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1.
L. H. Bailey cited Mendel's 1865 and 1869 papers in the bibliography that accompanied his 1892 paper, Cross-Breeding and Hybridizing, and Mendel is mentioned once in the 1895 edition of Bailey's "Plant-Breeding." Bailey claimed to have copied his 1892 references to Mendel from Focke. It seems, however, that while he may have first encountered references to Mendel's work in Focke, he actually copied them from the Royal Society "Catalogue of Scientific Papers." Bailey also saw a reference to Mendel's 1865 paper in Jackson's "Guide to the Literature of Botany." Bailey's 1895 mention of Mendel occurs in a passage he translated from Focke's "Die Pflanzen-Mischlinge."  相似文献   

2.
This paper examines the contribution of the PhD dissertation of the American cytologist Michael F. Guyer (1874-1959) to the early establishment (in 1902-1903) of the parallel relationship between cytological chromosome behaviour in meiosis and Mendel's laws. Guyer's suggestions were among the first, which attempted to relate the variation observed in the offspring in hybridisation studies by a coherent cytological chromosome mechanism to meiosis before the rediscovery of Mendel's principles. This suggested for the first time that the chromosome mechanism involved a conjugation of maternal and paternal chromosomes during the synapsis followed by a segregation of parental chromosomes in the final germ cells and a random union of the final germ cells in the fertilization. It shows that this early suggestion was similar to William Austin Cannon's later chromosome proposal attempting to explain Mendel's principles and had some influence on Walter Sutton's cytological suggestion explaining correctly the behaviour of Mendel's particle by 1903.  相似文献   

3.

Background  

The present article corrects common textbook accounts of Mendel's experiments by re-establishing what he wrote and how he accounted for his observations. It notes the long-established tests for the validity of any explanations that purport to explain observations obtained by experiment. Application of these tests to Mendel's paper shows that the arguments he used to explain his observations were internally consistent but were, on one crucial issue, implausible. The same tests are applied to the currently accepted explanation for Mendel's observations.  相似文献   

4.
This paper is concerned with the role of rational belief change theory in the philosophical understanding of experimental error. Today, philosophers seek insight about error in the investigation of specific experiments, rather than in general theories. Nevertheless, rational belief change theory adds to our understanding of just such cases: R. A. Fisher's criticism of Mendel's experiments being a case in point. After an historical introduction, the main part of this paper investigates Fisher's paper from the point of view of rational belief change theory: what changes of belief about Mendel's experiment does Fisher go through and with what justification. It leads to surprising insights about what Fisher had done right and wrong, and, more generally, about the limits of statistical methods in detecting error.  相似文献   

5.
6.
The question posed by the title is usually answered by saying that the "synthesis" between the theory of evolution by natural selection and classical genetics, which took place in 1930s-40s, would have taken place much earlier if Darwin had been aware of Mendel and his work. What is more, it nearly happened: it would have been enough if Darwin had cut the pages of the offprint of Mendel's work that was in his library and read them! Or, if Mendel had come across Darwin in London or paid him a visit at his house in the outskirts! (on occasion of Mendel's trip in 1862 to that city). The aim of the present paper is to provide elements for quite a different answer, based on further historical evidence, especially on Mendel's works, some of which mention Darwins's studies.  相似文献   

7.
Abstract 1. The Alaskan swallowtail butterfly (Papilio machaon aliaska) uses three unrelated plant species as hosts: Cnidium cnidiifolium (Apiaceae), Artemisia arctica (Asteraceae), and Petasites frigidus (Asteraceae). The research presented here investigated whether there are any consistent patterns in host choice by P. m. aliaska females. 2. The first two experiments were designed to test if P. m. aliaska host preference is constant or if it changes from day to day. If host preference is labile, the experiments were designed to also test whether a female’s diet breadth narrows or expands over time. 3. The third experiment tested the host preferences of female offspring from several wild-caught P. m. aliaska females. If P. m. aliaska individuals are specialised in their host use, then all of the offspring from a single female would likely prefer the same host-plant species. This experiment was also designed to test the Hopkins’ host selection principle; does the food plant on which a female is reared as a larva influence her future choices when she is searching for host plants for her own offspring? 4. The results from all of these experiments indicate that P. m. aliaska females vary greatly in their oviposition behaviour and in their preferences for the three host plants. Most populations appear to consist of generalists with labile oviposition behaviour. There is no evidence to support the Hopkins’ host selection principle. 5. It is suggested that the generalised selection of host plants by P. m. aliaska females may be a ‘bet-hedging’ strategy and that this strategy may maximise reproductive fitness in an unpredictable environment.  相似文献   

