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Origins of Life and Evolution of Biospheres - The RNA world hypothesis relies on the double-helix complementarity principle for both replication and catalytic activity of RNA. However, the de novo... 相似文献
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Fjeldså J Zuccon D Irestedt M Johansson US Ericson PG 《Proceedings. Biological sciences / The Royal Society》2003,270(Z2):S238-S241
Passerine birds are very plastic in their adaptations, which has made it difficult to define phylogenetic lineages and correctly allocate all species to these. Sapayoa aenigma, a member of the large group of New World flycatchers, has been difficult to place, and DNA-DNA hybridization experiments have indicated that it may have been misplaced. This is confirmed here, as base sequencing of two nuclear genes places it as a deep branch in the group of broadbills and pittas of the Old World tropics. The peculiar distribution of this lineage may be best explained in terms of a Gondwanic and Late Cretaceous origin of the passerine birds, as this particular lineage dispersed from the Antarctic landmass, reaching the Old World tropics via the drifting Indian plate, and South America via the West Antarctic Peninsula. 相似文献
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Daniel Cohen 《Science activities》2013,50(2):40-44
Bowden, Charles Killing the Hidden Waters Austin: University of Texas Press, 1977 174 pp., $9.96 Reviewed by Malcolm F. Farmer Cogswell, Howard L. Water Birds of California Berkeley: University of California Press, 1977 416 pp., $5.75 paper Reviewed by Karl L. Trever Grant, Edward Physical Science in the Middle Ages New York: Cambridge University Press, 1977 128 pp., $4.95 Reviewed by Emanuel D. Rudolph Piltz, Albert, and Robert Sund Creative Teaching of Science in the Elementary School, 2d ed. Boston: Allyn and Bacon, Inc., 1977 310 pp., $7.95 Reviewed by Herbert H. Grossman Lucas, David J., Harold I. James, John Simpson A First Science Dictionary: College Edition New York: Crane, Russak &; Company, Inc., 1977 206 pp., $8.50 Reviewed by Lawrence P. Eblin Gribben, John, ed. Climatic Change New York: Cambridge University Press, 1978 280 pp., $37.50 cloth, $11.95 paper Reviewed by Waring B. Hill Caroe, G.M. William Henry Bragg 1862–1942: Man and Scientist New York: Cambridge University Press, 1978 212 pp., $16.95 Reviewed by Gilbert Wright Rowe, Mary Budd Teaching Science as Continuous Inquiry: A Basic New York: McGraw-Hill Book Co., 1978 509 pp., $16.00 Reviewed by Elmer F. Kohlmiller Branley, Franklyn M. Color: From Rainbows to Lasers New York: Thomas Y. Crowell Co., 1978 87 pp., $8.95 Reviewed by Van E. Neie McNutt, Kristen W., and David R. McNutt Nutrition and Food Choices Chicago: Science Research Associates, Inc., 1978 506 pp., $10.36 Reviewed by Manfred Kroger Allen, Arthur James A Whaler and Trader in the Arctic: 1895–1944 Anchorage: Alaska Northwest Publishing Company, 1978 213 pp., $5.95 paper Reviewed by Vagn Flyger Coleman, William Biology in the Nineteenth Century: Problems of Form, Function, and Transformation, rev. ed. New York: Cambridge University Press, 1978 187 pp., $13.95 cloth, $5.95 paper Reviewed by Donald J. Zinn 相似文献
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