365 days: 2014 in science
365 days: 2014 in science
复制标题
DOI：
10.1038/516300a
复制
发表时间：
2014-12
期刊：
影响因子：
64.8
通讯作者：
Lauren Morello;A. Abbott;D. Butler;E. Callaway;D. Cyranoski;S. Reardon;Q. Schiermeier;A. Witze
中科院分区：
文献类型：
--
作者：
Lauren Morello;A. Abbott;D. Butler;E. Callaway;D. Cyranoski;S. Reardon;Q. Schiermeier;A. Witze
HUMAN ORIGINS DECODED Considering that they have been dead for around 30,000 years, Neanderthals had a hell of a year. Their DNA survives in non-African human genomes, thanks to ancient interbreeding, and two teams this year catalogued humans’ Neanderthal heritage. Scientists learnt more about the sexual encounters between Homo neanderthalensis and early humans after analysing the two oldest Homo sapiens genomes on record—from men who lived in southwest Siberia 45,000 years ago and in western Russia more than 36,000 years ago, respectively. The DNA revealed hitherto-unknown human groups and more precise dates for when H. sapiens coupled with Neanderthals, which probably occurred in the Middle East between 50,000 and 60,000 years ago. Radiocarbon dating of dozens of archaeological sites in Europe, meanwhile, showed that humans and Neanderthals coexisted there for much longer than was once thought—up to several thousand years in some places.Genomes old and new charted the emergence of agriculture. Contemporary Europeans carry DNA inherited from light-skinned, brown-eyed farmers who migrated from the Middle East beginning 7,000–8,000 years ago, in addition to more-ancient ancestry. The achievements of these early farmers—domestication of crops such as wheat and barley—are also being understood through genome sequencing. In July, a consortium reported a draft copy of the gargantuan wheat genome, which contains 124,000 genes and 17 billion nucleotides. Another group released the genomes of 3,000 rice varieties. Genomes of the future may soon carry added information. Scientists in California engineered Escherichia coli bacteria to include two chemical nucleotides in their genome in addition to the four that all other life forms use. The next step is to harness the expanded genetic alphabet to produce new kinds of protein. An effort to synthesize an entire yeast genome produced its first chromosome this year.
