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1.
Conceptions of adaptation have varied in the history of genetic Darwinism depending on whether what is taken to be focal is the process of adaptation, adapted states of populations, or discrete adaptations in individual organisms. I argue that Theodosius Dobzhansky's view of adaptation as a dynamical process contrasts with so-called "adaptationist" views of natural selection figured as "design-without-a-designer" of relatively discrete, enumerable adaptations. Correlated with these respectively process and product oriented approaches to adaptive natural selection are divergent pictures of organisms themselves as developmental wholes or as "bundles" of adaptations. While even process versions of genetical Darwinism are insufficiently sensitive to the fact much of the variation on which adaptive selection works consists of changes in the timing, rate, or location of ontogenetic events, I argue that articulations of the Modern Synthesis influenced by Dobzhansky are more easily reconciled with the recent shift to evolutionary developmentalism than are versions that make discrete adaptations central.  相似文献   

2.
The notion that natural selection is a process of fitness maximization gets a bad press in population genetics, yet in other areas of biology the view that organisms behave as if attempting to maximize their fitness remains widespread. Here I critically appraise the prospects for reconciliation. I first distinguish four varieties of fitness maximization. I then examine two recent developments that may appear to vindicate at least one of these varieties. The first is the ‘new’ interpretation of Fisher's fundamental theorem of natural selection, on which the theorem is exactly true for any evolving population that satisfies some minimal assumptions. The second is the Formal Darwinism project, which forges links between gene frequency change and optimal strategy choice. In both cases, I argue that the results fail to establish a biologically significant maximization principle. I conclude that it may be a mistake to look for universal maximization principles justified by theory alone. A more promising approach may be to find maximization principles that apply conditionally and to show that the conditions were satisfied in the evolution of particular traits.  相似文献   

3.
The Formal Darwinism Project is an attempt to use mathematical theory to prove the claim that fitness maximization is the outcome of evolution in nature. Grafen’s (2014, p. 12) conclusion from this project is that “….there is a very general expectation of something close to fitness maximisation, which will convert into fitness-maximisation unless there are particular kinds of circumstances—and further, that fitness is the same quantity for all genetic architectures.” Grafen’s claim appears to mean to him that natural populations are expected to contain individuals whose traits are optimal, i.e., any given trait outperforms all reasonable alternatives. I describe why Grafen’s attempt can never provide a meaningful expectation as to the ubiquity of optimal traits in nature. This is so because it is based upon a misconception of the relationship between theory and empirical analysis. Even if one could use theory in the way Grafen proposes, I describe how his theory is causally incomplete. Finally, I describe how Grafen’s conceptual framework is ambiguous. The Formal Darwinism Project has been inspired by “On The Origin of Species” by Darwin. The great lesson of this book was Darwin’s demonstration of the necessary dialog between theory and data, with each influencing and being influenced by the other. Grafen’s Formal Darwinism Project, an attempt to create understanding of nature by removing data from this dialog, reflects a failure to understand Darwin’s great lesson.  相似文献   

4.
This paper uses the framework of Formal Darwinism (FD) to evaluate organism-centric critiques of the Modern Synthesis (MS). The first section argues that the FD project reconciles two kinds of selective explanations in biology. Thus it is not correct to say that the MS neglects organisms—instead, it explains organisms’ design, as argued in the second section. In the third section I employ a concept of the organism derived from Kant that has two aspects: the parts presupposing the whole, and the productivity of the parts in relation to the whole. The first aspect corresponds to the “design” that FD explains, whereas the second aspect is something about which the MS is largely silent.  相似文献   

5.
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   

6.
One key aim of Grafen’s Formal Darwinism project is to formalize ‘modern biology’s understanding and updating of Darwin’s central argument’. In this commentary, I consider whether Grafen has succeeded in this aim.  相似文献   

7.
This is the first of a two-part essay on the history of debates concerning the creativity of natural selection, from Darwin through the evolutionary synthesis and up to the present. Here I focus on the mid-late nineteenth century to the early twentieth, with special emphasis on early Darwinism and its critics, the self-styled “mutationists.” The second part focuses on the evolutionary synthesis and some of its critics, especially the “neutralists” and “neo-mutationists.” Like Stephen Gould, I consider the creativity of natural selection to be a key component of what has traditionally counted as “Darwinism.” I argue that the creativity of natural selection is best understood in terms of (1) selection initiating evolutionary change, and (2) selection being responsible for the presence of the variation it acts upon, for example by directing the course of variation. I consider the respects in which both of these claims sound non-Darwinian, even though they have long been understood by supporters and critics alike to be virtually constitutive of Darwinism.  相似文献   

8.
There are two extant theories of evolution, each of which deserves the honourific "neo-Darwinism": Modern Synthesis Replicator theory and a theory I shall call Developmental Darwinism. The principal difference concerns the canonical unit of biological organization. Modern Synthesis replicator theory explains the process of evolution by appeal to the activities of genes or replicators. Developmental Darwinism explains the process of evolution by appeal to the capacities of organisms. In particular, it is the plasticity of organisms, manifested most distinctly during development, that causes adaptive evolution. Despite the fact that each, in its own way, traces its origin to the theory outlined by Darwin, they are radically different. The objectives of this essay are twofold: to underscore the differences between these theories, and to argue that Developmental Darwinism, though nascent, is a viable alternative to Modern Synthesis replicator theory.  相似文献   

