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1.
In what follows, I consider the role of analogy in the first edition of Darwin’s Origin. I argue that Darwin follows Herschel’s methodology and hence exploits an analogy between artificial and natural selection that allows him generalize selection as a cause of evolutionary change. This argument strategy is not equivalent to an argument from analogy. Reading Darwin’s argument as conforming to Herschel’s two-step methodology of causal analysis followed by generalization allows us to understand the role and placement of Darwin’s discussion of artificial selection in the Origin, without making the mistake of portraying Darwin’s argument for the existence and character of natural selection as an analogical argument.  相似文献   

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Julian Huxley’s (1887–1975) contribution to twentieth-century biology and science popularisation is well documented. What has not been appreciated so far is that despite Huxley’s eminence as a public scientific figure and the part that he played in the rise of experimental zoology in Britain in the 1920s, his own research was often heavily criticised in this period by his colleagues. This resulted in numerous difficulties in getting his scientific research published in the early 1920s. At this time, Huxley started his popular science career. Huxley’s friends criticised him for engaging in this actively and attributed the publication difficulties to the time that he allocated to popular science. The cause might also have its roots in his self-professed inability to delve deeply into the particularities of research. This affected Huxley’s standing in the scientific community and seems to have contributed to the fact that Huxley failed twice in the late 1920s to be elected to the Royal Society. This picture undermines to some extent Peter J. Bowler’s recent portrayal of Huxley as a science populariser.  相似文献   

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We investigated the feasibility of using driver’s license records to obtain height and weight data of individuals. First, we linked Washington State driver’s license records (DOL) to the state birth files to assess how well driver’s licenses can be linked to a public health database. We were able to match 78.4% of mothers and 71.7% of fathers on birth records to driver’s license records. Then we assessed the accuracy of DOL height and weight data by comparing them to heights and weights measured on control women enrolled in a cancer etiology study (CES). There is a close relation between CES and DOL heights, but not a close relation between weights. Our results suggest that driver’s license files are a good source of information for women’s heights, but are not as good for women’s weights.  相似文献   

6.
Romantic Naturphilosophie has been at the centre of almost every account of early nineteenth-century sciences, be it as an obstacle or as an aid for scientific advancement. The following paper suggests a change of perspective. I seek to read Naturphilosophie as one manifestation among others of a more general concern with the question of how experience enables the subject to acquire knowledge about objects. To illustrate such an approach, I focus on Johannes Müller’s early work. Here one finds two contrasting images of microscopical observation, its set-up, and the observer: the embryological study of 1830 demands a ‘philosophical grasp’ of the appearances. In contrast, the investigations of blood of 1832 are presented as a series of controlled experiments. I argue that an interpretation of this contrast in terms of an appropriation and casting aside of Naturphilosophie is not altogether convincing. Instead, both images of microscopy are manifestations of a more general problem, namely, the problem of exactly how subject and object came together in experience. I show how this concern not only shaped the methodological sensibilities particular to Müller’s embryology and the investigation of bodily liquids but also provided the epistemological principles and the target for his sense-physiological experiments. It bound Müller’s work together with Naturphilosophie and linked Naturphilosophie with other contemporaneous projects in philosophy. All of these enterprises sought to contribute to ongoing debates about how experience allowed the subject to acquire knowledge about the world.  相似文献   

7.
Metapopulation extinction risk is the probability that all local populations are simultaneously extinct during a fixed time frame. Dispersal may reduce a metapopulation’s extinction risk by raising its average per-capita growth rate. By contrast, dispersal may raise a metapopulation’s extinction risk by reducing its average population density. Which effect prevails is controlled by habitat fragmentation. Dispersal in mildly fragmented habitat reduces a metapopulation’s extinction risk by raising its average per-capita growth rate without causing any appreciable drop in its average population density. By contrast, dispersal in severely fragmented habitat raises a metapopulation’s extinction risk because the rise in its average per-capita growth rate is more than offset by the decline in its average population density. The metapopulation model used here shows several other interesting phenomena. Dispersal in sufficiently fragmented habitat reduces a metapopulation’s extinction risk to that of a constant environment. Dispersal between habitat fragments reduces a metapopulation’s extinction risk insofar as local environments are asynchronous. Grouped dispersal raises the effective habitat fragmentation level. Dispersal search barriers raise metapopulation extinction risk. Nonuniform dispersal may reduce the effective fraction of suitable habitat fragments below the extinction threshold. Nonuniform dispersal may make demographic stochasticity a more potent metapopulation extinction force than environmental stochasticity.  相似文献   

8.
Entropy-related biodiversity indices deriving their conceptual basis from Shannon’s information theory have a long history of use in ecology for quantifying community structure and diversity. In addition, in the last two decades, numerous information–theoretical indices, such as the landscape dominance index, have been extensively applied to characterize landscape diversity in space and time. In this contribution, we offer a simple analytical relation between Pielou’s evenness J and landscape dominance D within the broader context of Hill’s parametric diversity family. Within this context, we recommend the use of Hill’s diversity number evenness E1,0 to overcome the shortcomings both of Pielou’s evenness J and the landscape dominance index D.  相似文献   

