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Conclusions We began our survey at a time when Ehrenberg's functional principles concerning the design of all organisms prevailed in interpreting the taxonomic place and internal structure of Infusoria. Other options existed, such as Dujardin's sarcode theory and Siebold's cellular analogy, but these were not persuasive for reasons both relevant to and in addition to the microscopic observations. By mid-century other considerations, including the continuing search for complex life cycles and manifestations of sex, dictated the microscopist's rendering of infusorians. Müller and his students saw spermatozoa and gonads; Stein envisioned alternating generations and generative nuclei; Balbiani found sexual behavior in the events of conjugation; and all interpreted the nuclei and nucleoli as gonads or gonadal products. Evolutionary theory provided a fourth dimension. Obsessed with phylogenies, particularly when joined with the germ-layer theory of development, Haeckel emphasized a structural interpretation and found a considerably altered cell theory ready to fill the breach.By the mid-1870s advances in cytology secured Siebold's original analogy. Infusorians now became single-celled organisms, the first in a long phylogenetic sequence that led to the highest metazoans. The analogy allowed Bütschli to invoke another biological principle, the physiological division of labor, to reinterpret the origin of the bisexual state. The ghost of Ehrenberg's polygastric theory had completely vanished.  相似文献   

3.
This article identifies key aspects of the metaphysical paradigms under which European Paleolithic archaeological research is conducted and contrasts the anthropological approaches typical of anglophone New World workers with those of the "his- tory-like" natural science-based traditions of Latin Europe. Because the Middle–Upper Paleolithic transition in Europe is thought by many to correspond to the biological replacement of Neandertals by modern humans over the ten millennia bracketing 40 kyr B.P., generalizations about the archaeological transition invoked in support of biological replacement are examined and are found to lack empirical support. Patterns in lithic technology, typology, raw material variability, reduction strategies, blank frequencies, bone and antler technologies, Paleolithic art, subsistence strategies, and settlement patterns all indicate a temporal-spatial mosaic of changing monitors of human adaptation over the transition interval that cannot be reconciled with any construal of a relatively abrupt and complete biological replacement. [Key words: conceptual frameworks, research traditions, archaeological systematic, Middle–Upper Paleolithic transition, Neandertals, adaptation]  相似文献   

4.
Economic intensification has been documented in a diversity of small-scale societies. The existing archaeological theory concerning such intensification has tended to privilege economic and political explanations and largely ignores social action and ritual performance as motivations for economic change. In this article, 1 use both ethnographic and archaeological data to argue that ceremonial feasting and the need for socially valued goods, which are critical for ritual performance and necessary for a variety of social transactions, create the demand that underwrites and sustains economic intensification in small-scale societies. Food for large-scale feasts is acquired through the intensification of food production and procurement targeted specifically for feasting, rather than from the surplus available from routine subsistence production. Large-scale demands for socially valued goods tend to result in specialization on the production of "extraordinary" material culture, which is characterized by two modes of circulation, in networks of social obligations or as offerings in sacred locations. [Key words.craft specialization, exchange, feasting, ritual]  相似文献   

5.
Calcium and other alkaline earth cations change the electrostatic potential adjacent to negatively charged bilayer membranes both by accumulating in the aqueous diffuse double layer adjacent to the membrane and by adsorbing to the phospholipids. The effects of these cations on the electrostatic potential are described adequately by the Gouy-Chapman-Stern theory. We report the results of experiments with ethane-bis-trimethylammonium, a cation that has been termed "dimethonium" or "ethamethonium" in analogy with hexamethonium (hexane-1,6-bis-trimethylammonium) and decamethonium (decane-1,10-bis-trimethylammonium). We examined the effect of dimethonium on the zeta potential of multilamellar vesicles formed from the negative lipid phosphatidylserine (PS) and from 5:1 phosphatidylcholine/phosphatidylserine mixtures in solutions containing 0.1, 0.01 and 0.001 M sodium, cesium, or tetramethylammonium chloride. We also examined the effect of dimethonium on the conductance of planar PS bilayer membranes and the 31P NMR signal from sonicated PS vesicles formed in 0.1 M NaCl. We found no evidence that dimethonium adsorbs specifically to bilayer membranes. All the results, except for those obtained with vesicles of low charge density formed in a solution with a high salt concentration, are consistent with the predictions of the Gouy-Chapman theory. We conclude that dimethonium, which does not have the pharmacological effects of hexamethonium and decamethonium, is a useful divalent cation for physiologists interested in investigating electrostatic potentials adjacent to biological membranes.  相似文献   

