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1.
SYNOPSIS. It was exactly 300 years ago this month (August 1974) that the 17th century modest draper from Delft, Holland—Antony van Leeuwenhoek—discovered protozoa. Describing them, often with amazing accuracy considering the optical equipment he was using (simply a home-made “glorified”hand lens), in letters to the Royal Society of London, he established himself, certainly, as the founding father of protozoology. It is particularly appropriate for an assemblage of protozoologists to pay homage to this intrepid “philosopher in little things,”a man with an insatiable curiosity about his wee animalcules, on the tricentenary of his discovery of them, since it was an event of such long-lasting significance.  相似文献   

2.
Although not laying claim to being the inventor of the light microscope, Antonj van Leeuwenhoek (1632–1723) was arguably the first person to bring this new technological wonder of the age properly to the attention of natural scientists interested in the study of living things (people we might now term ‘biologists’). He was a Dutch draper with no formal scientific training. From using magnifying glasses to observe threads in cloth, he went on to develop over 500 simple single lens microscopes (Baker & Leeuwenhoek 1739 Phil. Trans. 41, 503–519. (doi:10.1098/rstl.1739.0085)) which he used to observe many different biological samples. He communicated his finding to the Royal Society in a series of letters (Leeuwenhoek 1800 The select works of Antony Van Leeuwenhoek, containing his microscopical discoveries in many of the works of nature, vol. 1) including the one republished in this edition of Open Biology. Our review here begins with the work of van Leeuwenhoek before summarizing the key developments over the last ca 300 years, which has seen the light microscope evolve from a simple single lens device of van Leeuwenhoek''s day into an instrument capable of observing the dynamics of single biological molecules inside living cells, and to tracking every cell nucleus in the development of whole embryos and plants.  相似文献   

3.
Summary and conclusions Leeuwenhoek's observations relating to animal population, though scattered through many letters written during a period of over forty years, when seen in toto, were important contributions to the subject now known as animal demography. He maintained enough contact with other scientists to have received encouragement and some helpful suggestions, but the language barrier and the novelty of doing microscopic work forced him to be resourceful, inventive, and original. His multifarious investigations impinged upon population biology before he discovered a direct interest in it. He devised methods for estimating numbers of animalcules, and then he went on to estimate the population of the world. His interest in reproduction was an important avenue by which he approached the subject of reproductive capacity. Other important approaches were his studies of growth, longevity, and life histories. He discovered relationships between aspects of the life history, longevity, and reproductive capacity of several species of insects, notably calanders, scavenger flies, crane flies, aphids, and lice. An important feature of these investigations were the arithmetical calculations which he made of reproductive potentials. In spite of several limitations, these calculations were an important innovation to the study of animal population. In his later years, his investigations came more and more within the sphere of ecology. He made the first significant observations on food chains. It is especially interesting that fish were the subject of these observations, because it was not until the latter half of the nineteenth century that scientists realized that fish ultimately depend upon phytoplankton.These accomplishments did not pass unnoticed. Although Leeuwenhoek never synthesized his scattered observations concerning population, his originality and perception were appreciated by outstanding biologists of the eighteenth century. The important discussions of population biology by Réaumur, Buffon, and Bonnet all derived inspiration and assistance from the writings of Leeuwenhoek.73 This ingenious Fellow of the Royal Society, by detecting through diligent application and scrutiny the mysteries of Nature and the secrets of natural philosophy,74 became one of the founders of animal demography.  相似文献   

4.
The paper discusses A.W. Howitt's position as an amateur of science in colonial Gippsland, and explores connections between his geological and anthropological endeavours. Two contexts contributed to the kind of anthropology he did. and the kinds of works he wrote. One is the point on the trajectory of the colonial history of Victoria when Howitt joined it and began his researches. The other is the moment in the development of anthropology when he and his sister Anna Mary Howitt began to read and correspond about the discipline, and he began to correspond with other practitioners. Geology was linked to Howitt's anthropology in two ways: through his working life in Gippsland, and in models that informed the evolutionary paradigm within which his anthropological research and writing were situated.  相似文献   