8.
Presently the gold standard diagnostic technique for rabies is the direct immunofluorescence assay (dFA) which is very expensive and requires a high level of expertise. There is a need for more economical and user friendly tests, particularly for use in developing countries. We have established one such test called the direct rapid immunohistochemical test (dRIT) for diagnosis of rabies using brain tissue. The test is based on capture of rabies nucleoprotein (N) antigen in brain smears using a cocktail of biotinylated monoclonal antibodies specific for the N protein and color development by streptavidin peroxidase-amino ethyl carbazole and counter staining with haematoxollin. The test was done in parallel with standard FAT dFA using 400 brain samples from different animals and humans. The rabies virus N protein appears under light microscope as reddish brown particles against a light blue background. There was 100 % correlation between the results obtained by the two tests. Also, interpretation of results by dRIT was easier and only required a light microscope. To conclude, this newly developed dRIT technique promises to be a simple, cost effective diagnostic tool for rabies and will have applicability in field conditions prevalent in developing countries.  相似文献   

9.
Carl Correns (1864-1933) came to recognize Mendel's rules between 1894 and 1900 while trying to find out the mechanism of xenia, that is, the direct influence of the fertilizing pollen on the mother plant in maize and peas among other species. In this paper, I am concerned with the ten years of Correns' work after the annus mirabilis of 1900 until 1910, when the main outlines of the new science of genetics had been established. It is generally assumed that after 1900 Correns quickly began probing the limits of Mendelian inheritance, both as far as the explanatory force of formal transmission genetics and the generality of Mendel's laws are concerned. A careful examination of his papers however shows that he was much more interested in the scope of Mendelian inheritance than in its limits. Even his work with variegated Mirabilis plants, which historiographical folklore still presents as a result of Correns' growing interest in cytoplasmic inheritance, can be shown to have been conducted to corroborate just the opposite, namely, the validity of the nuclear paradigm. The paper will show that Correns' research results in those years (among them the Mendelian inheritance of sex in higher plants) were the outcome of a complex experimental program which involved breeding experiments with dozens of different species.  相似文献   

10.
In contemporary texts in biology and genetics, Mendel is frequently portrayed as a theorist who was the father of classical genetics. According to some authors, he created his theory of inheritance to explain the results of his experimental hybridizations of peas. Others have proposed that he designed and carried out his experiments to demonstrate the correctness of a theory of inheritance he had already developed. We disagree strongly with these views of Mendel. Instead, we have come to regard him as an empirical investigator trying to discover the empirical natural laws describing the formation of hybrid peas and the development of their offspring over several generations. We have supported our view with an analysis of portions of Mendel's paper and his letters to Carl N ageli.  相似文献   

11.
相对速率检验方法与实用程序   总被引:1,自引:0,他引:1  
相对速率检验是检验分子钟假设正确与否的一种有效工具。本文简要介绍了该方法的基本原理,提出了一种新的序列差异计算矩阵,并应用Visual Basic语言编制了一个相对速率检验程序。  相似文献   

12.
W W Piegorsch 《Biometrics》1990,46(4):915-924
R. A. Fisher is widely respected for his contributions to both statistics and genetics. For instance, his 1930 text on The Genetical Theory of Natural Selection remains a watershed contribution in that area. Fisher's subsequent research led him to study the work of (Johann) Gregor Mendel, the 19th century monk who first developed the basic principles of heredity with experiments on garden peas. In examining Mendel's original 1865 article, Fisher noted that the conformity between Mendel's reported and proposed (theoretical) ratios of segregating individuals was unusually good, "too good" perhaps. The resulting controversy as to whether Mendel "cooked" his data for presentation has continued to the current day. This review highlights Fisher's most salient points as regards Mendel's "too good" fit, within the context of Fisher's extensive contributions to the development of genetical and evolutionary theory.  相似文献   