9.
The purpose of the study was (1) to assess changes in electromyographical (EMG) and mechanomyographical (MMG) signals of the biceps and triceps brachii muscles during absolute submaximal load holding in Parkinson’s disease patients tested during their medication “ON-phase” and in age-matched controls, and (2) to check whether mechanomyography can be useful in evaluation of neuromuscular system activity in Parkinson’s disease patients.The data analysis was performed on nine females with Parkinson’s disease and six healthy, age-matched females. The EMG and MMG signals were recorded from the short head of the biceps brachii (BB) and the lateral head of the triceps brachii (TB) muscles.It was concluded that compared to the controls, the Parkinson’s disease patients exhibited higher amplitude in the biceps brachii muscle and lower median frequency of the MMG signal in the both tested muscles. However, no differences in the EMG amplitude and an increase of the EMG median frequency in the triceps brachii muscle of the Parkinson’s disease group were observed. The MMG was not affected by physiological postural tremor and can depict differences between parkinsonians and controls, which may suggest that it is valuable tool for neuromuscular assessment for this condition.  相似文献   

10.
This paper traces the historical origins of Friedrich A. Hayek’s theory of cultural evolution, and argues that Hayek’s evolutionary thought was significantly inspired by Alexander M. Carr-Saunders and Oxford zoology. While traditional Hayek scholarship emphasizes the influence of Carl Menger and the British eighteenth-century moral philosophers, I claim that these sources underdetermine what was most characteristic of Hayek’s theory, viz. the idea that cultural evolution is a matter of group selection, and the idea that natural selection operates on acquired as well as on inherited properties.  相似文献   

11.
The Italian geologist Giambattista Brocchi (1771–1826) is presented as a key figure in the historical period preceding young Charles Darwin’s first work on transmutational theory while on the Beagle. The brief biographical account focuses on Brocchi’s writings related to his analogy that species have births and deaths like individuals, and culminates in his most important work, Subapennine Fossil Conchology of 1814. Brocchi’s analogy as an original and fertile way to approach the fossil record was to influence Darwin’s first evolutionary thinking. Relevant passages of the book are presented for the first time in an English translation.  相似文献   

12.
Fractionation of distiller’s grains into value added products may serve to improve the economic viability of dry grind corn ethanol facilities in the wake of variable corn and ethanol prices. This research is aimed at creating a high protein, high lysine product from the grain using alkaline protein extractions in conjunction with hydrolysis of the remaining fiber to sugars which are then fermented to ethanol. Alkaline extractions improved the lysine content in protein products, although protein solubility did not exceed 45% of the total protein. In addition, oligomeric carbohydrates, starch, and other water solubles were also extracted, leading to a low purity protein product. Resulting sugar yields following ammonia fiber expansion (AFEX) pretreatment were also lower for extracted distiller’s grains. From these experiments, it does not appear likely that alkaline extraction is a useful tool for fractionation of distiller’s grains. However, pretreatment and hydrolysis can be an effective tool for further fractionation of protein.  相似文献   

13.
The analogy between artificial selection of domestic varieties and natural selection in nature was a vital element of Darwin’s argument in his Origin of Species. Ever since, the image of breeders creating new varieties by artificial selection has served as a convincing illustration of how the theory works. In this paper I argue that we need to reconsider our understanding of Darwin’s analogy. Contrary to what is often assumed, nineteenth-century animal breeding practices constituted a highly controversial field that was fraught with difficulties. It was only with considerable effort that Darwin forged his analogy, and he only succeeded by downplaying the importance of two other breeding techniques – crossing of varieties and inbreeding – that many breeders deemed essential to obtain new varieties. Part of the explanation for Darwin’s gloss on breeding practices, I shall argue, was that the methods of his main informants, the breeders of fancy pigeons, were not representative of what went on in the breeding world at large. Darwin seems to have been eager to take the pigeon fanciers at their word, however, as it was only their methods that provided him with the perfect analogy with natural selection. Thus while his studies of domestic varieties were important for the development of the concept of natural selection, the reverse was also true: Darwin’s comprehension of breeding practices was moulded by his understanding of the working of natural selection in nature. Historical studies of domestic breeding practices in the eighteenth and nineteenth century confirm that, besides selection, the techniques of inbreeding and crossing were much more important than Darwin’s interpretation allowed for. And they still are today. This calls for a reconsideration of the pedagogic use of Darwin’s analogy too.  相似文献   

14.
This paper examines how in the ‘Critique of teleological judgment’ Kant characterized the concept of natural purpose in relation to and in distinction from the concepts of nature and the concept of purpose he had developed in his other critical writings. Kant maintained that neither the principles of mechanical science nor the pure concepts of the understanding through which we determine experience in general provide adequate conceptualizations of the unique capacities of organisms. He also held that although the concept of natural purpose was derived through reflection upon an analogy to human purposive activity in artistic production and moral action, it articulates a unique notion of intrinsic purposiveness. Kant restricted his critical reflections on organisms to phenomena that can be given to us in experience, criticizing speculations on their first origins or final purpose. But I argue that he held that the concept of natural purpose is a product of the reflecting power of judgment, rather than an empirical concept, and represents only the relation of things to our power of judgment. Yet it is necessary for the identification of organisms as organized and self-organizing, and as subject to unique norms and causal relations between parts and whole.  相似文献   

