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1.
Proponents of two axioms of biological evolutionary theory have attempted to find justification by reference to nonequilibrium thermodynamics. One states that biological systems and their evolutionary diversification are physically improbable states and transitions, resulting from a selective process; the other asserts that there is an historically constrained inherent directionality in evolutionary dynamics, independent of natural selection, which exerts a self-organizing influence. The first, the Axiom of Improbability, is shown to be nonhistorical and thus, for a theory of change through time, acausal. Its perception of the improbability of living states is at least partially an artifact of closed system thinking. The second, the Axiom of Historically Determined Inherent Directionality, is supported evidentially and has an explicit historical component. Historically constrained dynamic populations are inherently nonequilibrium systems. It is argued that living, evolving systems, when considered to be historically constrained nonequilibrium systems, do not appear improbable at all. Thus, the two axioms are not compatible. Instead, the Axiom of Improbability is considered to result from an unjustified attempt to extend the contingent proximal actions of natural selection into the area of historical, causal explanations. It is thus denied axiomatic status, and the effects of natural selection are subsumed as an additional level of constraint in an evolutionary theory derived from the Axiom of Historically Determined Inherent Directionality.  相似文献   

2.
Qian H  Beard DA 《Biophysical chemistry》2005,114(2-3):213-220
The principles of thermodynamics apply to both equilibrium and nonequilibrium biochemical systems. The mathematical machinery of the classic thermodynamics, however, mainly applies to systems in equilibrium. We introduce a thermodynamic formalism for the study of metabolic biochemical reaction (open, nonlinear) networks in both time-dependent and time-independent nonequilibrium states. Classical concepts in equilibrium thermodynamics-enthalpy, entropy, and Gibbs free energy of biochemical reaction systems-are generalized to nonequilibrium settings. Chemical motive force, heat dissipation rate, and entropy production (creation) rate, key concepts in nonequilibrium systems, are introduced. Dynamic equations for the thermodynamic quantities are presented in terms of the key observables of a biochemical network: stoichiometric matrix Q, reaction fluxes J, and chemical potentials of species mu without evoking empirical rate laws. Energy conservation and the Second Law are established for steady-state and dynamic biochemical networks. The theory provides the physiochemical basis for analyzing large-scale metabolic networks in living organisms.  相似文献   

3.

We give a review on the landscape theory of the equilibrium biological systems and landscape-flux theory of the nonequilibrium biological systems as the global driving force. The emergences of the behaviors, the associated thermodynamics in terms of the entropy and free energy and dynamics in terms of the rate and paths have been quantitatively demonstrated. The hierarchical organization structures have been discussed. The biological applications ranging from protein folding, biomolecular recognition, specificity, biomolecular evolution and design for equilibrium systems as well as cell cycle, differentiation and development, cancer, neural networks and brain function, and evolution for nonequilibrium systems, cross-scale studies of genome structural dynamics and experimental quantifications/verifications of the landscape and flux are illustrated. Together, this gives an overall global physical and quantitative picture in terms of the landscape and flux for the behaviors, dynamics and functions of biological systems.

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4.
The present work is intended to demonstrate that most of the paradoxes, controversies, and contradictions accumulated in molecular and cell biology over many years of research can be readily resolved if the cell and living systems in general are re-interpreted within an alternative paradigm of biological organization that is based on the concepts and empirical laws of nonequilibrium thermodynamics. In addition to resolving paradoxes and controversies, the proposed re-conceptualization of the cell and biological organization reveals hitherto unappreciated connections among many seemingly disparate phenomena and observations, and provides new and powerful insights into the universal principles governing the emergence and organizational dynamics of living systems on each and every scale of biological organizational hierarchy, from proteins and cells to economies and ecologies.  相似文献   

5.
The stochastic theory of a nonlinear game is presented which incorporates some of the essential properties of living systems: metabolism, reproduction and mutability. The steady state distribution function as well as the complete time development are given explicitly. The second law of thermodynamics is generalized to a certain class of nonequilibrium systems. An order parameter is introduced as a measure of the system's internal organization. From the point of view of phase transition theory, the model exhibits a transition at the absolute zero of temperature, with critical behaviour showing up in the low temperature region.  相似文献   

