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1.
Recently, biologist and philosophers have been much attracted by an evolutionary view of knowledge, so-called evolutionary epistemology. Developing this insight, the present paper argues that our cognitive abilities are the outcome of organic evolution, and that, conversely, evolution itself may be described as a cognition process. Furthermore, it is argued that the key to an adequate evolutionary epistemology lies in a system-theoretical approach to evolution which grows from, but goes beyond, Darwin's theory of natural selection.  相似文献   

2.
This article starts from the assumption that there are various innate contributions to our view of the world and explores the epistemological implications that follow from this. Specifically, it explores the idea that if certain components of our worldview have an evolutionary origin, this implies that these aspects accurately depict the world. The simple version of the argument for this conclusion is that if an aspect of mind is innate, it must be useful, and the most parsimonious explanation for its usefulness is that it accurately depicts the world. There are a number of important criticisms of this argument. These include the idea that evolutionary justifications are circular, that evolved mental content and principles are not necessarily accurate, and that, if the argument is taken seriously, it has some highly dubious consequences. These criticisms necessitate various qualifications to the initial argument. Nonetheless, it is argued that, in some cases, important conclusions can be drawn about the world from an analysis of evolved contributions to our view of the world. An evolutionary approach cannot provide an ultimate justification for any belief; however, in certain circumstances, it supports the conclusion that a given belief is a reasonable first approximation. To the extent that innate content and principles pertain to topics in metaphysics, they can be viewed as a naturalistic source of metaphysical knowledge.  相似文献   

3.
In The Expression of the Emotions, Charles Darwin documents evolutionary continuity between animals and humans, emphasizing the universality of expressions in man. Most of the book addresses human behavior, and its influence on the study of animal behavior has been weak. The issue of natural selection is remarkably absent from this book, which relies on the inheritance of acquired characters rather than on a genuine Darwinian logic. Yet Konrad Lorenz considered Darwin to be a forerunner of behavioral biology. The reason was to be found in The Descent of Man and chapter VIII of The Origin of Species, where Darwin provides an explanation of behavior through selection, stating that the same mechanisms explaining morphological changes also account for gradual improvements in instincts. He assessed the accuracy of his evolutionary theory by directly studying animal behavior, hence laying the foundations of behavioral research for the next century.  相似文献   

4.
We hypothesize a mechanism for reinforcing transitions between levels of selection, involving physiological homeostasis and amplification of variation in the physical environment. Groups experience a stronger selection pressure than individuals for homeostasis with respect to reproductively limiting variables, because their greater longevity exposes them more often to suboptimal physical conditions, and greater physical size means they encompass a larger fraction of any resource/nutrient gradient. Groups achieve homeostasis by differentiation into microcosms with specialist functions, e.g. cell types. Such differentiation is more limited in individuals due to their smaller size and shorter lifespan. Hence tolerance of fluctuation in certain physical variables is proposed to be weaker in individuals than in groups. We show that a trait providing increased tolerance (alpha) to fluctuation (V-V(opt)) in a limiting abiotic variable (V), at relative fitness cost (C), can increase from rarity if the condition alpha.mid R:V-V(opt)|>C is met. Groups also sequester larger absolute quantities of resource than individuals, and group death is less frequent, hence the population dynamics of groups cause resource/nutrient availability to fluctuate with greater amplitude than that of individuals. Increasing the amplitude of fluctuation in a reproductively limiting environmental variable is proposed as a mechanism by which a group can limit reproduction of parasitic "cheat" individuals. Enhancing physical fluctuation is frequency dependent, hence only an increase in tolerance to fluctuation can explain the group's increase from rarity. However, once groups reach intermediate frequencies, a positive feedback process can be initiated in which a differentiated group enhances physical fluctuation beyond the tolerance of any "cheat", and in so doing enhances the selection pressure it experiences for homeostasis. This may help explain the persistence of transitions in individuality, and the coincidence of some such transitions with periods of change and oscillation in global scale environmental variables.  相似文献   

