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The broader context for the formal darwinism project established by two of the commentators, in terms of reconciling the Modern Synthesis with Darwinian arguments over design and in terms of links to other types of selection and design, is discussed and welcomed. Some overselling of the project is admitted, in particular of whether it claims to consider all organic design. One important fundamental question raised in two commentaries is flagged but not answered of whether design is rightly represented by an optimisation program, and another from one commentary of whether the coreplicon dissolves in the face of multi-generational imprinting. Calls for the project to be extended to design at levels above and below the individual are considered sympathetically, but judged impractical at the high level of abstraction of the project. All claims of substantive technical error are emphatically rejected. Close technical readings are welcomed that, among other things, represent the project as 'axiomatizing fitness'. The prospects for the project are set out in the light of this highly varied set of commentaries.  相似文献   

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We consider the question: under what circumstances can the concept of adaptation be applied to groups, rather than individuals? Gardner and Grafen (2009, J. Evol. Biol. 22 : 659–671) develop a novel approach to this question, building on Grafen's ‘formal Darwinism’ project, which defines adaptation in terms of links between evolutionary dynamics and optimization. They conclude that only clonal groups, and to a lesser extent groups in which reproductive competition is repressed, can be considered as adaptive units. We re‐examine the conditions under which the selection–optimization links hold at the group level. We focus on an important distinction between two ways of understanding the links, which have different implications regarding group adaptationism. We show how the formal Darwinism approach can be reconciled with G.C. Williams’ famous analysis of group adaptation, and we consider the relationships between group adaptation, the Price equation approach to multi‐level selection, and the alternative approach based on contextual analysis.  相似文献   

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The formal Darwinism project: a mid-term report   总被引:1,自引:0,他引:1  
For 8 years I have been pursuing in print an ambitious and at times highly technical programme of work, the 'Formal Darwinism Project', whose essence is to underpin and formalize the fitness optimization ideas used by behavioural ecologists, using a new kind of argument linking the mathematics of motion and the mathematics of optimization. The value of the project is to give stronger support to current practices, and at the same time sharpening theoretical ideas and suggesting principled resolutions of some untidy areas, for example, how to define fitness. The aim is also to unify existing free-standing theoretical structures, such as inclusive fitness theory, Evolutionary Stable Strategy (ESS) theory and bet-hedging theory. The 40-year-old misunderstanding over the meaning of fitness optimization between mathematicians and biologists is explained. Most of the elements required for a general theory have now been implemented, but not together in the same framework, and 'general time' remains to be developed and integrated with the other elements to produce a final unified theory of neo-Darwinian natural selection.  相似文献   

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The development of evolutionary theory requires the resolution of the problem of relationships between random and regular processes in historical development of biological systems. According to the theory of natural selection, ecological factors play a leading role in evolution. Variations are nondirectional, unpredictable, and provide chaotic diversity of variants, only some of which are potentially useful. However, based on random processes, new variants that are useful for organisms and remain adaptive significance in various ecological situations are infrequent. At the same time, morphology demonstrates certain evolutionary patterns. The morphological approach takes into account the role in evolution of structural features of organism and social systems and evolutionary significance of “constructive technologies,” which distinguish morphological interpretation of evolutionary processes. The constructive and evolutionary patterns revealed in biological systems provide the basis for morphological interpretation of the principle of natural selection: both natural and artificial selection is interaction between social systems (populations, ecosystems, biogeocoenoses) and organisms composing them.  相似文献   

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The theory of nomogenesis put forward by L. S. Berg in 1922 is discussed. It is shown that side by side with some erroneous anti-darwinian ideas the theory contains a series of important suggestions which anticipate the further development of the synthetic theory of evolution. Berg has foreseen the development of molecular biology. Thus he was the fore-teller of our branch of science. The theory of nomogenesis emphasized the limitations of natural selection which determine the directionality of evolution. Berg treated the speciation as a kind of phase transition. Even the most conscientious critics of Berg have misrepresented the real sense of his works. It is totally groundless to treat nomogenesis as an idealistic of Lamarkian theory. Berg was superior to his critics. However the enthusiasm about nomogenesis in our time shows the inability to separate "the grains from weeds".  相似文献   