9.
The problem of adaptation is to explain the apparent design of organisms. Darwin solved this problem with the theory of natural selection. However, population geneticists, whose responsibility it is to formalize evolutionary theory, have long neglected the link between natural selection and organismal design. Here, I review the major historical developments in theory of organismal adaptation, clarifying what adaptation is and what it is not, and I point out future avenues for research.  相似文献   

10.
I investigate the role of palaeontology within Darwin's works through an analysis of the two chapters of The Origin of Species most especially devoted to this science. Palaeontology may occupy several places within the structure of the argumentative logic of Darwinism, but these places have remained to some extent ancillary. Indeed, palaeontology could well document evolutionary patterns, showing the actual occurrence of evolution as a general “historical fact”, but it was poorly adapted to demonstrate the main point of Darwinism: the actual evolutionary process: natural selection acting among individuals. I also show, in agreement with Gould, that Darwin had great confidence in the ultimate ability of palaeontology to support his theory, and that in interpreting palaeontological evidence, he expressed a vision of natural selection much wider and more eclectic than that which has generally been ascribed to him.  相似文献   

11.
Evolutionary adaptation has been suggested as the hallmark of life that best accounts for life’s creativity. However, current evolutionary approaches still fail to give an adequate account of it, even if they are able to explain both the origin of novelties and the proliferation of certain traits in a population. Although modern-synthesis Darwinism is today usually appraised as too narrow a position to cope with all the complexities of developmental and structural biology—not to say biosemiotic phenomena—, Darwinism need not be if we separate metaphor from reality in natural selection in order to show the axiological complexity of this concept. This can shed light on the relationship between biosemiotics and biological evolution.  相似文献   

12.
Following Wallace's suggestion, Darwin framed his theory using Spencer's expression "survival of the fittest". Since then, fitness occupies a significant place in the conventional understanding of Darwinism, even though the explicit meaning of the term 'fitness' is rarely stated. In this paper I examine some of the different roles that fitness has played in the development of the theory. Whereas the meaning of fitness was originally understood in ecological terms, it took a statistical turn in terms of reproductive success throughout the 20th Century. This has lead to the ever-increasing importance of sexually reproducing organisms and the populations they compose in evolutionary explanations. I will argue that, moving forward, evolutionary theory should look back at its ecological roots in order to be more inclusive in the type of systems it examines. Many biological systems (e.g. clonal species, colonial species, multi-species communities) can only be satisfactorily accounted for by offering a non-reproductive account of fitness. This argument will be made by examining biological systems with very small or transient population structures. I argue this has significant consequences for how we define Darwinism, increasing the significance of survival (or persistence) over that of reproduction.  相似文献   

13.
Evolutionary theory seems to lend itself to all sorts of misunderstanding. In this paper I strive to decrease such confusions, for example, between Darwinism and Darwinians, propositions and people, organisms and individuals, species as individuals versus species as classes, homologies and homoplasies, and finally essences versus histories.  相似文献   

14.
In this paper I propose a new interpretation of the British evolutionary synthesis. The synthetic work of J. B. S. Haldane, R. A. Fisher and J. S. Huxley was characterized by both an integration of Mendelism and Darwinism and the unification of different biological subdisciplines within a coherent framework. But it must also be seen as a bold and synthetic Darwinian program in which the biosciences served as a utopian blueprint for the progress of civilization. Describing the futuristic visions of these three scientists in their synthetic heydays, I show that, despite a number of important divergences, their biopolitical ideals could be biased toward a controlled and regimented utopian society. Their common ideals entailed a social order where liberal and democratic principles were partially or totally suspended in favor of bioscientific control and planning for the future. Finally, I will argue that the original redefinition of Darwinism that modern synthesizers proposed is a significant historical example of how Darwinism has been used and adapted in different contexts. The lesson I draw from this account is a venerable one: that, whenever we wish to define Darwinism, we need to recognize not only its scientific content and achievements but expose the other traditions and ideologies it may have supported.  相似文献   

15.
This article discusses some of the ways in which Darwinism has influenced a small minority of economists. It is argued that Darwinism involves a philosophical as well as a theoretical doctrine. Despite claims to the contrary, the uses of analogies to Darwinian natural selection theory are highly limited in economics. Exceptions include Thorstein Veblen, Richard Nelson, and Sidney Winter. At the philosophical level, one of the key features of Darwinism is its notion of detailed understanding in terms of chains of cause and effect. This issue is discussed in the context of the problem of causality in social theory. At least in Darwinian terms, the prevailing causal dualism--of intentional and mechanical causality--in the social sciences is found wanting. Once again, Veblen was the first economist to understand the implications for economics of Darwinism at this philosophical level. For Veblen, it was related to his notion of 'cumulative causation'. The article concludes with a discussion of the problems and potential of this Veblenian position.  相似文献   