5.
American Biologist Martin Chalfie shared the 2008 Nobel Prize in Chemistry with Roger Tsien and Osamu Shimomura for their discovery and development of the Green Fluorescent Protein (GFP).Martin Chalfie was born in Chicago in 1947 and grew up in Skokie Illinois. Although he had an interest in science from a young age-- learning the names of the planets and reading books about dinosaurs-- his journey to a career in biological science was circuitous. In high school, Chalfie enjoyed his AP Chemistry course, but his other science courses did not make much of an impression on him, and he began his undergraduate studies at Harvard uncertain of what he wanted to study. Eventually he did choose to major in Biochemistry, and during the summer between his sophomore and junior years, he joined Klaus Weber''s lab and began his first real research project, studying the active site of the enzyme aspartate transcarbamylase. Unfortunately, none of the experiments he performed in Weber''s lab worked, and Chalfie came to the conclusion that research was not for him.Following graduation in 1969, he was hired as a teacher Hamden Hall Country Day School in Connecticut where he taught high school chemistry, algebra, and social sciences for 2 years. After his first year of teaching, he decided to give research another try. He took a summer job in Jose Zadunaisky''s lab at Yale, studying chloride transport in the frog retina. Chalfie enjoyed this experience a great deal, and having gained confidence in his own scientific abilities, he applied to graduate school at Harvard, where he joined the Physiology department in 1972 and studied norepinephrine synthesis and secretion under Bob Pearlman. His interest in working on C. elegans led him to post doc with Sydney Brenner, at the Medical Research Council Laboratory of Molecular Biology in Cambridge, England. In 1982 he was offered position at Columbia University.When Chalfie first heard about GFP at a research seminar given by Paul Brehm in 1989, his lab was studying genes involved in the development and function of touch-sensitive cells in C. elegans. He immediately became very excited about the idea of expressing the fluorescent protein in the nematode, hoping to figure out where the genes were expressed in the live organism. At the time, all methods of examining localization, such as antibody staining or in situ hybridization, required fixation of the tissue or cells, revealing the location of proteins only at fixed points in time.In September 1992, after obtaining GFP DNA from Douglas Prasher, Chalfie asked his rotation student, Ghia Euskirchen to express GFP in E. coli, unaware that several other labs were also trying to express the protein, without success. Chalfie and Euskirchen used PCR to amplify only the coding sequence of GFP, which they placed in an expression vector and expressed in E.coli. Because of her engineering background, Euskirchen knew that the microscope in the Chalfie lab was not good enough to use for this type of experiment, so she captured images of green bacteria using the microscope from her former engineering lab. This work demonstrated that GFP fluorescence requires no component other than GFP itself. In fact, the difficulty that other labs had encountered stemmed from their use of restriction enzyme digestions for subcloning, which brought along an extra sequence that prevented GFP''s fluorescent expression. Following Euskirchen''s successful expression in E. coli, Chalfie''s technician Yuan Tu went on to express GFP in C. elegans, and Chalfie published the findings in Science in 1994.Through the study of C. elegans and GFP, Chalfie feels there is an important lesson to be learned about the importance basic research. Though there has been a recent push for clinically-relevant or patent-producing (translational) research, Chalfie warns that taking this approach alone is a mistake, given how "woefully little" we know about biology. He points out the vast expanse of the unknowns in biology, noting that important discoveries such as GFP are very frequently made through basic research using a diverse set of model organisms. Indeed, the study of GFP bioluminescence did not originally have a direct application to human health. Our understanding of it, however, has led to a wide array of clinically-relevant discoveries and developments. Chalfie believes we should not limit ourselves: "We should be a little freer and investigate things in different directions, and be a little bit awed by what we''re going to find."Download video file.(152M, mp4)  相似文献   

6.
Tracing the contributions of Edgar Anderson (1897--1969) of the Missouri Botanical Garden to the important discussions in evolutionary biology in the 1940s, this paper argues that Anderson turned to corn research rather than play a more prominent role in what is now known as the Evolutionary Synthesis. His biosystematic studies of Iris and Tradescantia in the 1930s reflected such Synthesis concerns as the species question and population thinking. He shared the 1941 Jesup Lectures with Ernst Mayr. But rather than preparing his lectures as a potentially key text in the Synthesis, Anderson began researching Zea mays -- its taxonomy, its origin, and its agronomic role. In this study, Anderson drew on the disciplines of taxonomy, morphology, genetics, geography, anthropology, archaeology, and agronomy among others in his own creative synthesis. Though his maize research in the 1940s represented the most sustained work of his career, Anderson was also drawn in many directions during his professional life. For example, he enjoyed teaching, working with amateurs, and popular writing. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   

7.
8.