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Understanding good design requires addressing the question of what units undergo natural selection, thereby becoming adapted. There is, therefore, a natural connection between the formal Darwinism project (which aims to connect population genetics with the evolution of design and fitness maximization) and levels of selection issues. We argue that the formal Darwinism project offers contradictory and confusing lines of thinking concerning level(s) of selection. The project favors multicellular organisms over both the lower (cell) and higher (social group) levels as the level of adaptation. Grafen offers four reasons for giving such special status to multicellular organisms: (1) they lack appreciable within-organism cell selection, (2) they have multiple features that appear contrived for the same purpose, (3) they possess a set of phenotypes, and (4) they leave offspring according to their phenotypes. We discuss why these rationales are not compelling and suggest that a more even-handed approach, in which multicellular organisms are not assumed to have special status, would be desirable for a project that aims to make progress on the foundations of evolutionary theory.  相似文献   

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The molecular darwinian approach to the emergence of life treats the competition between RNA sequences for nucleotide resources as the primordial selective process in prebiotic evolution, which prescribes possible pathways for the subsequent elaboration of organizational relationships. Since success in this competition is determined by the "phenotypic" properties of RNA strands in the absence of organizational context, the genesis of biotic organization is dependent upon the establishment of co-operative, hypercyclic interactions between competing RNA sequences. The thesis of this paper is that hypercycle theory is based on unwarranted assumptions about the conditions of prebiotic evolution, and that the implications of these assumptions run counter to both empirical evidence and to the rational by which natural selection operates in evolution generally. An organismic alternative to hypercycle theory is suggested, based on the catalytic microsphere and the thermodynamics of selection.  相似文献   

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This paper pursues the ‘formal darwinism’ project of Grafen, whose aim is to construct formal links between dynamics of gene frequencies and optimization programmes, in very abstract settings with general implications for biologically relevant situations. A major outcome is the definition, within wide assumptions, of the ubiquitous but problematic concept of ‘fitness’. This paper is the first to present the project for mathematicians. Within the framework of overlapping generations in discrete time and no social interactions, the current model shows links between fitness maximization and gene frequency change in a class-structured population, with individual-level uncertainty but no uncertainty in the class projection operator, where individuals are permitted to observe and condition their behaviour on arbitrary parts of the uncertainty. The results hold with arbitrary numbers of loci and alleles, arbitrary dominance and epistasis, and make no assumptions about linkage, linkage disequilibrium or mating system. An explicit derivation is given of Fisher’s Fundamental Theorem of Natural Selection in its full generality.  相似文献   

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Leon Bennun  Lincoln Fishpool 《Ostrich》2013,84(1-2):150-153
Bennun, L. & Fishpool, L. 2000. The Important Bird Areas Programme in Africa: an outline. Ostrich 71 (1 & 2): 150–153.

BirdLife International works to conserve the world's birds at the levels of species, sites and habitats. The Important Bird Areas (IBA) programme is a process of setting site-based priorities for birds based on information about species' distribution and numbers. The African IBA programme started in 1993, building on similar successful programmes in Europe and the Middle East. Important Bird Areas are selected according to internationally agreed criteria based upon the presence of globally threatened species, species of restricted range, biome-restricted species assemblages and concentrations of numbers.

In Africa, a continental directory of sites is scheduled for publication in 2000, and work is underway to identify and document IBAs across the continent and its associated islands. In 18 countries so far, the process of compiling information is being combined at a national level with strengthening the capacity for research and action, and building effective structures (especially NGO-Government linkages) for advocacy and action. The resulting inventories can be used in numerous ways to prioritise, inform and stimulate conservation action at local and national levels.  相似文献   

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A brief summary of the principal notions of the quantum-mechanical theory of the charge transfer reactions has been presented. In the framework of this theory, the mechanism of the proton transfer consists in the classical medium reorganization that equalizes the proton energy levels in the initial and final states, and a consequent proton transfer via a quantum-mechanical underbarrier transition. On the basis of this mechanism, factors influencing the proton transfer probability, and hence kinetic isotope effect, have been discussed; among them are the optimum tunneling distance, the involvement of the excited vibrational states, etc. Semi-classical and quantum-mechanical treatments of the Swain-Schaad relations have been compared. Some applications to enzymatic proton-transfer reactions have been described.  相似文献   

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