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Haplogroup P (Y-DNA)
Haplogroup P also known as P-P295 and K2b2 is a Y-chromosome DNA haplogroup in human genetics. P-P295 is a branch of K2b (previously Haplogroup MPS; P331), which is a branch of Haplogroup K2 (K-M526). The only primary branches (clades) of P-P295 are P1 (P-M45) commonly found among Siberians and Central Asians, and P2 (P-B253) found in Oceanian populations. along with P* found among an Indian sample in Malayasia. P1 (P-M45) Many ethnic groups with high frequencies of P1, also known as P-M45 and K2b2a, are located in Central Asia and Siberia: 35.4% among Tuvans, 28.3% among Altai-Kizhi (PxQ-M3,R1), and 35% among Nivkh males. ยง ''May include members of haplogroup R2.'' Q Near universal in the Kets (95%) of Siberia. Very common in pre-modern Native American populations and Selkups, except for the Na-Dene peoples, where it reaches 50-90%. Also common, at 25-50% in Siberian populations such as the Siberian Tatars, Nivkh, Tuvans, Chukchi, Siberian Eskimos, Northern A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Before Present
Before Present (BP) years, or "years before present", is a time scale used mainly in archaeology, geology and other scientific disciplines to specify when events occurred relative to the origin of practical radiocarbon dating in the 1950s. Because the "present" time changes, standard practice is to use 1 January 1950 as the commencement date (epoch) of the age scale. The abbreviation "BP" has been interpreted retrospectively as "Before Physics", which refers to the time before nuclear weapons testing artificially altered the proportion of the carbon isotopes in the atmosphere, which scientists must now account for. In a convention that is not always observed, many sources restrict the use of BP dates to those produced with radiocarbon dating; the alternative notation RCYBP stands for the explicit "radio carbon years before present". Usage The BP scale is sometimes used for dates established by means other than radiocarbon dating, such as stratigraphy. This usage differs from t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
