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Haplogroup T (Y-DNA)
Haplogroup T-M184, also known as Haplogroup T, is a human Y-chromosome DNA haplogroup. The unique-event polymorphism that defines this clade is the single-nucleotide polymorphism known as ''M184''. T-M184 is unusual in that it is both geographically widespread and relatively rare. T1 (T-L206) – the numerically dominant primary branch of T-M184 – appears to have originated in Western Asia, and spread from there into East Africa, South Asia, Europe, Egypt and adjoining regions. T1* may have expanded with the Pre-Pottery Neolithic B culture (PPNB) which originated in West Asia. Subclades of T-M70 appear to have been present in Europe since the Neolithic with Neolithic Farmers from Western Asia. The moderately high frequency (~18%) of T1b* chromosomes in the Lemba of southern Africa supports the hypothesis of a West Asian origin for their paternal line. Structure ;Subclade structure of Haplogroup T (M184). *T1 (L206) **T1a (M70/Page46/PF5662) ***T1a1 (L162/Page21, L454 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Before Present
Before Present (BP) or "years before present (YBP)" 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 1January 1950 as the commencement date (epoch) of the age scale, with 1950 being labelled as the "standard year". 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 account for when using radiocarbon dating for dates of origin that may fall after this year. 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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Single-nucleotide Polymorphism
In genetics and bioinformatics, a single-nucleotide polymorphism (SNP ; plural SNPs ) is a germline substitution of a single nucleotide at a specific position in the genome. Although certain definitions require the substitution to be present in a sufficiently large fraction of the population (e.g. 1% or more), many publications do not apply such a frequency threshold. For example, a Guanine, G nucleotide present at a specific location in a reference genome may be replaced by an Adenine, A in a minority of individuals. The two possible nucleotide variations of this SNP – G or A – are called alleles. SNPs can help explain differences in susceptibility to a wide range of diseases across a population. For example, a common SNP in the Factor H, CFH gene is associated with increased risk of age-related macular degeneration. Differences in the severity of an illness or response to treatments may also be manifestations of genetic variations caused by SNPs. For example, two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup L-M20
Haplogroup L-M20 is a human Y-DNA haplogroup, which is defined by SNPs M11, M20, M61 and M185. As a secondary descendant of haplogroup K and a primary branch of haplogroup LT, haplogroup L currently has the alternative phylogenetic name of K1a, and is a sibling of haplogroup T (a.k.a. K1b). The presence of L-M20 has been observed at varying levels throughout South Asia, peaking in populations native to the southern Pakistani province of Balochistan (28%), Northern Afghanistan (25%), and Southern India (19%). The clade also occurs in Tajikistan and Anatolia, as well as at lower frequencies in Iran. It has also been present for millennia at very low levels in the Caucasus, Europe and Central Asia. The subclade L2 (L-L595) has been found in Europe and Western Asia, but is extremely rare. Phylogenetic tree There are several confirmed and proposed phylogenetic trees available for haplogroup L-M20. The scientifically accepted one is the Y-Chromosome Consortium (YCC) one publis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic Name
Phylogenetic nomenclature is a method of nomenclature for taxa in biology that uses phylogenetic definitions for taxon names as explained below. This contrasts with the traditional method, by which taxon names are defined by a ''type'', which can be a specimen or a taxon of lower rank, and a description in words. Phylogenetic nomenclature is regulated currently by the '' International Code of Phylogenetic Nomenclature'' (''PhyloCode''). Definitions Phylogenetic nomenclature associates names with clades, groups consisting of an ancestor and all its descendants. Such groups are said to be monophyletic. There are slightly different methods of specifying the ancestor, which are discussed below. Once the ancestor is specified, the meaning of the name is fixed: the ancestor and all organisms which are its descendants are included in the taxon named. Listing all these organisms (i.e. providing a full circumscription) requires the complete phylogenetic tree to be known. In practice, there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haplogroup LT
Haplogroup LT or LT-L298/P326, also known as K1 (and until 2008 as Haplogroup K2), is a Y-chromosome DNA haplogroup. Its defining SNP mutations are L298 and P326. No confirmed cases of the basal paragroup LT* have been identified among living males or human remains. Structure It is generally believed that LT (L298/P326) originated somewhere in Asia. LT is a direct descendant of haplogroup K (M9). The direct descendants of LT are haplogroup L (M20), also known as K1a, and haplogroup T (M184), also known as K1b.International Society of Genetic Genealogy'', 2015, ''Y-DNA Haplogroup Tree 2015'' (30 May 2015). Distribution Y-DNA haplogroup LT is an old lineage widely distributed at low concentrations. It was established a ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paternal