6.
A large body of experimental evidence indicates that the specific molecular interactions and/or chemical conversions depicted as links in the conventional diagrams of cellular signal transduction and metabolic pathways are inherently probabilistic, ambiguous and context-dependent. Being the inevitable consequence of the dynamic nature of protein structure in solution, the ambiguity of protein-mediated interactions and conversions challenges the conceptual adequacy and practical usefulness of the mechanistic assumptions and inferences embodied in the design charts of cellular circuitry. It is argued that the reconceptualization of molecular recognition and cellular organization within the emerging interpretational framework of self-organization, which is expanded here to include such concepts as bounded stochasticity, evolutionary memory, and adaptive plasticity offers a significantly more adequate representation of experimental reality than conventional mechanistic conceptions do. Importantly, the expanded framework of self-organization appears to be universal and scale-invariant, providing conceptual continuity across multiple scales of biological organization, from molecules to societies. This new conceptualization of biological phenomena suggests that such attributes of intelligence as adaptive plasticity, decision-making, and memory are enforced by evolution at different scales of biological organization and may represent inherent properties of living matter.  相似文献   

7.
The goal of modern taxonomy is to understand the relationships of living organisms in terms of evolutionary descent. Thereby, the relationships between living organisms are understood in terms of nested clades—every time a speciation event takes place, two new clades are produced. Life comprises three domains of living organisms, these are the Bacteria, the Archaea and the Eukaryota. Within the eukaryotic domain, the fungi form a monophyletic group of the eukaryotic crown group and are thus high up in the evolutionary hierarchy of life. Fungus-like organisms possess certain morphological features of fungi, such as the hyphal organization of the Oomycota or the spores and reproductive structures inside a fructification of plasmodiophorids (Plasmodiophoromycota) and slime moulds (Mycetozoa). The first group are algae which secondarily lost their plastids during evolution and contain cellulose in their cell walls. Both osmotrophic phyla, the Oomycota and the Plasmidiophoromycota belong to the Chromista and Rhizaria, respectively, whereas the last group, the cellular and plasmodial slime moulds (Mycetozoa) are phagotrophic amoeboid protists belonging to the Amoebozoa. These fungus-like organisms are not considered further in this review. The Fungi sensu stricto comprise a heterogenous, often inconspicuous group of microorganisms which (1) are primarily heterotrophic with an (2) osmotrophic style of nutrition containing (3) chitin and its derivatives in the cell wall. This review discusses species concepts and current strategies in fungal taxonomy, phylogenetic affiliations of miscellaneous fungus-like groups like the microsporidia, perspectives of fungal nomenclature, and their impact on natural product research.  相似文献   

8.
Ecologic systems, which are involved mainly in the processing of energy and materials, are actually nested one inside another—they are simultaneously parts and wholes. This fundamental hierarchical organization is easy to detect in nature but has been undervalued by ecologists as a source of new insights about the structure and development of ecosystems and as a means of understanding the crucial connections between ecologic processes and large-scale evolutionary patterns. These ecologic systems include individual organisms bundled into local populations, populations as functional components of local communities or ecosystems, local systems making up the working parts of larger regional ecosystems, and so on, right up to the entire biosphere. Systems at any level of organization can be described and interpreted based on aspects of scale (size, duration, and “membership” in more inclusive entities), integration (all the vital connections both at a particular focal level and across levels of hierarchical organization), spatiotemporal continuity (the “life history” of each system), and boundaries (either membranes, skins, or some other kind of border criterion). Considering hierarchical organization as a general feature of ecologic systems could reinvigorate theoretical ecology, provide a realistic scaling framework for paleoecologic studies, and – most importantly – forge new and productive connections between ecology and evolutionary theory.  相似文献   

9.
Life on earth is governed by light, chemical reactions, and the second law of thermodynamics, which defines the tendency for increasing entropy as an expression of disorder or randomness. Life is an expression of increasing order, and a constant influx of energy and loss of entropic wastes are required to maintain or increase order in living organisms. Most of the energy for life comes from sunlight and, thus, photosynthesis underlies the survival of all life forms. Oxygenic photosynthesis determines not only the global amount of enthalpy in living systems, but also the composition of the Earth’s atmosphere and surface. Photosynthesis was established on the Earth more than 3.5 billion years ago. The primordial reaction center has been suggested to comprise a homodimeric unit resembling the core complex of the current reaction centers in Chlorobi, Heliobacteria, and Acidobacteria. Here, an evolutionary scenario based on the known structures of the current reaction centers is proposed.  相似文献   

