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ABSTRACT

Discussions on the welfare of nonhuman animals in zoos tend to focus on incremental improvements without addressing the underlying problem of captivity. But alterations to the conditions of zoo captivity are irrelevant for animals. Real zoo reform will involve working to completely change the landscape. We offer six necessary reforms to bring zoos into a more ethical future: (1) Shut down bad zoos, now; (2) stop exhibiting animals who cannot and never will do well in captivity; (3) stop killing healthy animals; (4) stop captive breeding; (5) stop moving animals around from one zoo to another; and (6) use the science of animal cognition and emotion on behalf of animals.  相似文献   

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School science practical activities have been criticised for exposing learners to a series of phenomena disconnected from the conceptual frameworks needed to understand them. Such activities are successful in the ‘domain of observables’ but not the ‘domain of ideas’. Few resources exist for classroom teachers wishing to improve the effectiveness of practical activities in the domain of ideas. This report describes an action research project to develop a scaffold for biology practical lessons. This scaffold separates inquiry questions and the techniques needed to address them, and thus combines two approaches to scaffolding in a single tool (‘problematising’ and ‘reducing the degrees of freedom’). Analysis of the speech of 16–17 year olds in the study class (n = 23) was used to assess their engagement in the domain of ideas. Following the scaffold’s introduction, the learners were found to speak more about relevant ideas and concepts during practical activities. When the scaffold was partially faded, the learners continued to demonstrate engagement with the domain of ideas. The approach reported here would seem to have much potential for supporting learning from ‘minds-on’ biology practical work in a variety of contexts.  相似文献   

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Many topics in the secondary science classroom can be difficult to introduce to students in a manner that fully engages them, especially when presented using traditional teaching methods. However, with a little innovation and an emphasis on inquiry, even dry subjects can be presented in an appealing way. The authors developed an inquiry-based exercise that teaches students about flower anatomy and dissection. During this exercise, students investigate the morphology of simple and composite flowers using digital microscopes. Dissection of a simple flower results in a count of floral parts that is used to construct a floral formula. Students use appearance of structures to suggest function of sepals, petals, anthers, pistils, and components. Investigation of composite and bilabiate flowers introduces concepts of inflorescence and symmetry and asymmetry. Following self-guided inquiry by the students, the teacher uses a digital microscope, computer, and LCD projector to lead discussion of what was observed and to help assimilate important concepts.  相似文献   

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The biological species concept deals both with the meaning of the sexual species as a harmonious gene pool and with its protection against deleterious outbreeding (effected by isolating mechanisms). According to the Darwin-Muller-Mayr theory isolating mechanisms are acquired by incipient species during alloparty. Isolating mechanisms are not the result of ad hoc selection, but of a change of function of properties acquired during the preceding isolation of the incipient species. The role of behavioral properties (recognition) among the isolating mechanisms has long been recognized and described by naturalists but was rejected as basis of a species definition for a number of valid reasons.  相似文献   

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NAD+ and NADP+, chemically similar and with almost identical standard oxidation–reduction potentials, nevertheless have distinct roles, NAD+ serving catabolism and ATP generation whereas NADPH is the biosynthetic reductant. Separating these roles requires strict specificity for one or the other coenzyme for most dehydrogenases. In many organisms this holds also for glutamate dehydrogenases (GDH), NAD+-dependent for glutamate oxidation, NADP+-dependent for fixing ammonia. In higher animals, however, GDH has dual specificity. It has been suggested that GDH in mitochondria reacts only with NADP(H), the NAD+ reaction being an in vitro artefact. However, contrary evidence suggests mitochondrial GDH not only reacts with NAD+ but maintains equilibrium using the same pool as accessed by β-hydroxybutyrate dehydrogenase. Another complication is the presence of an energy-linked dehydrogenase driving NADP+ reduction by NADH, maintaining the coenzyme pools at different oxidation–reduction potentials. Its coexistence with GDH makes possible a futile cycle, control of which is not yet properly explained. Structural studies show NAD+-dependent, NADP+-dependent and dual-specificity GDHs are closely related and a few site-directed mutations can reverse specificity. Specificity for NAD+ or for NADP+ has probably emerged repeatedly during evolution, using different structural solutions on different occasions. In various GDHs the P7 position in the coenzyme-binding domain plays a key role. However, whereas in other dehydrogenases an acidic P7 residue usually hydrogen bonds to the 2′- and 3′-hydroxyls, dictating NAD+ specificity, among GDHs, depending on detailed conformation of surrounding residues, an acidic P7 may permit binding of NAD+ only, NADP+ only, or in higher animals both.  相似文献   

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Regional fishery organizations are increasingly being viewed as "vehicles of good governance" created to secure the sustainable development of international fisheries. These political expectations have not been followed by analytical refinement of how to explain and understand their formation, roles, objectives, institutional setups, or efficiency. This article provides a conceptual discussion of regional fishery organizations and introduces an organizational typology as a basis for their study. Thus, an analytical distinction is made between regional fisheries management organizations, regional coordination and development organizations and scientific research organizations. This typology and the evolution of the Law of the Sea, from an open access to the exclusive economic zone regime, are used to analyze the institutional arrangements of regional fishery organizations.  相似文献   

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《Anthrozo?s》2013,26(4):441-443
ABSTRACT

There is growing evidence that pet ownership and human–animal interaction (HAI) have benefits for human physical and psychological well-being. However, there may be pre-existing characteristics related to patterns of pet ownership and interactions with pets that could potentially bias results of research on HAI. The present study uses a behavioral genetic design to estimate the degree to which genetic and environmental factors contribute to individual differences in frequency of play with pets among adult men. Participants were from the ongoing longitudinal Vietnam Era Twin Study of Aging (VETSA), a population-based sample of 1,237 monozygotic (MZ) and dizygotic (DZ) twins aged 51–60 years. Results demonstrate that MZ twins have higher correlations than DZ twins on frequency of pet play, suggesting that genetic factors play a role in individual differences in interactions with pets. Structural equation modeling revealed that, according to the best model, genetic factors accounted for as much as 37% of the variance in pet play, although the majority of variance (63–71%) was due to environmental factors that are unique to each twin. Shared environmental factors, which would include childhood exposure to pets, overall accounted for <10% of the variance in adult frequency of pet play, and were not statistically significant. These results suggest that the effects of childhood exposure to pets on pet ownership and interaction patterns in adulthood may be mediated primarily by genetically-influenced characteristics.  相似文献   

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