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African Eve
In human genetics, the Mitochondrial Eve (also ''mt-Eve, mt-MRCA'') is the matrilineal most recent common ancestor (MRCA) of all living humans. In other words, she is defined as the most recent woman from whom all living humans descend in an unbroken line purely through their mothers and through the mothers of those mothers, back until all lines converge on one woman. In terms of mitochondrial haplogroups, the mt-MRCA is situated at the divergence of macro-haplogroup L into L0 and L1–6. As of 2013, estimates on the age of this split ranged at around 155,000 years ago, consistent with a date later than the speciation of ''Homo sapiens'' but earlier than the recent out-of-Africa dispersal. The male analog to the "Mitochondrial Eve" is the "Y-chromosomal Adam" (or Y-MRCA), the individual from whom all living humans are patrilineally descended. As the identity of both matrilineal and patrilineal MRCAs is dependent on genealogical history (pedigree collapse), they need not ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Year
A year or annus is the orbital period of a planetary body, for example, the Earth, moving in its orbit around the Sun. Due to the Earth's axial tilt, the course of a year sees the passing of the seasons, marked by change in weather, the hours of daylight, and, consequently, vegetation and soil fertility. In temperate and subpolar regions around the planet, four seasons are generally recognized: spring, summer, autumn and winter. In tropical and subtropical regions, several geographical sectors do not present defined seasons; but in the seasonal tropics, the annual wet and dry seasons are recognized and tracked. A calendar year is an approximation of the number of days of the Earth's orbital period, as counted in a given calendar. The Gregorian calendar, or modern calendar, presents its calendar year to be either a common year of 365 days or a leap year of 366 days, as do the Julian calendars. For the Gregorian calendar, the average length of the calendar year (t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pedigree Collapse
In genealogy, pedigree collapse describes how reproduction between two individuals who share an ancestor causes the number of distinct ancestors in the family tree of their offspring to be smaller than it could otherwise be. Robert C. Gunderson coined the term; synonyms include implex and the German ''Ahnenschwund'' (loosely translated: "loss of lineage"). Overview Without pedigree collapse, a person's ancestor tree is a binary tree, formed by the person, the parents (2), the grandparents (4), great-grandparents (8), and so on. However, the number of individuals in such a tree grows exponentially and will eventually become impossibly high. For example, a single individual alive today would, over 30 generations going back to the High Middle Ages, have 230 or roughly 1,000 million ancestors, more than the total world population at the time. This paradox is explained by shared ancestors, referred to as pedigree collapse. Instead of consisting of all different individuals, a tree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Recent African Origin
In paleoanthropology, the recent African origin of modern humans, also called the "Out of Africa" theory (OOA), recent single-origin hypothesis (RSOH), replacement hypothesis, or recent African origin model (RAO), is the dominant model of the geographic origin and Early human migrations, early migration of anatomically modern humans (''Homo sapiens''). It follows the early expansions of hominins out of Africa, accomplished by ''Homo erectus'' and then ''Homo neanderthalensis''. The model proposes a "single origin" of ''Homo sapiens'' in the taxonomic sense, precluding parallel evolution in other regions of traits considered anatomically modern humans, anatomically modern, but not precluding multiple Archaic human admixture with modern humans, admixture between ''H. sapiens'' and archaic humans in Europe and Asia. ''H. sapiens'' most likely developed in the Horn of Africa between 300,000 and 200,000 years ago, although an alternative hypothesis argues that diverse morphological ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bonobo
The bonobo (; ''Pan paniscus''), also historically called the pygmy chimpanzee and less often the dwarf chimpanzee or gracile chimpanzee, is an endangered great ape and one of the two species making up the genus '' Pan,'' the other being the common chimpanzee (''Pan troglodytes''). While bonobos are now recognized as a distinct species in their own right, they were initially thought to be a subspecies of chimpanzee (''Pan troglodytes)'' due to the physical similarities between the two species. Taxonomically, the members of the chimpanzee/bonobo subtribe Panina (composed entirely by the genus '' Pan'') are collectively termed ''panins''. The bonobo is distinguished by relatively long legs, pink lips, dark face, tail-tuft through adulthood, and parted long hair on its head. The bonobo is found in a area of the Congo Basin in the Democratic Republic of the Congo, Central Africa. The species is frugivorous and inhabits primary and secondary forests, including seasonally inundated sw ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Common Chimpanzee
The chimpanzee (''Pan troglodytes''), also known as simply the chimp, is a species of Hominidae, great ape native to the forest and savannah of tropical Africa. It has four confirmed subspecies and a fifth proposed subspecies. When its close relative the bonobo was more commonly known as the pygmy chimpanzee, this species was often called the common chimpanzee or the robust chimpanzee. The chimpanzee and the bonobo are the only species in the genus Pan (genus), ''Pan''. Evidence from fossils and DNA sequencing shows that ''Pan'' is a sister taxon to the Human evolution, human lineage and is humans' closest living relative. The chimpanzee is covered in coarse black hair, but has a bare face, fingers, toes, palms of the hands, and soles of the feet. It is larger and more Robustness (morphology), robust than the bonobo, weighing for males and for females and standing . The chimpanzee lives in groups that range in size from 15 to 150 members, although individuals travel and forag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pan (genus)
