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1.
Linnaeus' timely work was a major contribution to botany and is of interest to students of botany at all levels. This is a brief biographical outline with a version of his Flora's Clock which some might like to try.  相似文献   

2.
Noël Bernard, the famous discoverer of the symbiotic germination of orchid seeds, died a one hundred years ago in 1911, at the age of 37. Here we remember his life, personality, training and contributions to science. He studied at the Ecole Normale Supérieure and took courses on microbiology at the Pasteur institute. He was also an admirer of Darwin. We briefly summarize some of his inspiring research in botany, plant physiology and symbiosis, especially that on orchid seed germination and tuber formation, published over a period of only 12 years. We briefly consider his legacy and the research that has recently been published in Symbiosis, which extends the various fields of research that Noël Bernard pioneered.  相似文献   

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Charles Darwin's work with orchids and his thoughts about them are of great interest and not a little pride for those who are interested in these plants, but they are generally less well known than some of his other studies and ideas. Much has been published on what led to his other books and views. However, there is a paucity of information in the general literature on how Darwin's orchid book came about. This review will describe how The Various Contrivances by Which Orchids Are Fertilised by Insects came into being and will discuss the taxonomy of the orchids he studied. It also will concentrate on some of the less well-known aspects of Darwin's work and observations on orchids-namely, rostellum, seeds and their germination, pollination effects, and resupination-and their influence on subsequent investigators, plant physiology, and orchid science.  相似文献   

5.
Over years of friendly meetings with Professor Aharon Katzir-Katchalsky, many topics of mutual interest were discussed. He was the ideal person to come to with a problem. After being subjected to his critical, analytic mind, most research problems seemed simple, more clearly defined and understandable. His broad biologic and scientific background grew from an apparently insatiable interest in all natural phenomena. He generously shared his knowledge and imparted his wisdom with a share of his own infectious excitement. He was quick to sense the significance of understanding of biological processes to their practical application. For this reason it seems appropriate to relate the progress made in the understanding of cell volume regulation, which had been discussed on several occasions with him, to its possible significance as a factor in disease processes.Dr. Frega is a Fellow of the National Kidney Foundation, Inc., 1972–73.  相似文献   

6.
This paper examines Charles Darwin's idea that language-use and humanity's unique cognitive abilities reinforced each other's evolutionary emergence-an idea Darwin sketched in his early notebooks, set forth in his Descent of man (1871), and qualified in Descent's second (1874) edition. Darwin understood this coevolution process in essentially Lockean terms, based on John Locke's hints about the way language shapes thinking itself. Ironically, the linguist Friedrich Max Müller attacked Darwin's human descent theory by invoking a similar thesis, the German romantic notion of an identity between language and thought. Although Darwin avoided outright contradiction, when he came to defend himself against Müller's attacks, he undercut some of his own argumentation in favor of the coevolution idea. That is, he found it difficult to counter Müller's argument while also making a case for coevolution. Darwin's efforts in this area were further complicated by British and American writers who held a naturalistic view of speech origins yet still taught that language had been invented by fully evolved homo sapiens, thus denying coevolution.  相似文献   

7.
This paper gives a detailed analysis of four seed lists in the journals of John Locke. These lists provide a window into a fascinating open network of botanical exchange in the early 1680s which included two of the leading botanists of the day, Pierre Magnol of Montpellier and Jacob Bobart the Younger of Oxford. The provenance and significance of the lists are assessed in relation to the relevant extant herbaria and plant catalogues from the period. The lists and associated correspondence provide the main evidence for Locke’s own important, though modest contribution to early modern botany, a contribution which he would have regarded as a small part of the broader project of constructing a natural history of plants. They also provide a detailed case study of the sort of open and informal network of knowledge exchange in the early modern period that is widely recognised by historians of science, but all too rarely illustrated.  相似文献   