A father is the male parent of a child. Besides the paternal bonds of a father to his children, the father may have a parental, legal, and social relationship with the child that carries with it certain rights and obligations. A biological father is the male genetic contributor to the creation of the infant, through sexual intercourse or sperm donation. A biological father may have legal obligations to a child not raised by him, such as an obligation of monetary support. An adoptive father is a man who has become the child's parent through the legal process of adoption. A putative father is a man whose biological relationship to a child is alleged but has not been established. A stepfather is a non-biological male parent married to a child's preexisting parent and may form a family unit but generally does not have the legal rights and responsibilities of a parent in relation to the child. The adjective "paternal" refers to a father and comparatively to "maternal" for a mother. Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pre-Pottery Neolithic B
Pre-Pottery Neolithic B (PPNB) is part of the Pre-Pottery Neolithic, a Neolithic culture centered in upper Mesopotamia and the Levant, dating to years ago, that is, 8800–6500 BC. It was Type site, typed by British archaeologist Kathleen Kenyon during her archaeological excavations at Jericho in the West Bank, territory of Palestine. Like the earlier PPNA people, the PPNB culture developed from the Mesolithic Natufian culture. However, it shows evidence of having more northerly origins, possibly indicating an influx from the region of northeastern Anatolia. Lifestyle Cultural tendencies of this period differ from that of the earlier Pre-Pottery Neolithic A (PPNA), in that people living during this phase began to depend more heavily upon domestication, domesticated animals to supplement their earlier mixed agrarian and hunter-gatherer diet. In addition, the flint tool kit of the period is new and quite disparate from that of the earlier period. One of its major elements is t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Egypt
Egypt ( , ), officially the Arab Republic of Egypt, is a country spanning the Northeast Africa, northeast corner of Africa and Western Asia, southwest corner of Asia via the Sinai Peninsula. It is bordered by the Mediterranean Sea to northern coast of Egypt, the north, the Gaza Strip of Palestine and Israel to Egypt–Israel barrier, the northeast, the Red Sea to the east, Sudan to Egypt–Sudan border, the south, and Libya to Egypt–Libya border, the west; the Gulf of Aqaba in the northeast separates Egypt from Jordan and Saudi Arabia. Cairo is the capital, list of cities and towns in Egypt, largest city, and leading cultural center, while Alexandria is the second-largest city and an important hub of industry and tourism. With over 109 million inhabitants, Egypt is the List of African countries by population, third-most populous country in Africa and List of countries and dependencies by population, 15th-most populated in the world. Egypt has one of the longest histories o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Europe
Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere. It is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, the Mediterranean Sea to the south, and Asia to the east. Europe shares the landmass of Eurasia with Asia, and of Afro-Eurasia with both Africa and Asia. Europe is commonly considered to be Boundaries between the continents#Asia and Europe, separated from Asia by the Drainage divide, watershed of the Ural Mountains, the Ural (river), Ural River, the Caspian Sea, the Greater Caucasus, the Black Sea, and the waterway of the Bosporus, Bosporus Strait. "Europe" (pp. 68–69); "Asia" (pp. 90–91): "A commonly accepted division between Asia and Europe ... is formed by the Ural Mountains, Ural River, Caspian Sea, Caucasus Mountains, and the Black Sea with its outlets, the Bosporus and Dardanelles." Europe covers approx. , or 2% of Earth#Surface, Earth's surface (6.8% of Earth's land area), making it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Asia
South Asia is the southern Subregion#Asia, subregion of Asia that is defined in both geographical and Ethnicity, ethnic-Culture, cultural terms. South Asia, with a population of 2.04 billion, contains a quarter (25%) of the world's population. As commonly conceptualised, the modern State (polity), states of South Asia include Bangladesh, Bhutan, India, the Maldives, Nepal, Pakistan, and Sri Lanka, with Afghanistan also often included, which may otherwise be classified as part of Central Asia. South Asia borders East Asia to the northeast, Central Asia to the northwest, West Asia to the west and Southeast Asia to the east. Apart from Southeast Asia, Littoral South Asia, Maritime South Asia is the only subregion of Asia that lies partly within the Southern Hemisphere. The British Indian Ocean Territory and two out of Atolls of Maldives, 26 atolls of the Maldives in South Asia lie entirely within the Southern Hemisphere. Topographically, it is dominated by the Indian subcontinent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Africa
East Africa, also known as Eastern Africa or the East of Africa, is a region at the eastern edge of the Africa, African continent, distinguished by its unique geographical, historical, and cultural landscape. Defined in varying scopes, the region is recognized in the United Nations Statistics Division United Nations geoscheme for Africa, scheme as encompassing 18 sovereign states and 4 territories. It includes the Horn of Africa to the North and Southeastern Africa to the south. Definitions In a narrow sense, particularly in English-speaking contexts, East Africa refers to the area comprising Kenya, Tanzania, and Uganda, largely due to their shared history under the Omani Empire and as parts of the British East Africa Protectorate and German East Africa. Further extending East Africa's definition, the Horn of Africa—comprising Djibouti, Eritrea, Ethiopia, and Somalia—stands out as a distinct geopolitical entity within East Africa.Robert Stock, ''Africa South of the Sahara, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