6.
In models of multi-level selection, the property of Darwinian fitness is attributed to entities at more than one level of the biological hierarchy, e.g. individuals and groups. However, the relation between individual and group fitness is a controversial matter. Theorists disagree about whether group fitness should always, or ever, be defined as total (or average) individual fitness. This paper tries to shed light on the issue by drawing on work in social choice theory, and pursuing an analogy between fitness and utility. Social choice theorists have long been interested in the relation between individual and social utility, and have identified conditions under which social utility equals total (or average) individual utility. These ideas are used to shed light on the biological problem.  相似文献   

7.
Means, Advantages and Limits of Merging Biology with Technology   总被引:3,自引:0,他引:3  
The natural world spent billions of years in solution-finding during evolution, which could benefit Technology. How do we put that in a nutshell? Biological systems are more complex than the most complex current technology. Any given functiofi and effect are simultaneously coordinated and linked with others at many levels of biological organisation-from cell organelle to organism, to population and ecosystem. Technology does not have tools to deal with the complexity and “goalintendedness“ of living systems. But limits for interaction exist on both sides-Biological science itself is also too empirical and not mature enough to provide a solid base for correlating living with technical systems. Moving towards a synthesis, where engineers can utilize the vast amount of available biological data, we suggest using a tool called “Theory of Inventive Problem Solving“ (TRIZ) and clarifying some important methodological issues, which have not previously been recognised in bionic engineering: 1) Requirement for more appropriate definitions of “system“, “effect“, “function“, “law“ and “rule“. 2) Requirement for understanding or even measuring the degree of contradiction or analogy between functions in biological and artificial and/or non-living engineering system-there is no simple direct correlation between what engineers find useful and what biology does.  相似文献   

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Conclusion De Vries' mutation theory has not stood the test of time. The supposed mutations of Oenothera were in reality complex recombination phenomena, ultimately explicable in Mendelian terms, while instances of large-scale mutations were found wanting in other species. By 1915 the mutation theory had begun to lose its grip on the biological community; by de Vries' death in 1935 it was almost completely abandoned. Yet, as we have seen, during the first decade of the present century it achieved an enormous popularity. As this paper has tried to suggest, one of the principal reasons for this was that de Vries' theory served as a banner around which a whole crowd of disaffected Darwinians or anti-Darwinians could rally. However, not all of those who favored de Vries did so for quite the same reasons. Underlying the multitude of views ran several common threads: a dissatisfaction with current Darwinian theory born out of misunderstanding natural selection, a general misunderstanding of the nature of species, and a prejudice against speculative, nontestable theories in biology.Supporters of de Vries were not the only opponents of Darwinism, nor was the mutation theory the only alternative to natural selection. In the early twentieth century a number of theories had been proposed to explain away the problems which Darwin had left unsolved. There was the idea of orthogenesis, championed by the American paleontologists Cope, Osborn and others; organic selection (or orthoplasy) was championed by M. M. Baldwin and C. Lloyd Morgan; there were the concepts of convergent evolution proposed by Hermann Friedmann, the theory of physiological selection by John George Romanes, and the concepts of reproductive divergence by H. M. Vernon. Virtually none of these men either accepted or were strong supporters of the de Vriesian theory, for each had his own particular ism to advocate as the major factor in evolution. The existence of a large number of such theories, each purporting to be the explanation, was characteristic of evolutionary theory at the turn of the century. It is to a large extent the emphasis on such fragmentary concepts that retarded development of the comprehensive theory of evolution which emerged in the 1920's and 1930's. For the historian, however, a study of these alternative theories is instructive in trying to understand the inherent difficulties which Dawwinian theory posed to biologists at the time. De Vries' mutation theory serves historically as a mirror to reflect the critical mood of a generation hostile to the theory of natural selection.It has often been claimed that it was impossible to understand the mechanism of natural selection until it could be placed in genetic and mathematical terms. It is certainly true that great strides have been made in population genetics and the treatment of evolutionary concepts with mathematical tools in the last forty years. But the very people who developed the genetical and mathematical approach to evolution were already convinced of the essential correctness of Darwinian theory before they started. Advances in an understanding of Mendelian heredity aided greatly in solving one important issue for evolutionists: the origin of variations. And the rigor with which selection acted could best be studied by observing changes in gene frequencies (calculated mathematically) over a number of generations. But as this paper has shown, two of the basic problems which biologists faced in evaluating Darwinian theory at the turn of the century-the nature of species, and the criteria of what constituted an acceptable explanation in biological science-could not be answered directly by mathematics. What mathematical and genetical theory did do was to help convince the skeptics of the validity of the Darwinian proposition.The change in explanatory criteria which many hailed as de Vries' most important contribution to evolutionary theory seems to have been part of a general emergence of twentieth-century biology from the domination of theorizers in the nineteenth. It also marked the emergence of America from the domination of biological, and particularly evolutionary, influence of Europeans. The change occurred in three areas: in the kinds of questions asked: testable versus non-testable; in the kind of data sought: quantitative versus qualitative; and in the kinds of theories proposed: analytical and reductive—the attempt to see complex processes in terms of simpler components-as opposed to synthetic and speculative. Although ultimately wrong in his idea, de Vries and his theories rode high on the wave of experimentalism which was the harbinger of a new era in evolutionary theory.Preparation of this paper has been aided by a grant from National Science Foundation (GS 1832).  相似文献   