8.
Mrs. Phelps was influenced by her older sister Emma Willard, a well known educational reformer, and by Amos Eaton, who helped form her botanical and scientific understanding. Feeling the lack of a suitable botanical textbook particularly for female students who were becoming more prevalant, she wrote, Familiar Lectures on Botany, published in 1829, using her first husband's surname (Lincoln). It quickly became popular and continued to be revised and reprinted through 1869. In 1833, a second botany text for lower level students, Botany for Beginners, appeared. It too, went through many reprintings up to 1891. Mrs. Phelps’ other books and writings on science and education were popular also. The botanical texts were educationally innovative in starting with flower structure using common living examples and integrating morphological and physiological aspects of plants. The Linnaean System was used to classify the “most common native and foreign” plants that were described mainly from Eaton's manuals. Clear figures, often copied from well-known authorities helped to instruct teachers and students. Because of its wide usage, even in later years in competition with the widely used textbooks of Asa Gray and Alphonso Wood, Mrs. Phelps’ books were an important factor in educating many students, especially females, in botany and inducing some of them to have a life-long interest in the science and in teaching it to others. She was, through her writings, a person who helped provide a favorable climate for the developing profession of botany in America.  相似文献   

9.
In 1992, in a special paper in the American Journal of Botany, Ernst Mayr attempted to ‘prove’ the biological species concept (BSC) worked as well in plants as it did in animals by analyzing the flora of the Concord region of northern Massachusetts. He concluded that there were minimal difficulties when applying the BSC for the plants of this particular area, and concluded that botanists were misguided in not accepting the BSC. He suggested that what he called ‘typological’ thinking was prevalent in the taxonomic community, and that this was a factor in botanical resistance to the BSC. Typology, as defined by Mayr in his 1992 foray into botany, is to a certain extent a straw‐man and, by the late 20th Century, no longer a way of thinking in widespread use in the taxonomic community in any organismal group. Here, I examine his analysis in the light of current interest in plant diversity. Species can be characterized as hypotheses about the distribution of variation in nature, subject to test with new data of many kinds. Species concepts like the BSC, although of interest philosophically and to researchers looking at mechanisms of speciation, may actually get in the way of achieving a baseline understanding of the diversity of life on Earth. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95 , 17–25.  相似文献   

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Triaperturate pollen in the monocotyledons: configurations and conjectures   总被引:2,自引:0,他引:2  
Triaperturate pollen are known in at least twenty seven genera of monocotyledons. Differences between aperture type and polarity indicate that the development of three apertures has occurred a number of times. Mode of cytokinesis during microsporogenesis is compared with differences in aperture configuration, to assess the extent to which this appears to influence aperture arrangement. Triapertury in monocot pollen tends to fall into one or another of three situations: 1) it is the normal state, 2) it is fairly common, but pollen with more or less apertures also occur in the taxon or sample, 3) it is a rare, or abnormal state for pollen which usually has less than three apertures. The various forms of triaperturate pollen are described, as well as monosulcate pollen of the orchid genera Cypripedium and Paphiopedilum, often misinterpreted as tri-sulcate, and the unusual extended trichotomosulcate pollen of Agrostocrinum (Hemerocallidaceae). Monosulcy, trichotomosulcy, and zonasulcy, with unusual and rare exceptions of zonasulcy in the eudicots, are aperture states shared exclusively with the basal dicots. Furthermore, to some extent all have links with the triaperturate condition in monocots and basal dicotyledons. This is discussed, as well as the association of tripory with polypory in monocots and basal dicots. The fossil pollen record is considered.This paper is dedicated to Klaus Kubitzki in recognition, not only for his extensive contribution to systematic botany, but also for his firm belief that pollen characteristics contribute to a better understanding of plant systematics and evolution.  相似文献   

13.
This is an historical paper examining the scientific background of George Ledyard Stebbins, Jr. (b. 1906), one of the foremost botanists of this century and one of the architects of the evolutionary synthesis, the intellectual event that brought together genetics and selection theory in the interval between 1920 and 1950. It considers his scientific influence and research, beginning with his Harvard education in 1924 and ending in 1950 with the publication of his book Variation and Evolution in Plants. The paper also more broadly assesses the contributions of other botanists to the evolutionary synthesis, including discussion of the work of Edgar Anderson (1897-1967) and others. It also traces the larger historical patterns of American botany, which saw a shift from East Coast botany as exemplified by Harvard botany, to West Coast botany, as exemplified by California botany.  相似文献   