16.
According to Ch. Darwin's evolutionary theory, evolutionary progress (interpreted as morpho-physiological progress or arogenesis in recent terminology) is one of logical results of natural selection. At the same time, natural selection does not hold any factors especially promoting evolutionary progress. Darwin emphasized that the pattern of evolutionary changes depends on organism nature more than on the pattern of environment changes. Arogenesis specificity is determined by organization of rigorous biological systems - integral organisms. Onward progressive development is determined by fundamental features of living organisms: metabolism and homeostasis. The concept of social Darwinism differs fundamentally from Darwin's ideas about the most important role of social instincts in progress of mankind. Competition and selection play secondary role in socio-cultural progress of human society.  相似文献   

17.
Mark Ravinet 《Molecular ecology》2018,27(13):2781-2789
The most successful study systems are built on a foundation of decades of research on the basic biology, ecology and life history of the organisms in question. Combined with new technologies, this can provide a formidable means to address important issues in evolutionary biology and molecular ecology. Littorinid marine snails are a good example of this, with a rich literature on their taxonomy, speciation, thermal tolerance and behavioural adaptations. In August 2017, an international meeting on Littorinid evolution was held at the Tjärnö Marine Research Laboratory in Western Sweden. In this meeting review, I provide a summary of some of the exciting work on parallel evolution, sexual selection and adaptation to environmental stress presented there. I argue that newly available genomic resources present an opportunity for integrating the traditionally divergent fields of speciation and environmental adaptation in Littorinid research.  相似文献   

18.
李启剑  李越 《生物学杂志》2010,27(2):55-57,12
适应性突变(adaptive mutation)和表观遗传学(epigenetics)的新进展为拉马克主张的"获得性遗传"提供了越来越多的证据,暗示它在生物进化中所起的作用可能远比我们之前想象的要大的多。这虽然与新达尔文主义相左,但却在一定程度上符合经典达尔文主义:作为"自然选择"的重要补充,"获得性遗传"至少应视作一个辅助的机制而纳入"达尔文框架"中。这种建立在多元论基础上的进化观正是达尔文留给后人最重要的遗产。  相似文献   

19.
Evolutionary ethics has a long history, dating all the way back to Charles Darwin. Almost immediately after the publication of the Origin, an immense interest arose in the moral implications of Darwinism and whether the truth of Darwinism would undermine traditional ethics. Though the biological thesis was certainly exciting, nobody suspected that the impact of the Origin would be confined to the scientific arena. As one historian wrote, 'whether or not ancient populations of armadillos were transformed into the species that currently inhabit the new world was certainly a topic about which zoologists could disagree. But it was in discussing the broader implications of the theory...that tempers flared and statements were made which could transform what otherwise would have been a quiet scholarly meeting into a social scandal' (Farber 1994, 22). Some resistance to the biological thesis of Darwinism sprung from the thought that it was incompatible with traditional morality and, since one of them had to go, many thought that Darwinism should be rejected. However, some people did realize that a secular ethics was possible so, even if Darwinism did undermine traditional religious beliefs, it need not have any effects on moral thought. Before I begin my discussion of evolutionary ethics from Darwin to Moore, I would like to make some more general remarks about its development. There are three key events during this history of evolutionary ethics. First, Charles Darwin published On the Origin of the Species (Darwin 1859). Since one did not have a fully developed theory of evolution until 1859, there exists little work on evolutionary ethics until then. Shortly thereafter, Herbert Spencer (1898) penned the first systematic theory of evolutionary ethics, which was promptly attacked by T.H. Huxley (Huxley 1894). Second, at about the turn of the century, moral philosophers entered the fray and attempted to demonstrate logical errors in Spencer's work; such errors were alluded to but never fully brought to the fore by Huxley. These philosophers were the well known moralists from Cambridge: Henry Sidgwick (Sidgwick 1902, 1907) and G.E. Moore (Moore 1903), though their ideas hearkened back to David Hume (Hume 1960). These criticisms were so strong that the industry of evolutionary ethics was largely abandoned (though with some exceptions) for many years. Third, E.O. Wilson, a Harvard entomologist, published Sociobiology: The New Synthesis in 1975 (Wilson E.O. 1975), which sparked renewed interest in evolutionary ethics and offered new directions of investigation. These events suggest the following stages for the history of evolutionary ethics: development, criticism and abandonment, revival. In this paper, I shall focus on the first two stages, since those are the ones on which the philosophical merits have already been largely decided. The revival stage is still in progress and we shall eventually find out whether it was a success.  相似文献   

20.
Shapiro claims that advances in molecular genetics have undermined Darwinism, leading him to advocate mutationism. However, this extreme view is bourne out of conceptual error. He has misunderstood the distinction between gradualism and saltationism, which do not concern the rate of genetic change, but rather the emergence of complex design. And he has misunderstood the relationship between the dynamics of natural selection and the agency of individual organisms: these are not competing hypotheses, but rather alternative conceptualizations of the same phenomenon.  相似文献   

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