Background

Linnaeus developed a robust system for naming plants and a useful, if mechanical, system for classifying them. His binomial nomenclature proved the catalyst for the rapid development of our knowledge of orchids, with his work on the family dating back to 1737 in the first edition of his Genera Plantarum. His first work devoted to orchids, indeed the first monograph of the family, was published in 1740 and formed the basis for his account in Species Plantarum, published in 1753, in which he gave a binomial name to each species. Given the overwhelming number of orchids, he included surprisingly few – only 62 mostly European species – in Species Plantarum, his seminal work on the plants of the world. This reflects the European origin of modern botany and the concentration of extra-European exploration on other matters, such as conquest, gold and useful plants. Nevertheless, the scope of Linnaeus'' work is broad, including plants from as far afield as India, Japan, China and the Philippines to the east, and eastern Canada, the West Indies and northern South America to the west. In his later publications he described and named a further 45 orchids, mostly from Europe, South Africa and the tropical Americas.

Scope

The philosophical basis of Linnaeus'' work on orchids is discussed and his contribution to our knowledge of the family assessed. His generic and species concepts are considered in the light of current systematic ideas, but his adoption of binomial nomenclature for all plants is his lasting legacy.Key words: Classification, Linnaeus, nomenclature, Orchidaceae, orchids  相似文献   

9.
10.
It is now almost 100 years since Hugh Campbell Ross began his experiments on white blood cells and cancer. By suspending peripheral blood cells in a solution of agar gel, he was able to observe changes in them provoked by various natural and artificial substances, which he named auxetics, kinetics, or augmentors, depending on the effects they produced. After his early experience he focused his attention particularly on lymphocytes in peripheral blood samples; he claimed to have observed rapid division in them, although at that time they were looked upon as end cells without a future. He contended that his results challenged what had become the orthodox view of the role of the nucleus in mitosis, asserting that cytologists had been led astray by relying on examination of fixed, dead structures. When doubt was cast on his claim to have induced cell division, his brother Ronald, Nobel laureate in physiology or medicine, came to his defense, but to no avail, and although he continued his experiments for a number of years they were quietly forgotten. Fifty years later the occurrence of mitotic division of peripheral blood lymphocytes was established beyond any doubt by Nowell and Hirschhorn.  相似文献   

11.
12.
Vig K 《ZooKeys》2011,(157):159-179
The excellence of Károly Sajó as a researcher into Hungary’s natural history has been undeservedly neglected. Yet he did lasting work, especially in entomology, and a number of his discoveries and initiatives were before their time.Born in 1851 in Győr, he received his secondary education there and went to Pest University. He taught in a grammar school in 1877–88 before spending seven years as an entomologist at the National Phylloxera Experimental Station, later the Royal Hungarian State Entomological Station. Pensioned off at his own request in 1895, he moved to Őrszentmiklós, where he continued making entomological observations on his own farm and wrote the bulk of his published materials: almost 500 longer or shorter notes, articles and books, mainly on entomological subjects.Sajó was among the first in the world to publish in 1896 a study of how the weather affects living organisms, entitled Living Barometers. His Sleep in Insects, which appeared in the same year, described his discovery, from 1895 observations of the red turnip beetle, Entomoscelis adonidis (Pallas, 1771), of aestivation in insects – in present-day terms diapause.It was a great loss to universal entomology when Sajó ceased publishing about 25 years before his death. His unpublished notes, with his library and correspondence, were destroyed in the World War II. His surviving insect collection is now kept in the Hungarian Natural History Museum, Budapest.  相似文献   

13.
G. O. Sars and the Norwegian Cladocera: a continuing frustration   总被引:4,自引:4,他引:0  
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14.
《Comptes Rendus Palevol》2002,1(7):649-656
Born on 16 March 1794 in Hamburg as a son of a Huguenot family whose members made big fortune as ship-owners, Ami Boué took his doctor’s degree in medicine in 1817 at the University of Edinburgh. During the following years, he completed his knowledge in the field of natural sciences, especially in Geoscience. In 1830, after having founded, with other scientists, among whom Constant Prévost and Gérard-Paul Deshayes, the Geological Society of France, in which Boué became the first president, he left Paris in 1835 and settled in Vienna. In 1836, 1837 and 1838 he crossed the Balkans. In his masterpiece La Turquie d’Europe (Paris, 1840, four volumes), he published the results of this research. In his study, Ami Boué intended to join the Austrian empire with Turkey by railways. Anyway, Boué’s works concerning the Balkans were fundamental for the future generations of Austrian geoscientists.  相似文献   

