The Two Coexisting Ecological Paradigms

We analyse theories and research approaches in ecology and find that they fall into two internally homogeneous groups of linked ideas, each comprising a unique set of premises. The two sets of interpretive statements are thus mutually exclusive; they constitute alternative theoretical developments in ecology and should not be seen as complementary. They can, therefore, be considered two paradigms (Kuhn, 1962). Our interpretation is supported by the minimal overlap, if any, in the premises and research directions of the two approaches. We label the dominant group of ideas the demographic paradigm and the less developed one the autecological paradigm. The internal logic of the demographic paradigm of ecology is strongly developed and consistent. Its premises and logic extend into current models of population genetics, biogeography, palaeontology, evolutionary theory and conservation biology. Nevertheless, many phenomena contradict the premises of the demographic paradigm; these contradictions cannot be accommodated within its theoretical framework without major disruptions in logic ensuing. Such phenomena can, in contrast, be understood in terms of the autecological paradigm. Because the status and strengths of the autecological paradigm are generally unrecognised and because autecology is frequently misrepresented in the literature, we redefine its premises and clarify its structure and aims as an aid to its future development.     

General Introduction to the Symposium on Evolutionary Developmental Biology: Paradigms, Problems, and Prospects

This symposium undertakes to examine some historical backgroundrelevant to the renaissance in biological studies linking evolutionand development, to review the current status of research inthis rapidly changing area (especially the problem of forginglinks between disciplines that have gone in divergent directions),to address the benefits and difficulties that arise from molecularstudies of the relationship between evolution and development,and to help set the research agenda in evolutionary developmentalbiology in the next few years. Rather than introducing the individualcontributions that follow, this paper aims to set some historicalbackground for the topics they cover. I argue that old questionsabout the relationship of development to evolution, raised bysuch figures as William Bateson and Richard Goldschmidt, remainrelevant to contemporary work, though they require major reformulationin light of subsequent developments. Many older questions, longset aside as intractable, remain open. Recently developed techniquesmay enable us to answer some of them. Accordingly, I suggest,it is worth reviewing the work of several historical figuresin setting current research agendas.     

The Structure of the Two Ecological Paradigms

Ecological theory is built upon assumptions about the fundamental nature of organism-environment interactions. We argue that two mutually exclusive sets of such assumptions are available and that they have given rise to alternative approaches to studying ecology. The fundamentally different premises of these approaches render them irreconcilable with one another. In this paper, we present the first logical formalisation of these two paradigms.The more widely-accepted approach - which we label the demographic paradigm - includes both population ecology and community ecology (synecology). Demographic ecology assumes that the environment is relatively stable and that biotic processes, governed predominantly by resource availability, are the most important of ecological and evolutionary influences. Moreover, ecological processes are assumed to translate into directional selection pressures that drive significant evolutionary change on a local scale through the process of optimisation.Serious deficiencies in aspects of the demographic approach have been identified over the past few decades by various ecologists, including Gleason, Andrewartha and Birch, White, Den Boer, Strong, Simberloff, and others. Short-term evolutionary optimisation has also been seriously questioned.The development of the alternative approach (autecology) has been subverted by the prominence of demographic ecology. Moreover, it has not been recognised that autecology is underpinned by robust principles and that they are independent of the underlying demographic principles. Components of the autecological approach have been developed to some extent, but they have not been integrated with ancillary fields of study. We therefore articulate the assumptions from which autecology is derived, and use this as a basis for integrating the various spheres of autecological research.We add to the ongoing development of autecology by linking autecological understanding, in so far as it is developed, with the evolutionary justification for species' characteristics being stable in an environment that is continuously dynamic in space and time. The ecology of organisms is essentially an ongoing matching of their species-specific characteristics to the prevailing environmental factors and dynamics. We thus provide a consistent logic through the following subject areas; climate and climate change, spatial and temporal environmental heterogeneity and dynamic theory, physiology, behaviour, migration, and evolution. We demonstrate why adaptation cannot be an ongoing process, but takes place only when organisms are prevented, by incidental influences, from matching the overall dynamics of the environment.     

科技考古研究范式之思考

范式自20世纪60年代创立以来,已普遍使用于多个科学研究领域,并于七八十年代引入至考古学。目前,国内外学界对考古学的研究范式有不少讨论,但对科技考古的研究范式的认知仍属空白。本文在简要介绍科学研究范式和考古学研究范式的基础上,首次提出了科技考古研究的3种范式,即科技范式、考古范式、科技考古融合范式,详细阐述了3种研究范式的理论、方法、实践等。此外,本文还指出：科技范式是推动科技考古研究发展的“发动机”,考古范式是掌控科技考古研究方向的“方向盘”,而科技考古融合范式则是协调科技考古各研究领域的“中控台”,真正让科技与考古融为一体。最后,笔者还对在科技考古研究范式下如何构建研究人员的知识体系提出了一些看法。     

Paradigms of plasmid organization

Plasmids are extrachromosomal elements built from a selection of generally quite well understood survival and propagation functions, including replication, partitioning, multimer resolution, post-segregational killing and conjugative transfer. Evolution has favoured clustering of these modules to form plasmid cores or backbones. Co-regulation of these core genes can also provide advantages that favour retention of the backbone organization. Tumour-inducing and symbiosis-determining plasmids appear to co-regulate replication and transfer in response to cell density, both being stimulated at high density. Broad-host-range plasmids of the IncP-1 group, on the other hand, have autogenous control circuits, which allow a burst of expression during establishment in a new host, but a minimum of expression during maintenance. The lessons that plasmids have for clustering and co-regulation may explain the logic and organization of many small bacterial genomes currently being investigated.     

Paradigms of expected failure

This study explores the outsourcing and offshoring of clinical trials and how they interconnect with the dynamics of drug development and regulation in the United States. I focus on the activities of United States-based contract research organizations, which make up a specialized global clinical trials industry focusing on the recruitment of human subjects and investigators. Tracking this industry’s activities in eastern Europe and Latin America, two clinical trial market ‘growth regions,’ I address the strategies of evidence-making that inform clinical trial offshoring. I also show how aspects of the clinical trial model—in which failures to predict safety outcomes or a paradigm of expected failure—are being exported along with the offshored trial. The clinical trials industry is a crucial, highly mobile, and profitable arm of the global pharmaceutical industry. Where state agencies furnish limited or no health care, drug developers claim that trial expansion and experiments have become social goods in themselves. But questions remain: How is drug value and research integrity maintained? And how do the results of clinical trials strengthen or undermine the delivery of affordable and effective interventions? As this essay shows, clinical trials are not only hypothesis-testing instruments; they are operative environments redistributing resources and occasioning tense medical and social fields. In highlighting the inefficiencies and uncertainties of global drug development, this study points to problems in the operational model of drug development and in systems of human protection. It also considers new forms of accountability at the nexus of private sector science and public health.