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T. C. Whitmore 《Plant Systematics and Evolution》1980,135(1-2):41-69
This first study of the whole genusAgathis makes use of recent local revisions of the New Caledonian and Australian species which are all maintained. The male cone is shown to have most of the taxonomically useful variation, and this confirms the findings of two partial revisions centred on Indonesian species. Thirteen species are recognized, two of which have two subspecies. New Caledonia has five, and Australia three, sympatric species. Otherwise the species are allopatric except for a few populations of central MalesianA. dammara within the range of west MalesianA. borneensis. One of these montane populations is the distinctiveA. dammara subsp.flavescens of Malaya, formerly a full species.Two groups and three individually distinctive species can be recognized on microsporophyll characters. The larger, group B, comprizes eight species,A. australis (New Zealand),A. corbassonii, A. lanceolata andA. montana (New Caledonia),A. macrophylla (Melanesian islands and includingA. obtusa andA. vitiensis),A. atropurpurea (Australia),A. dammara (mainly central Malesia) andA. borneensis (west Malesia); both the last have long synonymies. The smaller species, group (A), comprizesA. microstachya (Australia) andA. labillardieri (west New Guinea and the Sepik basin). The individually distinctive species areA. moorei andA. ovata of New Caledonia andA. robusta of Australia with its new subspeciesnesophila, described here, of eastern New Guinea and New Britain. 相似文献
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M. A. Hofman 《Human Evolution》1988,3(3):177-188
Allometric scaling models, used to describe morphological and functional relationships between two sets of observations, are examined both in concept and in application. This paper focuses on the underlying assumptions and statistics of the methods most frequently used: linear regression, principal axis and standard major axis analysis. It is shown that the standard major axis (SMA) is the most appropriate bivariate linear model in palaeonotological research. Differences among the models discussed are illustrated by a morphometric analysis of dental dimensions in australopithecines. 相似文献
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C. I. MACADIE 《Zoological Journal of the Linnean Society》1967,47(311):251-253
The Ultrasonic Probe was specially designed, patented and made by the Simms Group Research and Development Limited, London, during Dr E. I. White's final year of office as Keeper of Palaeontology at the British Museum (Natural History). It utilizes the same principles as those of ultrasonic tanks (Firth, 1960; Organ, 1959). The probe tip vibrates at a very high frequency and causes cavitation in the cleaning fluid, which breaks up porous and incompetent matrices. Its small diameter and area of activity make it invaluable when only parts of a specimen require cleaning, or when specimens are too big for the tank. 相似文献
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A. A. Manten 《Review of Palaeobotany and Palynology》1970,10(4):245-248
Whereas zoopalaeontology is one-sidedly a geological science, palaeobotany is predominantly a science cultivated by biologists. Under the influence of increased application as a stratigraphical and palaeoenvironmentological tool in exploration geology as well as in pure geology, palaeopalynology is also becoming more and more a one-sidedly orientated field of science. 相似文献
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R P Ambler M Daniel 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》1991,333(1268):381-389
Protein taxonomy has existed as a concept at least since 1958, but despite the efforts of the past 30 years, comparative studies of protein sequence, structure and distribution have not revolutionized any areas of systematics. The most interesting results of single gene phylogenies have been the anomalies, such as insulin in hystricomorphs or cytochrome c in the rattlesnake. It is likely that protein sequence information can be obtained in sufficient quality and quantity from ancient material as to change this finding? The paper will assess possibilities and the likely limitations of chemical studies of ancient protein material. 相似文献
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ADRIAN DESMOND 《Zoological Journal of the Linnean Society》1984,82(1-2):7-16
New sociological techniques in the history of science are described. Their value is illustrated by reinterpreting the diagnostic disputes which occurred following the first discovery of the Stonesfield mammals. It is concluded that contextual explanations are more sympathetic to early savants and more conducive to the integration of science and social history. 相似文献
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Churcher I Ashton K Butcher JW Clarke EE Harrison T Lewis HD Owens AP Teall MR Williams S Wrigley JD 《Bioorganic & medicinal chemistry letters》2003,13(2):179-183
A new series of benzodiazepine-containing gamma-secretase inhibitors with potential use in the treatment of Alzheimer's disease is disclosed. Structure-activity relationships of the pendant hydrocinnamate side-chain which led to the preparation of highly potent inhibitors are described. 相似文献