10.
Biogeochemistry is the study of how living systems in combination with abiotic reactions process and cycle mass and energy on local, regional, and global scales (Schlesinger, 1997). Understanding how these biogeochemical cycles function and respond to perturbations has become increasingly important, as anthropogenic impacts have significantly altered many of these cycles (Galloway and Cowling, 2002; Houghton et al., 2002). Biogeochemistry is strongly governed by microbial processes, and it appears to closely follow thermodynamic constraints in that electron acceptor (O(2), NO(3)(-), SO(4)(2-), etc.) utilization closely follows a priori expectations based on energetics (Vallino et al., 1996; Hoehler et al., 1998; Jakobsen and Postma, 1999; Amend and Shock, 2001). Consortiums of microorganisms seem to have evolved to exploit chemical potentials wherever they exist in the environment, as manifested by the recent discovery of anaerobic methane oxidation by sulfate (Boetius et al., 2000) or sulfide oxidation by nitrate (Schulz et al., 1999). Three and a half billion years of natural selection have produced living systems capable of degrading most chemical potentials. We may therefore ask: If all ecosystem niche space is filled, is the biogeochemistry we observe in the environment dependent on the organisms that occupy that environment, or is the biogeochemistry determined by fundamental forces, with the evolution of living systems being the implementation of those forces? Recent developments in nonequilibrium thermodynamics (NET) are beginning to support the latter alternative, and advances in genomics are allowing us to explore microbial consortiums in detail. Taking advantage of ideas being suggested by NET, we have developed a modeling framework that views microbial consortiums as an inter-species distributed metabolic network. When combined with experimental observations, the model should help us test hypotheses that govern how living systems function.  相似文献   

11.
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   

12.
The study of culture and cultural selection from a biological perspective has been hampered by the lack of any firm theoretical basis for how the information for cultural traits is stored and transmitted. In addition, the study of any living system with a decentralized or multi-level information structure has been somewhat restricted due to the focus in genetics on the gene and the particular hereditary structure of multicellular organisms. Here a different perspective is used, one which regards living systems as self-constructing energy users that utilize their genome as a library of information, making the genetic system just another component that adds fitness to the overall integrated unit. In this framework, basic fitness is measured as the ability to gather energy for growth and reproduction, and the fitness of the genetic system is broken down into two aspects: first, the effectiveness in searching for new somatic functional information, and second, the effectiveness in searching for better structures to store and process information. With this more generalized perspective, major evolutionary transitions to higher levels of organization become competitions between different information structures; furthermore the functioning and fitness of cultural systems can be more easily described and compared with other modes of information storage within biological systems. Modern technological societies are self-constructing systems that rely on written (symbolic) information storage and very complex algorithms that effectively search for variation with a high probability of successful selection. These systems are currently competing with traditional organic systems, and this competition constitutes the latest major evolutionary transition. Upon comparison of the energy-gathering potential of symbolic-based systems with DNA-based life, it appears that symbolic systems have a tremendous fitness potential and the current shift to a higher level of selection may be as significant and far-reaching as any of the previous major evolutionary transitions.  相似文献   

13.
Scientists use time to describe and research the universe in which humans live. Geologists and evolutionary biologists often use time scales in the millions to billions of years while biochemists and molecular biologists use time scales in the milliseconds or less. The atom smashers use time scales that are almost the speed of light. However, in some areas of research such as molecular-based activities in cells, it is very challenging to obtain data sets in molecular time scales. This has been a challenge to obtaining accurate and precise measurements at the cell and molecular levels of organization in living organisms. Measurements of specific cellular and molecular activities are often made over time scales longer than the actual molecular events. The data sets obtained become estimates over seconds, minutes and hours and not measurements over milli- and nanoseconds. The question can then be posed — how representative and accurate are our data sets when the time scales are not synchronized with the actual living events? In this article, the role of time scales in scientific research and our understanding of living microorganisms are examined with an emphasis on cell and molecular time scales.  相似文献   

14.
Invasive species provide unique and useful systems by which to examine various ecological and evolutionary issues, both in terms of the effects on native environments and the subsequent evolutionary impacts. While biological invasions are an increasing agent of change in aquatic systems, alien species also act as vectors for new parasites and diseases. To date, colonizations by hosts and parasites have not been treated and reviewed together, although both are usually interwoven in various ways and may have unpredictable negative consequences. Fish are widely introduced worldwide and are convenient organisms to study parasites and diseases. We report a global overview of fish invasions with associated parasitological data. Data available on marine and freshwater are in sharp contrast. While parasites and diseases of inland freshwater fish, ornamental, reared and anadromous fish species are well documented, leading to the emergence of several evolutionary hypotheses in freshwater ecosystems during the last decade, the transfer of such organisms are virtually unexplored in marine ecosystems. The paucity of information available on the parasites of introduced marine fish reflects the paucity of information currently available on parasites of non-indigenous species in marine ecosystems. However, such information is crucial as it can allow estimations of the extent to which freshwater epidemiology/evolution can be directly transferred to marine systems, providing guidelines for adapting freshwater control to the marine environment.  相似文献   