5.
Joseph C. Polacco 《Planta》1979,146(2):155-160
Sodium arsenate is toxic to cultured soybean [Glycine max (L.) Merr.] cells, killing virtually 100% of the cells during a 24-h exposure at a 1–2 mM concentration. However, when growth is previously halted by nitrogen deprivation 50–100% of the cells survive arsenate treatment. Because of this growthdependent toxicity, arsenate has promise as a negative selection agent for cultured plant cells. Using arsenate (2 mM) I was able to select from among 2×107 cells a cell line with a growth requirement for an amino acid mixture. This trait was maintained through 9 months of passage but then was lost.  相似文献   

6.
Herbivory by large animals is known to function as a selection pressure to increase herbivory resistance within plant populations by decreasing the frequency of genotypes possessing large, erect canopies. However, the increase in herbivory resistance of the remaining genotypes in the population may potentially involve a tradeoff with competitive ability. The perennial bunchgrass Schizachyrium scoparium was grown in a transplant garden to test the hypothesis that late successional plant populations with a history of grazing are at a competitive disadvantage relative to conspecific populations with no history of grazing were found to possess a greater competitive ability than plants with no grazing history in the absence of herbivory. This unexpected response resulted from the capacity of plants with a history of grazing to recruit a greater number of smaller tillers than did plants with no grazing history. This response was only significant when plants with a history of grazing were nondefoliated and grown with the weakest of the mid-successional competitors, indicating that both defoliation and intense interspecific competition can mask the architectural expression of herbivore-induced selection. Individual tillers did not display any architectural differences between plants with contrasting grazing histories other than mean tiller weight. These data confirm that herbivory by domestic cattle may function as a selection pressure to induce architectural variation in grass populations within an ecological time frame (ca <-25 yrs).  相似文献   

7.
N. Rashevsky 《Protoplasma》1933,20(1):180-188
Summary It is shown by thermodynamical considerations, that in general regardless to the particular nature of a cell, there must be two kinds of forces between cells: a force of repulsion, due to metabolism, and a force of attraction, due to irritability. It is shown, that the various geometrical forms, which cellular aggregates may assume under the influence of those forces, correspond in general features to various forms, found in nature. In conclusion I wish to express my profound indebtedness to ProfessorDavenport Hooker, for frequent discussions of the subject and a great amount of valuable information. With 1 Text-figure  相似文献   

8.
No consensus exists for the homology and terminology of the male genitalia of the Hexapoda despite over a century of debate. Based on dissections and the literature, genital skeletomusculature was compared across the Hexapoda and contrasted with the Remipedia, the closest pancrustacean outgroup. The pattern of origin and insertion for extrinsic and intrinsic genitalic musculature was found to be consistent among the Ectognatha, Protura, and the Remipedia, allowing for the inference of homologies given recent phylogenomic studies. The penis of the Hexapoda is inferred to be derived from medially-fused primary gonopods (gonopore-bearing limbs), while the genitalia of the Ectognatha are inferred to include both the tenth-segmental penis and the ninth-segmental secondary gonopods, similar to the genitalia of female insects which comprise gonopods of the eighth and ninth segments. A new nomenclatural system for hexapodan genitalic musculature is presented and applied, and a general list of anatomical concepts is provided. Novel and refined homologies are proposed for all hexapodan orders, and a series of groundplans are postulated. Emphasis is placed on the Endopterygota, for which fine-grained transition series are hypothesized given observed skeletomuscular correspondences.  相似文献   

9.
If life were created by intelligent design, we would indeed age from accumulation of molecular damage. Repair is costly and limited by energetic resources, and we would allocate resources rationally. But, albeit elegant, this design is fictional. Instead, nature blindly selects for short-term benefits of robust developmental growth. “Quasi-programmed” by the blind watchmaker, aging is a wasteful and aimless continuation of developmental growth, driven by nutrient-sensing, growth-promoting signaling pathways such as MTOR (mechanistic target of rapamycin). A continuous post-developmental activity of such gerogenic pathways leads to hyperfunctions (aging), loss of homeostasis, age-related diseases, non-random organ damage and death. This model is consistent with a view that (1) soma is disposable, (2) aging and menopause are not programmed and (3) accumulation of random molecular damage is not a cause of aging as we know it.  相似文献   