15.
C. Giles Miller 《ZooKeys》2016,(550):71-81
Sherborn’s work on the Foraminifera clearly provided the initial spark to compile the major indexes for which he is famous. Contact and help from famous early micropalaeontologists such as T. Rupert Jones and Fortescue William Millett led Sherborn to produce his Bibliography of Foraminifera and subsequently a two-part Index of Foraminiferal Genera and Species. Edward Heron-Allen, whose mentor was Millett, was subsequently inspired by the bibliography to attempt to acquire every publication listed. This remarkable collection of literature was donated to the British Museum (Natural History) in 1926 along with the foraminiferal collections Heron-Allen had mainly purchased from early micropalaeontologists. This donation forms the backbone of the current NHM micropalaeontological collections. The NHM collections contain a relatively small amount of foraminiferal material published by Sherborn from the London Clay, Kimmeridge Clay and Speeton Clay. Another smaller collection reflects his longer-term interest in the British Chalk following regular fieldwork with A. W. Rowe. Other collections relating to Sherborn’s early published work, particularly with T. R. Jones, are not present in the collections but these collections may have been sold or deposited elsewhere by his co-workers.  相似文献   

16.
17.
Upon returning from his voyage on the Beagle, Darwin prepared reports of his geological observations. Together, these reveal Darwin's approach to reasoning about geology. Darwin argued that successive terraces prove a very gradual elevation of the coast that lagoon islands show a reciprocal sinking of the oceanic floor. Hence, Darwin reinforced Lyell's uniformitarian, or steady state theory. Unlike lagoon islands, the movement of erratic boulders onto the plains is evidence of forces, which do not now exist. Darwin and Lyell attributed this movement to floating icebergs. However, mountain formation remained difficult for them to explain with reference to contemporary causes. Lyell discovered uplifts in Scandinavia, which resulted from epirogenesis, whereas mountain formation is an orogenesis, which involves both folding and uplift. Darwin was more impressed by uplift than by folds. However, when in Cordillera he saw strata overturned by masses of injected rock, proving successive periods of violence, Darwin took a position, which was closer to the plutonic theories of von Buch and Humboldt than it was to Lyell's uniformitarian views.  相似文献   

18.
19.
Hubel D  Wiesel T 《Neuron》2012,75(2):182-184
While attending medical school at McGill, David Hubel developed an interest in the nervous system during the summers he spent at the Montreal Neurological Institute. After heading to the United States in 1954 for a Neurology year at Johns Hopkins, he was drafted by the army and was assigned to the Neuropsychiatry Division at the Walter Reed Hospital, where he began his career in research and did his first recordings from the visual cortex of sleeping and awake cats. In 1958, he moved to the lab of Stephen Kuffler at Johns Hopkins, where he began a long and fruitful collaboration with Torsten Wiesel. Born in Sweden, Torsten Wiesel began his scientific career at the Karolinska Institute, where he received his medical degree in 1954. After spending a year in Carl Gustaf Bernhard's laboratory doing basic neurophysiological research, he moved to the United States to be a postdoctoral fellow with Stephen Kuffler. It was at Johns Hopkins where he met David Hubel in 1958, and they began working together on exploring the receptive field properties of neurons in the visual cortex. Their collaboration continued until the late seventies. Hubel and Wiesel's work provided fundamental insight into information processing in the visual system and laid the foundation for the field of visual neuroscience. They have had many achievements, including--but not limited to--the discovery of orientation selectivity in visual cortex neurons and the characterization of the columnar organization of visual cortex through their discovery of orientation columns and ocular-dominance columns. Their work earned them the Nobel Prize for Physiology or Medicine in 1981, which they shared with Roger Sperry.  相似文献   

20.
Thomas Hunt Morgan taught at Bryn Mawr College from 1891 until1904. During his years there he concentrated his research interestson embryology; he included regeneration as an integral partof development. This article maintains that Morgan did not abandonhis interest in embryology when he became a geneticist at Columbia,but it deals mainly with his teaching and research while atBryn Mawr. He worked on the development of a great diversityof organisms, plant and animal, he used widely differing experimentalmethods to investigate them, and he concerned himself with manydifferent general and special problems. He strove to investigateproblems that were directly soluble by experimental intervention,and was highly critical, in the best possible way, of the experimentsand interpretations made by his contemporaries, who regardedhim as a leader. He exerted his influence on developmental biologynot only through his research, but also through a number offine textbooks, and by his teaching. During his Bryn Mawr yearshe encouraged his students, undergraduate and graduate, to carryout independent research. He sometimes published with them asco-author, but dozens of articles by his students were publishedwithout carrying Morgan's name as co-author.  相似文献   

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