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31.
JAIME LIRA† ANNA LINDERHOLM‡ CARMEN OLARIA§ MIKAEL BRANDSTRÖM DURLING¶ M. THOMAS P. GILBERT HANS ELLEGREN†† ESKE WILLERSLEV KERSTIN LIDÉN‡ JUAN LUIS ARSUAGA† ANDERS GÖTHERSTRÖM†† 《Molecular ecology》2010,19(1):64-78
Multiple geographical regions have been proposed for the domestication of Equus caballus . It has been suggested, based on zooarchaeological and genetic analyses that wild horses from the Iberian Peninsula were involved in the process, and the overrepresentation of mitochondrial D1 cluster in modern Iberian horses supports this suggestion. To test this hypothesis, we analysed mitochondrial DNA from 22 ancient Iberian horse remains belonging to the Neolithic, the Bronze Age and the Middle Ages, against previously published sequences. Only the medieval Iberian sequence appeared in the D1 group. Neolithic and Bronze Age sequences grouped in other clusters, one of which (Lusitano group C) is exclusively represented by modern horses of Iberian origin. Moreover, Bronze Age Iberian sequences displayed the lowest nucleotide diversity values when compared with modern horses, ancient wild horses and other ancient domesticates using nonparametric bootstrapping analyses. We conclude that the excessive clustering of Bronze Age horses in the Lusitano group C, the observed nucleotide diversity and the local continuity from wild Neolithic Iberian to modern Iberian horses, could be explained by the use of local wild mares during an early Iberian domestication or restocking event, whereas the D1 group probably was introduced into Iberia in later historical times. 相似文献
32.
New gastropods from East Pacific hydrothermal vents 总被引:4,自引:1,他引:3
The following new prosobranch species are described: Cyuthermia (gen.n.) naticoides, Lucunoidc (gen.n.) exquisitus (Neomphalidae); Peltospira Iamellifera, Pachydermia (gen.n.) laevis, Depressigyra (gen. n.) g1obulus. D. plunispira, Solutigyra (gen. n.) reticulata, Lirapex (gen. n.) humata, L. granularis (Peltospiridae); Bathymargarites (gen.n.) symplector (Trochidae) and Provanna mucleani (Littorinoidea). Shells and soft parts of the species are described and figured. One species each of Sinezona (Scissurellidae), Moel1rriopsis (Seguenzoidea) and Phymorrhynchus (Turridae) is recorded from East Pacific hydrothermal vents, but not identified to species. Information about feeding biology and type of larval development is given for most of these species. The systematic position of the new species of Neomphalidae and Peltospiridae is considered uncertain, but further anatomical investigations are in progress. The gastropod fauna of East Pacific sulphide-rich environments is summarized and composition, endemism, age. dispersal, predation, adaptations and feeding biology are discussed. 相似文献
33.
ANDERS MARTINSSON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1983,16(3):206-206
Day, Robert A. 1979: How to Write and Publish a Scientific-Paper. 160 pp. ISI Press, Philadelphia. ISBN 0 894950088 (cloth), ISBN 0894950061 (paperback). Price USD 15.00 and 8.95, respectively.
Cremmins, Edward T. 1982: The Art of Abstracting. 145 pp. ISI Press, Philadelphia. ISBN 0894950150. Price USD 13.95 (paperback).
Barnes, Gregory A. 1982: Communication Skills for the Foreign-Born Professional. ISI Press, Philadelphia. ISBN 0894950134 (cloth). ISBN 0894950142 (paperback). Price USD 18.95 and 13.95, respectively. 相似文献
Cremmins, Edward T. 1982: The Art of Abstracting. 145 pp. ISI Press, Philadelphia. ISBN 0894950150. Price USD 13.95 (paperback).
Barnes, Gregory A. 1982: Communication Skills for the Foreign-Born Professional. ISI Press, Philadelphia. ISBN 0894950134 (cloth). ISBN 0894950142 (paperback). Price USD 18.95 and 13.95, respectively. 相似文献
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ANDERS MARTINSSON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1976,9(1):107-109
Symposia and congresses (and similarly named conferences) provide a specific medium for scientific communication that should complement, not duplicate, published or circularized reporting. The total expenditure for presentation of results at a session of the International Geological Congress is at least in the region of 8 million dollars, and there are hundreds of smaller geological meetings every year. Progress in finding rational forms for meetings is slow, and elementary deficiencies in meeting organization are incessantly repeated. The fact that meetings have established themselves as a very viable institution in science provides no excuse for not watching and reviewing their structure and economy as vigilantly as, for example, publications. 相似文献
38.
In the present study 241 shells from snails belonging to theBulinus africanus-group in West Africa, were examined in a morphometricanalysis including ten characters. Principal component analysisand stepwise discriminant function analysis were used for analysisof the data. It was shown that Bulinus umbilicatus, B. jousseaumeiand B. globosus are clearly distinct on morphometric shell characters.Besides a general differentiation between the three species,the characters necessary for differentiation between them twoby two are found. The knowledge of the geographic distributionof B. umbilicatus and B. jousseaumei is significantly improved. (Received 18 March 1988; accepted 4 May 1988) 相似文献
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ANDERS MARTINSSON 《Lethaia: An International Journal of Palaeontology and Stratigraphy》1976,9(4):459-462
The two large organizations in international geology, the permanent International Union of Geological Sciences (IUGS) and the long-term International Geological Correlation Programme (IGCP), are strongly stratified units and victims of platform sedimentation. Their National Committees and corresponding bodies are often useless as channels of the active scientists' initiative and influence. Their constituent and affiliated scientific bodies are deprived of all influence on the management of the organizations, in favour of managements bureaucratically and autocratically recruited according to a pattern of equitable geographical distribution. The IGCP is wasting effort in hunting for programme gaps, whilst both organizations are campaigning against regional concentrations of interest and consequent influence. Both organizations are in bad need of activating their national members and opening up their management to influence from their scientific bodies. For this purpose important changes in their constitutions are needed. Only then can their formal strength become real and their many challenging tasks be efficiently tackled. 相似文献