularly concerning the structure of the wrist, which accommodate poorly the evolution of African apes from palmigrad-walking or brachiating ancestors resemblingProconsul africanus orPongo. These arguments suggest that an alternative paradigm of hominoid evolution placingA. afarensis ancestral toHomo, Gorilla, andPan warrants further consideration.  相似文献   

20.
Examination of literature shows that a number of authors regard outbreeding and heterozygosity as the prevalent factors associated with long-term successful evolution in the angiosperms. A number of plant evolutionists, however, have doubted the truth of such an assumption. Everincreasing reports of the existence of arboreal angiospermous apomixis in tropical forests of the Neotropics and the Far East undermined a thinking which, recently, has rested on optimality. Finding apomixis in trees surprised authors, who held biased opinions about the determinism of outbreeding as the major guiding factor in the evolutionary history of the angiosperms. The thinking that apomixis may turn out to be a regular mating system of the flowering plants met with the approval of some authors, who wondered about the true penetration of the phenomenon among the higher plants. The fact that one-third of all known flowering plants are autogamous has cast further doubt on the deterministic infallibility of outbreeding and successful long-term evolution. Despite claims that the breeding system is directly involved with fitness, while determining the course of optimized evolution, there is comparatively little hard evidence to substantiate a hypothesis which, in the last analysis, has rested principally on common sense. Rather, if continuing field research happens to unveil new cases of woody angiospermous apomixis, a prediction is advanced that the next two biomes to show regular incidence of the phenomenon are Africa’s paleotropical savannas and humid forests. If evolution is partly or wholly dependent on the breeding system to proceed, current knowledge supports views that further enhancement of organic diversification vis-à-vis selection and adaptednesss rests on three major tested mating systems: outbreeding, inbreeding and apomixis.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号