10.
Adaptation is conventionally regarded as occurring at the level of the individual organism. However, in recent years there has been a revival of interest in the possibility for group adaptations and superorganisms. Here, we provide the first formal theory of group adaptation. In particular: (1) we clarify the distinction between group selection and group adaptation, framing the former in terms of gene frequency change and the latter in terms of optimization; (2) we capture the superorganism in the form of a ‘group as maximizing agent’ analogy that links an optimization program to a model of a group‐structured population; (3) we demonstrate that between‐group selection can lead to group adaptation, but only in rather special circumstances; (4) we provide formal support for the view that between‐group selection is the best definition for ‘group selection’; and (5) we reveal that mechanisms of conflict resolution such as policing cannot be regarded as group adaptations.  相似文献   

11.
Summary A metatheoretical and historiographical re-analysis of the Evolutionary Synthesis (the process) and the Synthetic Theory (the result) leads to the following conclusion: The Synthetic Theory is not a reductionistic, but rather a structuralistic theory with a limited range of relevant hierarchical levels. Historically the Synthesis was not a sudden event but a rational long-term project carried out between 1930 and 1950 by a large number of biologists in several countries. In the second part of our paper the contributions of several German biologists to the Synthesis are analyzed.  相似文献   

12.
Community ecology entered the 1970s with the belief that niche theory would supply a general theory of community structure. The lack of wide-spread empirical support for niche theory led to a focus on models specific to classes of communities such as lakes, intertidal communities, and forests. Today, the needs of conservation biology for metrics of “ecological health” that can be applied across types of communities prompts a renewed interest in the possibility of general theory for community ecology. Disputes about the existence of general patterns in community structure trace at least to the 1920s and continue today almost unchanged in concept, although now expressed through mathematical modeling. Yet, a new framework emerged in the 1980s from findings that community composition and structure depend as much on the processes that bring species to the boundaries of a community as by processes internal to a community, such as species interactions and co-evolution. This perspective, termed “supply-side ecology”, argued that community ecology was to be viewed as an “organic earth science” more than as a biological science. The absence of a general theory of the earth would then imply a corresponding absence of any general theory for the communities on the earth, and imply that the logical structure of theoretical community ecology would consist of an atlas of models special to place and geologic time. Nonetheless, a general theory of community ecology is possible similar in form to the general theory for evolution if the processes that bring species to the boundary of a community are analogized to mutation, and the processes that act on the species that arrive at a community are analogized to selection. All communities then share some version of this common narrative, permitting general theorems to be developed pertaining to all ecological communities. Still, the desirability of a general theory of community ecology is debatable because the existence of a general theory suppresses diversity of thought even as it allows generalizations to be derived. The pros and cons of a general theory need further discussion.  相似文献   

13.
General theories (GT) are reductionist explications of apparently independent facts. Here, in reviewing the literature, I develop a GT to simplify the cluttered landscape of cancer therapy targets by revealing they cluster parsimoniously according to only a few underlying principles. The first principle is that targets can be only exploited by either or both of two fundamentally different approaches: causality‐inhibition, and ‘acausal’ recognition of some marker or signature. Nonetheless, each approach must achieve both of two separate goals, efficacy (reduction in cancer burden) and selectivity (sparing of normal cells); if the mechanisms are known, this provides a definition of rational treatment. The second principle is target fragmentation, whereby the target may perform up to three categoric functions (cytoreduction, modulation, cytoprotection), potentially mediated by physically different target molecules, even on different cell types, or circulating freely. This GT remains incomplete until the minimal requirements for cure, or alternatively, proof that cure is impossible, become predictable.  相似文献   

14.
15.
Sexual conflict appears to be a powerful force in evolution. We suggest that selection theory can readily be adapted for cases of sexual conflict and illustrate how it can provide a new perspective on what traits cause conflict and might respond to its presence. Use of selection theory resolves some terminological confusion, provides operational measures of conflict and generates a conceptual tool for parsing the causes and consequences of conflict in complex systems of male–female interactions.  相似文献   