14.
Synopsis Bill Ricker’s career went through many twists in his academic years. He had taken botany in his senior matriculation year at high school and he had collected over 100 species of flora before commencement of university life. At the conclusion of his first university year, he set out over the summer to collect a much larger sample of species, primarily from the Great Lakes-St. Lawrence ecoregion, to fulfil a requirement for a second year botany course (spermatophytes). He identified about 390 species, and some 254 were collected and pooled with those from previous years to make a final submission of 354 spermatophyte species. Field plant identification continued in each academic year thereafter, in concert with collections and identifications of aquatic invertebrates in his summer projects while under the employment of the Ontario Fisheries Research Laboratory. At the conclusion of his undergraduate years, Bill had taken more courses in botany than in zoology, and it was the summer employment that had really prepared him for postgraduate work in fisheries biology, which was ecologically oriented. When Bill left Ontario in the autumn of 1931 he had identified over 600 species of plants, excluding lower cryptogams, but including many aquatic species of higher plants. In western North America Bill’s botanical career began at Cultus Lake in 1931. He again studied all aspects of the basin while employed with the federal government, and from the work he assembled a Ph.D. thesis. At the time of thesis completion he had identified over 300 species of flora, including alpine plants at timberline, 1500 – 1800 m above lake level, and planktonic algae in its water column. In 1939, after more field fisheries work in the Fraser River basin of British Columbia, Bill accepted a position with the biological staff at Indiana University. In this period which concluded in 1950 he identified another 50 – 110 species of flora, all in the Carolinian ecoregion, and hitherto not seen by him. Considering all floral classes, Bill’s eastern North American repertoire had by then added up to 791 species, representative of more than 112 families of plants. Returning west for the remainder of his life, new identifications elsewhere added to his Cultus Lake list which slowly added up to about 1000 species for the west coastal region of North America. Flora was also identified elsewhere in the mid-continental region of North America, in Eurasia where the Abisko region of Lappland was a highlight, and in South America and New Zealand. Records of his botanical prowess, were kept primarily in his diaries, which began in 1923 and were maintained consistently to the end of 1934, and thereafter intermittently to 1949. The diaries reveal that his career as a budding botanist was subtly hijacked by a wily Professor W.H.K. Harkness in the rival Biology Department who out-manoeuvred Drs. R.B. Thompson and R.A. Sifton in the Botany Department. The former always managed to employ Bill in summer and keep him occupied in the department’s labs during the autumn and winter and spring, tying up any free time when the botanist had approached him on lab work. Certainly, the botany courses taken and which he excelled at were more appropriate for his aquatic ecological pursuits. Salesmanship won the day for the zoologists, but Bill was a life-long botanist regardless of whatever else he studied or managed throughout his professional career. The last days of his life had a botanical conclusion.  相似文献   

15.
Summary

Robert Smith (1874–1900) is credited with having made the first systematic ecological studies to be carried out in Britain. His childhood in Dundee is described and consideration is given to the possible influence of his brother William and of the countryside of Angus and Ayrshire in forming his early interest in field botany and vegetation science. His pioneering studies were encouraged by Patrick Geddes and D'Arcy Thompson, and later by Charles Flahault in Montpellier, so that Smith became an outstanding teacher and researcher at a time of momentous developments in the natural sciences.  相似文献   