10.
The adequacy of Elliott Sober’s analogy between classical mechanics and evolutionary theory—according to which both theories explain via a zero-force law and a set of forces that alter the zero-force state—has been criticized from various points of view. I focus here on McShea and Brandon’s claim that drift shouldn’t be considered a force because it is not directional. I argue that there are a number of different theses that could be meant by this, and show that one of those theses—the idea that drift cannot bias populations to be taken somewhere in the evolutionary space from one generation to the next—is actually false. Not only has this thesis been implicitly assumed in the discussion of the force analogy thus far, but it is also commonly found in a wider range of philosophical and biological texts. I argue that correcting this view, and the usual images associated with it, will thereby bring heuristic benefits that impact the force analogy discussion, but that also go beyond it.  相似文献   

11.
The three monotheistic cultures have many common institutions and some of them germinated in pre-monarchic Israel. Reasonably, the essential institutions were in place at that starting point; this work explores the possibility that the Sabbath is one of these institutions. Our mathematical examination points to the potential cultural, civic, and social role of the weekly Sabbath, that is, the Sabbath institution, in controlling deviation from social norms. It begins with an analogy between spread of transgression (defined as lack of conformity with social norms) and of biological infection. Borrowing well-known mathematical methods, we derive solution sets of social equilibrium and study their social stability. The work shows how a weekly Sabbath could in theory enhance social resilience in comparison with a similar assembly with a more natural and longer period, say between New Moon and Full Moon. The examination reveals that an efficient Sabbath institution has the potential to ensure a stable organization and suppress occasional appearances of transgression from cultural norms and boundaries. The work suggests the existence of a sharp threshold governed by the “Basic Sabbath Number ש0”—a critical observance of the Sabbath, or large enough ש0, is required to ensure suppression of transgression. Subsequently, the model is used to explore an interesting question: how old is the Sabbath? The work is interdisciplinary, combining anthropological concepts with mathematical analysis and with archaeological parallels in regards to the findings.

Electronic supplementary material

The online version of this article (doi:10.1007/s10867-014-9373-9) contains supplementary material, which is available to authorized users.  相似文献   

12.
Within and between tombs at the 1,000-year-old site of Huaca Loro on north coastal Peru, interment characteristics vary to an intriguing degree. Following and elaborating upon prior intracemetery studies, biological relatedness among associated burial groupings was assessed using 23 dental characters (assuming familial allele segregation) for 29 individuals. Biological patterning was based on multivariate distance between individuals using all traits, rather than the previously widespread reliance upon univariate comparison of each trait separately within samples. This multivariate approach did seem more informative. Statistically significant variation of biological similarities and dissimilarities corresponded to spatial groupings and also to various specific archaeological indications of the cohesiveness, or lack thereof, of interment pattern. The partition of biological distances among tombs at Huaca Loro supports the archaeological evidence that the tombs represent a planned elite cemetery.  相似文献   

13.
A kinetic theory of ion transport across cell surfaces has been developed in a form analogous to the kinetic theory of electron transport across solid-liquid interfaces of biological particles. The ionic theory is based on the observation that, at least in one instance, the voltage-current behavior for ion conduction across a cell surface is describable by the Tafel equation, in analogy to the conduction of electrons across solid-liquid interfaces. The theory predicts that the kinetics of ion transport across cell surfaces should conform to the Elovich rate equation, which is shown to be true for various experimental data. The opinions and conclusions contained in this report are those of the author. They are not to be construed as necessarily reflecting the views or the endorsement of the Navy Department.  相似文献   