16.
One of the enduring puzzles in biology and the social sciences is the origin and persistence of intraspecific cooperation and altruism in humans and other species. Hundreds of theoretical models have been proposed and there is much confusion about the relationship between these models. To clarify the situation, we developed a synthetic conceptual framework that delineates the conditions necessary for the evolution of altruism and cooperation. We show that at least one of the four following conditions needs to be fulfilled: direct benefits to the focal individual performing a cooperative act; direct or indirect information allowing a better than random guess about whether a given individual will behave cooperatively in repeated reciprocal interactions; preferential interactions between related individuals; and genetic correlation between genes coding for altruism and phenotypic traits that can be identified. When one or more of these conditions are met, altruism or cooperation can evolve if the cost-to-benefit ratio of altruistic and cooperative acts is greater than a threshold value. The cost-to-benefit ratio can be altered by coercion, punishment and policing which therefore act as mechanisms facilitating the evolution of altruism and cooperation. All the models proposed so far are explicitly or implicitly built on these general principles, allowing us to classify them into four general categories.  相似文献   

17.
Gardner (2015) recently developed a model of a ‘Genetical Theory of Multilevel Selection, which is a thoughtfully developed, but flawed model. The model's flaws appear to be symptomatic of common misunderstandings of the multi level selection (MLS) literature and the recent quantitative genetic literature. I use Gardner's model as a guide for highlighting how the MLS literature can address the misconceptions found in his model, and the kin selection literature in general. I discuss research on the efficacy of group selection, the roll of indirect genetic effects in affecting the response to selection and the heritability of group‐level traits. I also discuss why the Price multilevel partition should not be used to partition MLS, and why contextual analysis and, by association, direct fitness are appropriate for partitioning MLS. Finally, I discuss conceptual issues around questions concerning the level at which fitness is measured, the units of selection, and I present a brief outline of a model of selection in class‐structured populations. I argue that the results derived from the MLS research tradition can inform kin selection research and models, and provide insights that will allow researchers to avoid conceptual flaws such as those seen in the Gardner model.  相似文献   

18.
Synthetic biology has the potential to contribute breakthrough innovations to the pursuit of new global health solutions. Wishing to harness the emerging tools of synthetic biology for the goals of global health, in 2011 the Bill & Melinda Gates Foundation put out a call for grant applications to “Apply Synthetic Biology to Global Health Challenges” under its “Grand Challenges Explorations” program. A highly diverse pool of over 700 applications was received. Proposed applications of synthetic biology to global health needs included interventions such as therapeutics, vaccines, and diagnostics, as well as strategies for biomanufacturing, and the design of tools and platforms that could further global health research.  相似文献   

19.
Summary The divergence pattern of mammalian ZFY-related genes from human (ZFY and ZFX) and mouse (Zfy-1 and Zfx) was reexamined on the basis of nucleotide substitutions at the synonymous codon-alternating positions. It is possible to explain the unusual divergence pattern of the mammalian Y-linked ZF genes by interchromosomal gene conversion by X-linked ZF genes. Furthermore, the rates of evolution of mammalian X- and Y-linked ZF genes were shown to agree well with those expected from our model. Offprint requests to: T. Miyata  相似文献   

20.
Cope's rule, the tendency for species within a lineage to evolve towards larger body size, has been widely reported in the fossil record, but the mechanisms leading to such phyletic size increase remain unclear. Here we show that selection acting on individual organisms generally favors larger body size. We performed an analysis of the strength of directional selection on size compared with other quantitative traits by evaluating 854 selection estimates from 42 studies of contemporaneous natural populations. For size, more than 79% of selection estimates exceed zero, whereas for other morphological traits positive and negative values are similar in frequency. The selective advantage of increased size occurs for traits implicated in both natural selection (e.g., differences in survival) and sexual selection (e.g., differences in mating success). The predominance of positive directional selection on size within populations could translate into a macroevolutionary trend toward increased size and thereby explain Cope's rule.  相似文献   

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