16.
Of all substances threatening life in the seas, oil has received by far the most attention from the public, administrators, politicians and scientists. The main reasons for this are: (1) even limited amounts of oil are easily visible; (2) oil can exert obvious negative effects, e. g. extensive damage to birds and other animals, impairment of the recreational value of beaches and marinas, losses in fisheries due to tainting of catches and rejection by the public of seafood from areas known to have been recently polluted. In addition, dramatic tanker accidents are widely publicized. During the last decade tens of thousands of papers have been published about the impact of oil on the marine environment, and we are well informed about most basic facts, such as input and fate of oil, toxicity to adult organisms and recolonization. Due to considerable sophistication of analytical techniques, especially the introduction of glass-capillary gas chromatography, we are well aware that recently formed biogenic hydrocarbons by far extend the input directly due to pollution. Large gaps exist in our knowledge about sedimentation and transport of weathered oil, natural degradation rates, and the flow of hydrocarbons through the food web. Relatively little is known about the influence of oil and dispersants upon complex ecosystems. The often mentioned suspicion of increased cancer probability in humans due to seafood contaminated by hydrocarbons has not been substantiated; in fact, it seems unlikely that such an effect exists. By far the greatest uncertainty about potential oil impact concerns possible negative effects of hydrocarbons on chemical communication mechanisms between organisms. Intensive studies of behaviour scientists working with concentrations far below the toxic level are needed in fisheries biology, zoology and botany. Most cases of oil contamination known thus far have been limited in space and time; the oil has turned out to be degradable by natural processes. Such oil pollution neither endangers nor considerably impairs the future of mankind. In future research, more than anything else, objective critical evaluation and careful quantification are needed. Dedicated to Dr. C. E. ZoBell, Professor emeritus Scripps Institution of Oceanography on the occasion of his 75th birthday in recognition of his fundamental and outstanding contributions to marine microbiology and to our understanding of the role played by oil-degrading bacteria  相似文献   

17.
Professor Nobuhiko Katunuma is well known for his outstanding contribution to the understanding of proteolysis in general and cysteine proteinases and their inhibitors in mammals. In fact, he is a world pioneer in the field. In 1963, he started his highly successful scientific career as a Professor at the Institute for Enzyme Research, the University of Tokushima. During the initial 30 years of his career, he was interested in vitamin B6 metabolism and discovered the acceleration of turnover rates of pyridoxal enzyme in apoprotein formation. After this period, his interest expanded to lysosomal cystein proteinases and their endogenous inhibitors. After determining the crystal structure of human cathepsin B, he generated a series of chemically synthesized specific inhibitors of cathepsins. These inhibitors are currently used throughout the world and some of them have been applied therapeutically in various diseases. During his career and even at present, Professor Katunuma has been studying Biochemistry in Medicine and also practicing to become a 'Kendo sword fencing Fighter'.  相似文献   

18.
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   

19.
The Australian scientist Frank Macfarlane Burnet-winner of the Nobel Prize in 1960 for his contributions to the understanding of immunological tolerance-is perhaps best recognized as one of the formulators of the clonal selection theory of antibody production, widely regarded as the 'central dogma' of modern immunology. His work in studies in animal virology, particularly the influenza virus, and rickettsial diseases is also well known. Somewhat less known and publicized is Burnet's research on bacteriophages, which he conducted in the first decade of his research career, immediately after completing medical school. For his part, Burnet made valuable contributions to the understanding of the nature of bacteriophages, a matter of considerable debate at the time he began his work. Reciprocally, it was while working on the phages that Burnet developed the scientific styles, the habits of mind and laboratory techniques and practices that characterized him for the rest of his career. Using evidence from Burnet's published work, as well as personal papers from the period he worked on the phages, this paper demonstrates the direct impact that his experiments with phages had on the development of his characteristic scientific style and approaches, which manifested themselves in his later career and theories, and especially in his thinking regarding various immunological problems.  相似文献   

20.
Meyen’s “Basic features of gymnosperm systematics and phylogeny as evidenced by the fossil record” departs from the usual Botanical Review article that provides the botanical community with a synthesis of the state of knowledge and understanding of an individual segment of botany, i.e., an interpretation of progress in a specialty for the nonspecialist. Instead, this article appears intended to challenge paleobotanists to reconsider traditional views of the interrelationships of the various gymnospermous groups and the concepts on which they were based. A classification scheme is presented which divides gymnosperms into the Ginkgoopsida, Cycadopsida and Pinopsida. These classes are based on Meyen’s analysis of the structural variation in gymnosperms and his interpretation of homologies of various organs. Too often, however, key plants are reconstructed from parts known only in association and relationships are tied to assumptions of homology that have yet to be documented. The result has value in providing a succinct summary of gymnospermous structure and variation in the different groups. It is also commendable in its attempt to explain and use concepts and terminology designed especially for gymnosperms. This critique shows that in many cases there are alternative interpretations that also fit the evidence.  相似文献   

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