13.
Punnett's square     
The origin and development of Punnett's Square for the enumeration and display of genotypes arising in a cross in Mendelian genetics is described. Due to R. C. Punnett, the idea evolved through the work of the 'Cambridge geneticists', including Punnett's colleagues William Bateson, E. R. Saunders and R. H. Lock, soon after the rediscovery of Mendel's paper in 1900. These geneticists were thoroughly familiar with Mendel's paper, which itself contained a similar square diagram. A previously-unpublished three-factor diagram by Sir Francis Galton existing in the Bateson correspondence in Cambridge University Library is then described. Finally the connection between Punnett's Square and Venn Diagrams is emphasized, and it is pointed out that Punnett, Lock and John Venn overlapped as Fellows of Gonville and Caius College, Cambridge. Copious illustrations are given.  相似文献   

14.
稻鸭共作对稻田水体环境的影响   总被引:13,自引:0,他引:13  
通过田间对比试验,研究了稻鸭共作技术对稻田水体环境性质的影响.结果表明:稻鸭共作能够降低稻田表层水体的温度与pH值,提高电导率、氧化还原电位、混浊度和总氮、总磷、总钾三大营养元素的含量,其中总氮、总磷、总钾的含量分别比常规稻作增加1.85~5.06倍、2.01~8.70倍和42.79%~109.18%.说明稻鸭共作对改善水体理化性质、提高有效肥力供应,进而优化稻田生态环境和促进水稻的生长发育均具有积极作用.  相似文献   

15.
In this paper, we discuss briefly three of the several lines of evidence that we believe demonstrate de Vries's lack of understanding of Mendel's paper. In our view, at least part of de Vries's failure of understanding derives from the fact that he appears to have viewed Mendel's paper as being mainly about the inheritance of characters that was his own interest. Therefore, he looked at it to see whether Mendel had found any laws of inheritance. Mendel had done his research for another purpose, to find the laws describing the formation of hybrids and the development of their offspring. Thus, de Vries started his examination of Mendel's paper with a very fundamental misunderstanding of what it was about.  相似文献   

16.
以位于湖南省新化和宁乡县两个稻田肥力长期定位试验点的土样为材料,研究了不同施肥处理对稻田土壤有机氮组分、微生物生物量及功能多样性的影响.结果表明:与不施肥处理(CK)相比,化肥配施有机肥处理提高了稻田土壤酸解总氮(TAHN)及其组分中氨基糖氮(ASN)、氨基酸氮(AAN)和酸解氨态氮(AN)的含量,不同施肥处理对组分中酸解未知氮(HUN)的影响不尽相同.与CK相比,单施化肥处理对土壤微生物生物量碳、氮(MBC、MBN)含量的影响较小,化肥配施有机肥处理则显著提高了土壤MBC和MBN的含量.采用BIOLOG法对土壤微生物群落功能多样性进行测定,结果表明:中、高量有机肥处理提高了稻田土壤微生物的碳源利用率和微生物群落功能多样性;土壤微生物碳源利用的类型因长期不同施肥处理而产生差异.  相似文献   

17.
In this paper I explore the historical context in which news of the rediscovery of Mendel's laws was received in England. This exploration leads me to the Cambridge zoologist, William Bateson, to his exploitation of the prestige and support of the Royal Horticultural Society, and to his interaction with certain of the leading horticultural tradesmen prominent in that society. I argue that the policy of the RHS in the 1890s to promote hybridisation rather than plant collecting was of crucial importance in bringing about a productive symbiosis between Bateson and his circle and the horticultural community. I look for parallels between the aims of the horticulturists and the character of the Mendelian programme as it is represented in Bateson's foundational text: Mendel's Principles of Heredity (1909).  相似文献   

