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ROBERT J. SMITH 《American anthropologist》1971,73(6):1318-1319
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Molecular markers have become a fundamental piece of modern biology’s toolkit. In the last decade, new genomic resources from model organisms and advances in DNA sequencing technology have altered the way that these tools are developed, alleviating the marker limitation that researchers previously faced and opening new areas of research for studies of non‐model organisms. This availability of markers is directly responsible for advances in several areas of research, including fine‐scaled estimation of population structure and demography, the inference of species phylogenies, and the examination of detailed selective pressures in non‐model organisms. This review summarizes methods for the development of large numbers of DNA markers in non‐model organisms, the challenges encountered when utilizing different methods, and new research applications resulting from these advances. 相似文献
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THE GEOMETRY OF PLANT EPIDERMAL CELLS 总被引:4,自引:3,他引:1
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Capercaillie Tetrao urogallus numbers declined in Scottish forests between 1992 and 1997, although the rate (mean 16% per year, 95% CL 1–30%) differed among forests. Hens declined more quickly than cocks despite the sex ratio in chicks favouring females. A probable explanation is that adult cocks lived longer. Juvenile survival was less than adult survival, largely because juveniles were more likely to die from hitting fences. Although poor reproduction was probably the main cause of the decline, this might not have occurred had fence strikes been substantially fewer. 相似文献
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CRAIG ALAN K.; DOBKIN SHELDON; GRIMM ROBERT B.; DAVIDSON J. BLAINE 《Integrative and comparative biology》1969,9(3):895-901
The marine gastropod, Siphonaria pectinata, has an active partin the complex formation of secondary solution features characteristicof outcroppings of beach rock in south Florida. Analyses weremade of the distribution, anatomy, and feeding activity ofthissnail. The results show that these molluscs are concentratedin areas of maximum algal growth. While grazing they rasp substratapresoftened by algae so that new rock surfaces are continuallyexposed to biochemical erosion. 相似文献