نتایج جستجو برای: ancient dna

تعداد نتایج: 542037  

2018
Antonia T Rodrigues Iain McKechnie Dongya Y Yang

Rockfish (Sebastes spp.) are a common marine fish in nearshore and continental shelf environments in the North Pacific Ocean. They are frequently identified in coastal archaeological sites in western North America; however, the morphological similarity of rockfish species limits conventional zooarchaeological identifications to the genus level. This study applies ancient DNA analysis to 96 arch...

Journal: :journal of agricultural science and technology 2010
h. mahmoudi nasab m. mardi h. talaee h. fazeli nashli s. m. pirseyedi

to determine ancient seed species, 3250-3450 year-old charred seeds obtained from different iranian archaeological sites were studied using scanning electron microscopy (sem) and molecular analysis. sem analysis of ancient seeds revealed that the surface of the seeds was damaged. therefore, we could not accurately identify their species. molecular analysis on ancient specimens was done on diffe...

2011
Kay Prüfer

Recent advancements in sequencing technologies have made it possible to sequence large quantities of the DNA preserved in ancient remains. This DNA differs from modern DNA in three key aspects. First, the DNA is fragmented into short molecules. Second, the DNA is damaged leading to misreads bases during sequencing. Last, molecules from the ancient species are mixed with molecules from microbial...

Journal: :Molecular ecology resources 2015
Martyna Molak Marc A Suchard Simon Y W Ho David W Beilman Beth Shapiro

Studies of DNA from ancient samples provide a valuable opportunity to gain insight into past evolutionary and demographic processes. Bayesian phylogenetic methods can estimate evolutionary rates and timescales from ancient DNA sequences, with the ages of the samples acting as calibrations for the molecular clock. Sample ages are often estimated using radiocarbon dating, but the associated measu...

Journal: :Molecular ecology 2014
Vendela K Lagerholm Edson Sandoval-Castellanos Dorothee Ehrich Natalia I Abramson Adam Nadachowski Daniela C Kalthoff Mietje Germonpré Anders Angerbjörn John R Stewart Love Dalén

The Pleistocene glacial cycles resulted in significant changes in species distributions, and it has been discussed whether this caused increased rates of population divergence and speciation. One species that is likely to have evolved during the Pleistocene is the Norwegian lemming (Lemmus lemmus). However, the origin of this species, both in terms of when and from what ancestral taxon it evolv...

Journal: :Molecular ecology 2016
Nathan K Schaefer Beth Shapiro Richard E Green

It is well established that related species hybridize and that this can have varied but significant effects on speciation and environmental adaptation. It should therefore come as no surprise that hybridization is not limited to species that are alive today. In the last several decades, advances in technologies for recovering and sequencing DNA from fossil remains have enabled the assembly of h...

Journal: :Human biology 2015
Yu Dong Chunxiang Li Fengshi Luan Zhenguang Li Hongjie Li Yinqiu Cui Hui Zhou Ripan S Malhi

To gain insight into the social organization of a population associated with the Dawenkou period, we performed ancient DNA analysis of 18 individuals from human remains from the Fujia site in Shandong Province, China. Directly radiocarbon dated to 4800-4500 cal BP, the Fujia site is assumed to be associated with a transitional phase from matrilineal clans to patrilineal monogamous families. Our...

2011
Clio Der Sarkissian

................................................................................................... 10 Thesis declaration .................................................................................... 11 Acknowledgments ................................................................................... 12 General Introduction ..................................................................

Journal: :journal of sciences islamic republic of iran 0

research on ancient dna (adna) has the potential to enable molecular biologists and archeologists to decipher certain aspects of history by direct looking into the past. however, several major problems in this field limit the applicability of adna studies, most importantly contamination with modern dna and postmortem dna degradation. in this study we extracted and analyzed adna obtained from ~3...

2015
Clemens L Weiß Michael Dannemann Kay Prüfer Hernán A Burbano

Contamination with exogenous DNA is a constant hazard to ancient DNA studies, since their validity greatly depend on the ancient origin of the retrieved sequences. Since contamination occurs sporadically, it is fundamental to show positive evidence for the authenticity of ancient DNA sequences even when preventive measures to avoid contamination are implemented. Recently the presence of wheat i...

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