15.
Living cells are spatially bounded, low entropy systems that, although far from thermodynamic equilibrium, have persisted for billions of years. Schrödinger, Prigogine, and others explored the physical principles of living systems primarily in terms of the thermodynamics of order, energy, and entropy. This provided valuable insights, but not a comprehensive model. We propose the first principles of living systems must include: (1) Information dynamics, which permits conversion of energy to order through synthesis of specific and reproducible, structurally-ordered components; and (2) Nonequilibrium thermodynamics, which generate Darwinian forces that optimize the system. Living systems are fundamentally unstable because they exist far from thermodynamic equilibrium, but this apparently precarious state allows critical response that includes: (1) Feedback so that loss of order due to environmental perturbations generate information that initiates a corresponding response to restore baseline state. (2) Death due to a return to thermodynamic equilibrium to rapidly eliminate systems that cannot maintain order in local conditions. (3) Mitosis that rewards very successful systems, even when they attain order that is too high to be sustainable by environmental energy, by dividing so that each daughter cell has a much smaller energy requirement. Thus, nonequilibrium thermodynamics are ultimately responsible for Darwinian forces that optimize system dynamics, conferring robustness sufficient to allow continuous existence of living systems over billions of years.  相似文献   

16.
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18.
农业组织与有害生物风险管理研究综述   总被引:1,自引:0,他引:1  
郑思宁  魏炜  郑逸芳 《生态学报》2019,39(2):460-473
随着全球气候变暖、农药滥用、外来有害生物入侵等因素,我国农业病虫害逐年呈快速增长之势。而以广大农户家庭、合作组织、农业企业为单元的社会灾害管理系统是生物灾害管理体系中重要的组成部分,但却存在着规模分散、管理混乱等问题。有害生物是公共品,具有外部性的特征,而我国分散化的管理组织形式,不利于对有害生物的统一治理。现阶段我国关于农业组织化对有害生物防控影响的文献较少,为此,通过分别梳理农业组织风险管理和有害生物风险管理的研究进展,探讨不同农业组织风险管理、有害生物风险管理、有害生物造成的经济损失以及有害生物综合治理的方法与模式。在未来的研究中,应进一步加强不同农业组织对有害生物防控效果、有害生物造成经济损失的影响因素、不同农业组织对有害生物"统防统治"参与行为的研究,通过农业组织化防控治理体系的改革,提升有害生物的防控效率,以更好的为政府相关部门决策提供必要的参考依据。  相似文献   

19.
The living forms represented in this paper are sets of parts that spontaneously increase in organization. Their organizations are measured by an information-theoretic function derived from the work of Boltzmann and Shannon. We briefly review its derivation in the context of the troubled role of mathematics in biology, and then define the function. We illustrate its nature by measuring the 22 different organizations of a set of eight things; and we facilitate its use by defining the parameters that determine an amount of organization. The measure is then applied to show that the organization of limb pairs on free-living arthropods, based on data given by Cisne, confirms a pattern of increasing organization in their evolution from the Cambrian era to the present. Further applications measure the changes in organizations of ideal (theoretical) life forms, and contrasting changes in inanimate systems. Our main results represent the reproduction of unicellular organisms, and the formation of hierarchies, as processes of increasing organization.  相似文献   

20.
This review paper deals with the problem of the design and operation of marine reserves in the context of modern views on the hierarchical organization of marine ecosystems. The state of the art in the theoretical aspect of the establishment and development of marine protected areas (MPAs) is discussed. Despite the increasing number of publications on MPAs, which are mainly focused on social and economic issues, studies devoted to the ecological bases for the establishment and operation of marine reserves are still scarce. However, the low efficiency of the existing MPAs and their systems may be a result of the lack of an ecological background in MPA designs. Recent threats to the diversity of marine organisms are analyzed, and changes in the relative significance of anthropogenic factors affecting the marine biological diversity are assessed. The hierarchical nature of and the existence of characteristic spatial scales in the marine ecosystems are critical issues that must be taken into account together with scale-oriented analysis of the anthropogenic threats. On the basis of the scale-oriented concept of the marine ecosystems, new theoretical approaches to the design and operation of MPAs are formulated. In particular, theoretical bases for the estimation of the minimal size of marine reserves and a hierarchical approach to the design of MPA systems are proposed. Formal schemes of classification of sea bottom communities (The Marine Habitat Classification for Britain and Ireland and EUNIS) are discussed.  相似文献   

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