The genus ''Pan'' consists of two extant species: the chimpanzee and the bonobo. Taxonomically, these two ape species are collectively termed panins; however, both species are more commonly referred to collectively using the generalized term chimpanzees, or chimps. Together with humans, gorillas, and orangutans they are part of the family Hominidae (the great apes, or ''hominids''). Native to sub-Saharan Africa, chimpanzees and bonobos are currently both found in the Congo jungle, while only the chimpanzee is also found further north in West Africa. Both species are listed as endangered species, endangered on the IUCN Red List of Threatened Species, and in 2017 the Convention on Migratory Species selected the chimpanzee for special protection. Chimpanzee and bonobo: comparison The chimpanzee (''P. troglodytes'') who lives north of the Congo River, and the bonobo (''P. paniscus'') who lives south of it, were once considered to be the same species, but since 1928 they have b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gorilla
Gorillas are herbivorous, predominantly ground-dwelling great apes that inhabit the tropical forests of equatorial Africa. The genus ''Gorilla'' is divided into two species: the eastern gorilla and the western gorilla, and either four or five subspecies. The DNA of gorillas is highly similar to that of humans, from 95 to 99% depending on what is included, and they are the next closest living relatives to humans after chimpanzees and bonobos. Gorillas are the largest living primates, reaching heights between 1.25 and 1.8 metres, weights between 100 and 270 kg, and arm spans up to 2.6 metres, depending on species and sex. They tend to live in troops, with the leader being called a silverback. The Eastern gorilla is distinguished from the Western by darker fur colour and some other minor morphological differences. Gorillas tend to live 35–40 years in the wild. The oldest gorilla known is Fatou (b. 1957), who is still alive at the advanced age of 65 years. Gorillas' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nuclear DNA
Nuclear DNA (nDNA), or nuclear deoxyribonucleic acid, is the DNA contained within each cell nucleus of a eukaryotic organism. It encodes for the majority of the genome in eukaryotes, with mitochondrial DNA and plastid DNA coding for the rest. It adheres to Mendelian inheritance, with information coming from two parents, one male and one female—rather than matrilineally (through the mother) as in mitochondrial DNA. Structure Nuclear DNA is a nucleic acid, a polymeric biomolecule or biopolymer, found in the nucleus of eukaryotic cells. Its structure is a double helix, with two strands wound around each other, a structure first described by Francis Crick and James D. Watson (1953) using data collected by Rosalind Franklin. Each strand is a long polymer chain of repeating nucleotides. Each nucleotide is composed of a five-carbon sugar, a phosphate group, and an organic base. Nucleotides are distinguished by their bases: purines, large bases that include adenine and guanine; and pyr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mutation
In biology, a mutation is an alteration in the nucleic acid sequence of the genome of an organism, virus, or extrachromosomal DNA. Viral genomes contain either DNA or RNA. Mutations result from errors during DNA or viral replication, mitosis, or meiosis or other types of damage to DNA (such as pyrimidine dimers caused by exposure to ultraviolet radiation), which then may undergo error-prone repair (especially microhomology-mediated end joining), cause an error during other forms of repair, or cause an error during replication (translesion synthesis). Mutations may also result from insertion or deletion of segments of DNA due to mobile genetic elements. Mutations may or may not produce detectable changes in the observable characteristics (phenotype) of an organism. Mutations play a part in both normal and abnormal biological processes including: evolution, cancer, and the development of the immune system, including junctional diversity. Mutation is the ultimate source o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rebecca L
Rebecca, ; Syriac: , ) from the Hebrew (lit., 'connection'), from Semitic root , 'to tie, couple or join', 'to secure', or 'to snare') () appears in the Hebrew Bible as the wife of Isaac and the mother of Jacob and Esau. According to biblical tradition, Rebecca's father was Bethuel the Aramean from Paddan Aram, also called Aram-Naharaim. Rebecca's brother was Laban the Aramean, and she was the granddaughter of Milcah and Nahor, the brother of Abraham. Rebecca and Isaac were one of the four couples that some believe are buried in the Cave of the Patriarchs, the other three being Adam and Eve, Abraham and Sarah, and Jacob and Leah. Early life After the Binding of Isaac, Sarah died. After taking care of her burial, Abraham went about finding a wife for his son Isaac, who was already 37 years old. He commanded his servant (whom the Torah commentators identify as Eliezer of Damascus) to journey to his birthplace of Aram Naharaim to select a bride from his own family, rather than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mark Stoneking
Mark Stoneking (born 1 August 1956) is a geneticist currently working as the Group Leader of the Max Planck Institute for Evolutionary Anthropology, of Max Planck Gesellschaft at Leipzig, and Honorary Professor of Biological Anthropology, University of Leipzig, Leipzig, Germany. He works in the field of human evolution, especially the genetic evolution, origin and dispersal of modern humans. He, along with his doctoral advisor Allan Wilson and a fellow researcher Rebecca L. Cann, contributed to the Out of Africa Theory in 1987 by introducing the concept of Mitochondrial Eve, a hypothetical common mother of all living humans based on mitochondrial DNA. Education Stoneking studied an undergraduate course in anthropology from 1974 at the University of Oregon, United States, from where he obtained a Bachelor of Arts (B.A.) degree in 1977. He shifted to the Pennsylvania State University to obtain MS in genetics in 1979, and subsequently a similar master's degree from University of Wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allan Wilson (biologist)
Allan Charles Wilson FRS AAA&S (18 October 1934 – 21 July 1991) was a professor of biochemistry at the University of California, Berkeley, a pioneer in the use of molecular approaches to understand evolutionary change and reconstruct phylogenies, and a revolutionary contributor to the study of human evolution. He was one of the most controversial figures in post-war biology; his work attracted a great deal of attention both from within and outside the academic world. He is the only New Zealander to have won the MacArthur Fellowship. He is best known for experimental demonstration of the concept of the molecular clock (with his doctoral student Vincent Sarich), which was theoretically postulated by Linus Pauling and Emile Zuckerkandl, revolutionary insights into the nature of the molecular anthropology of higher primates and human evolution, and the so-called Mitochondrial Eve hypothesis (with his doctoral students Rebecca L. Cann and Mark Stoneking). Early life and educatio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