18.
目的:探讨临床常规生化检验结果的影响因素,并提出相应的预防对策。方法:回顾性分析2012年2月~2013年2月我院检验科进行的生化常规检测10256例次的检查结果,采用美国BIORAD公司生化定值多项3水平质控品于检测前、中、后进行质控分析,对产生偏差的原因按实验前、实验中、实验后进行归类总结。结果:84例经复核出现超过10%以上偏差,占总分析例数的0.82%。实验前不良事件是产生实验结果偏差的主要因素,占总体产生偏差例数的78.57%,其中患者因素与标本处理不当构成了实验前干扰因素的主体,分别占实验前因素的39.39%和36.36%。不明原因溶血与标本采集方法不当也是实验前的实验干扰因素。实验中影响检测结果的因素主要为仪器故障、试剂过期和失效、定标品或定标曲线过期,分别占实验中因素的46.67%、33.33%、20%。实验后干扰因素均为审核不及时或不细致导致的检测报告不合格。结论:在进行临床常规生化检查的过程中,任何一个环节出现失误均有可能对检查结果造成影响,特别是患者因素、标本采集方法不当及处理不当,均应该引起医护人员的重视。  相似文献   

19.
小麦叶片色素含量的高光谱监测   总被引:10,自引:0,他引:10  
连续两年采用不同小麦品种在不同施氮水平下进行大田试验,建立了小麦叶片色素含量的光谱定量监测模型.结果表明,叶片色素含量随着施氮水平的增加而提高,品种间存在差异,叶绿素(Chl) a+b相对含量随生育时期的变化较Chl b和类胡萝卜素(Car)更为明显.群体叶片色素含量的敏感波段主要存在于可见光区,其中,红边区域表现显著.红边位置参数REPLE和REPIG与叶绿素关系较为密切,REPLE的表现较好.以REPLE为变量对Chl a、Chl b和Chl a+b进行方程拟合,决定系数R2分别为0.835、0.841和0.840;对Car含量进行方程拟合,其R2显著下降,且光谱参数间差异较小.经独立数据的检验表明,红边位置的估算结果较好,以REPIG为变量对Chl b进行预测,模型测试的R2和RE分别为0.632和18.2%;以REPLE为变量对Chl a、Chl a+b和Car含量进行预测,R2分别为0.805、0.744和0.588,RE分别为9.0%、9.7%和14.6%.表明红边位置与叶片色素含量关系密切且表现稳定,利用REPLE可以对小麦叶片Chl a和Chl a+b含量进行可靠的监测.  相似文献   

20.
The micronucleus test has been widely used as an in vivo cytogenetic test. It employs two different kinds of supravital staining methods which use either new methylene blue (N) and Giemsa (G) or acridine orange (AO). We have developed a new staining procedure for the preparation of specimens supravitally stained with possible long-term storage, using both N and AO. This N/AO-staining method involves three steps; (1) combination of the target tissue or target cells with an equivalent volume of 0.5% solution of new methylene blue (N-staining step), (2) immediate smear of the mixture, followed by treatment with methanol for 10 min for fixation and removal of N and drying (referred to as fixed-decolorized specimens), and (3) staining with 0.007% solution of AO for 3 min, followed by washing with Sörensen's buffer (pH 6.8) and covering of specimens before observation (AO-staining step). To examine whether the N/AO-staining method is useful for the micronucleus test, comparisons were made between N-, N/AO-, and AO-stained specimens prepared supravitally from peripheral blood of rats with and without treatment of cyclophosphamide. The results indicate that N/AO-stained specimens can be supravitally observed after long-term storage with the same coloration and comparable frequencies of micronucleated reticulocytes with a positive response as AO-stained specimens, if the staining process is temporarily stopped before AO-staining (as fixed-decolorized specimens), or if the AO-staining step is repeated. The results also showed that separated reticulocyte types are supravitally stained in a similar fashion to N-stained specimens but not to AO-stained specimens, indicative of the preservation of the supravital feature of N-staining. Taken together these results suggest that the N/AO-staining procedure could offer an additional useful staining tool for the micronucleus test.  相似文献   

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