14.
Michael Ruse, in Taking Darwin Seriously seeks to establish that taking Darwin seriously requires us to treat morality as subjective and naturalistic. I argue that, if morality is not objective, then we have no good reason for being moral if we can avoid detection and punishment. As a consequence, we will only continue to behave morally as long as we remain ignorant of Ruse's theory, that is, as long as the cat is not let out of the bag. Ruse offers a number of arguments to show that his theory can overcome such problems. I argue that they all fail. Ruse also argues that he can offer a naturalistic account of ethics which steps around the naturalistic fallacy and avoids the confusion of reasons with causes. His principal argument for this view is an analogy between spiritualism and morality. I argue that this analogy fails.  相似文献   

15.
Populations of the Chalcolithic Levant as defined by archaeological excavations has in many cases reinforced the traditional scheme that a number of “races” are present. This scheme is usually based not only on differential cultural traditions as identified by archeologists, but also on the available skeletal evidence as discussed by physical anthropologists. Recently this view has been challenged and it has been suggested that the metrical and anatomical range of variability as identified within Chalcolithic populations can be subsumed into a single population or “racial” range. This paper examines both the available biological and archaeological evidence from the Chalcolithic Levant and concludes that there is no strong archaeological or biological evidence to support a multiple “racial” origin for the Chalcolithic of the Levant.  相似文献   

16.
Comparison of funerary treatment and skeletal biology can be very informative about the interplay of social status and meanings and actual life conditions in ancient communities, but such comparison is rarely done, due in part to the disciplinary separation of bioanthropology and social archaeology in many archaeological traditions. In this paper, we analyze relations between skeletal pathologies and grave goods in a sample of 94 individuals from Pontecagnano (Salerno, Italy, seventh-third centuries BC). The results show that the relationship between health, activity, and social status as expressed in grave goods was complex. Some biological indicators considered typical of "stress" or biological status (enamel hypoplasia, cribra orbitalia, adult stature) bore no relation to social status. Other indicators, particularly those of activity and stress in adult life (trauma, Schmorl's nodes, periostitis), covaried with grave assemblage and help to outline a possible division of labor. As this analysis shows, when skeletal and archaeological data are used in conjunction, the result is a deeper picture of the social and economic life of the community than can be obtained from either source.  相似文献   

17.
Whole-culture or batch synchronization cannot, in theory, produce a synchronized culture because it violates a fundamental law that proposes that no batch treatment can alter the cell-age order of a culture. In analogy with the history of perpetual-motion machines, it is suggested that the study of these whole-culture 'synchronization' methods might lead to an understanding of general biological principles even though these methods cannot be used to study the normal cell cycle.  相似文献   

18.
Theories about the first Indo-European migration are numerous. Significant contribution in attempt to resolve these theories is given by analysing skeletal material from two biggest prehistoric archaeological sites from N-E Croatia. Eight skeletons of Starcevo culture from sites "Nama" and "Hotel" at Vinkovci (6100-5500 BC) and seven skeletons of Vucedol culture from the site Vineyard Streim at Vucedol near Vukovar (3000-2500 BC) were analysed. Methods of classical anthropological analysis tried to distinguish the differences among members of both populations, while the methods of molecular genetics were used in defining possible genetic structure of both ancient populations. Established differences speak on the behalf of the theory of Maria Gimbutas about the first Indo-European migration with a cattle breeding population from the east around 3500 BC.  相似文献   

19.
Under the condition of receptor blockade produced by continuous presence of an agonist in the organ bath, it was attempted to determine the dissociation constants for C-terminal partial sequences of the substance P at an isolated guinea pig ileum, by analogy with the method involving irreversible antagonists, and to compare them with the biological activity at the guinea pig ileum and the rat colon (ED50 values). Differentiation of the biological activity at the guinea pig ileum into affinity and "intrinsic efficacy" allows one to explain quantitative differences in determining the biological value on both isolated organs, and to reveal the contribution of the individual amino acids to affinity and "intrinsic efficacy".  相似文献   

20.
Ernst Mayr said that one of Darwin's greatest contributions was to show scholars the way to population thinking, and to help them discard a mindset of typological thinking. Population thinking rejects a focus on a central representative type, and emphasizes the variation among individuals. However, Mayr's choice of terms has led to confusion, particularly among biologists who study natural populations. Both population thinking and the concept of a biological population were inspired by Darwin, and from Darwin the chain for both concepts runs through Francis Galton who introduced the statistical usage of "population" that appears in Mayr's population thinking. It was Galton's "population" that was modified by geneticists and biometricians in the early 20th century to refer to an interbreeding and evolving community of organisms. Under this meaning, a population is a biological entity and so paradoxically population thinking, which emphasizes variation at the expense of dwelling on entities, is usually not about populations. Mayr did not address the potential for misunderstanding but for him the important part of the population concept was that the organisms within a population were variable, and so he probably thought there should not be confusion between population thinking and the concept of a population.  相似文献   

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