15.
Some early nineteenth-century American naturalists condemned their contemporary, Constantine Samuel Rafinesque (1783–1840), as ‘eccentric’, or worse. Both during his life and long after his death, his botanical work in particular was criticised, even ridiculed. However, in recent years, attempts have been made to restore his reputation and the term ‘genius’ has even been used to describe him. This paper examines this continuing fascination with this strange, disturbing figure and argues that in the competing interpretations of his life and work, Rafinesque has generally been used to typify bad classification; he is perhaps better understood in a broader, literary context as embodying a particular kind of American national identity.  相似文献   

16.
We present a further, yet important, step in applying Catania Mouse Model & simulator (SimTriplex) of immune system response to vaccination. In particular we show that, as immune response can induce toxicity, one can calibrate the vaccine administrations in such a way to avoid toxicity effects, keeping immunoprevention from cancer. This result increases the model’s potential applications.  相似文献   

17.
During his historic Galápagos visit in 1835, Darwin spent nine days making scientific observations and collecting specimens on Santiago (James Island). In the course of this visit, Darwin ascended twice to the Santiago highlands. There, near springs located close to the island’s summit, he conducted his most detailed observations of Galápagos tortoises. The precise location of these springs, which has not previously been established, is here identified using Darwin’s own writings, satellite maps, and GPS technology. Photographic evidence from excursions to the areas where Darwin climbed, including repeat photography over a period of four decades, offers striking evidence of the deleterious impact of feral mammals introduced after Darwin’s visit. Exploring the impact that Darwin’s Santiago visit had on his thinking – especially focusing on his activities in the highlands – raises intriguing questions about the depth of his understanding of the evolutionary evidence he encountered while in the Galápagos. These questions and related insights provide further evidence concerning the timing of Darwin’s conversion to the theory of evolution, which, despite recent claims to the contrary, occurred only after his return to England.  相似文献   

18.
Reliability is one of the most important aspects of the behaviour observations measuring personality traits in animals. The most fundamental way to test reliability is the assessment of the test–retest consistency. On the other hand, in situations where social interaction between a human participant and the animal subject is at the scope of the study, the behaviour of the humans in the test situation should be restricted by a set of rules. However, if more than one experimenter participates in the observations, the similarity of the behaviour of different persons is an important aspect of the reliability of the study.In our first study we investigated the consistency of dogs’ behaviour during approach by a person in a friendly and in a threatening way, repeating the test either immediately after the first test or at least 6 months later. We found that the dogs’ sensitivity to the human's behavioural cues in this situation proved to be consistent over repetition when the second test was performed approximately 1 year after the first test, but it was not the case when the time elapsed between test occasions was a few seconds. The detailed analysis indicated that dogs performing extreme behaviour (friendly or threatening) tended to show more conservative responses than dogs showing intermediate reactions when the stranger approached threateningly. Nonetheless, the reaction of the dogs failed to be in accordance with the opinion of the owners about the dogs’ behaviour in similar situations in everyday life.In the second study we examined the consistency of the dogs’ behaviour in the same situation when confronted with two different unfamiliar persons immediately after each other. The consistency of the dogs’ response to the two experimenters was found to be reliably high.In sum, this test procedure proved to be reliable enough to be a valuable measure of a definite part of the personality characters of dogs.  相似文献   

19.
The enantioselective reduction of cinnamaldehyde derivatives is an attractive strategy to prepare various optically active multifunctional molecules that can be used as chiral building blocks for the synthesis of some HIV-protease inhibitors. The asymmetric reduction with pH adjusted to 5.5 of α-substituted-cinnamaldehydes (Br, N3) mediated by baker’s yeast (Saccharomyces cerevisiae) yielded α-substituted-3-phenyl-1-propanol in excellent enantiomeric excesses and yields.  相似文献   

20.
Charles Darwin is well known for his studies on the expression of emotions in animals and humans and as founding father of the concept of sexual selection. Yet it is commonly believed that the various arguments Darwin developed about behavior were usually illustrated only by anecdotes and observations recounted by explorers, naturalists, or zookeepers, and lacking any experimental approach. Here we show that this is not true. In his last book, The Formation of Vegetable Mould Through the Action of Worms (1881), Darwin mentions a series of meticulous experiments he ran to test his hypotheses about why earthworms plug their burrows and comes to the conclusion that earthworms seem to act in an intelligent way. His study can still function as a prime example of how to design an experiment for testing hypotheses. Only one part was missing in Darwin’s research: statistical analyses. We retrieved his data and analyzed them statistically. Based on these results, we cannot reject his conclusion as the statistical analyses confirmed Darwin was right. This shows that Charles Darwin already used a hypothetico-deductive approach, and he can thus be seen as the first true behavioral ecologist—a representative of a discipline that has been recognized for only about a hundred years.  相似文献   

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