Population genetics

Population genetics is a subfield of genetics that deals with genetic differences within and between populations, is a part of evolutionary biology. Studies in this branch of biology examine such phenomena as adaptation and population structure. Population genetics was a vital ingredient in the emergence of the modern evolutionary synthesis, its primary founders were Sewall Wright, J. B. S. Haldane and Ronald Fisher, who laid the foundations for the related discipline of quantitative genetics. Traditionally a mathematical discipline, modern population genetics encompasses theoretical and field work. Population genetic models are used both for statistical inference from DNA sequence data and for proof/disproof of concept. What sets population genetics apart today from newer, more phenotypic approaches to modelling evolution, such as evolutionary game theory and adaptive dynamics, is its emphasis on genetic phenomena as dominance and the degree to which genetic recombination breaks up linkage disequilibrium.

This makes it appropriate for comparison to population genomics data. Population genetics began as a reconciliation of Mendelian biostatistics models. Natural selection will only cause evolution. Before the discovery of Mendelian genetics, one common hypothesis was blending inheritance, but with blending inheritance, genetic variance would be lost, making evolution by natural or sexual selection implausible. The Hardy–Weinberg principle provides the solution to how variation is maintained in a population with Mendelian inheritance. According to this principle, the frequencies of alleles will remain constant in the absence of selection, mutation and genetic drift; the next key step was the work of statistician Ronald Fisher. In a series of papers starting in 1918 and culminating in his 1930 book The Genetical Theory of Natural Selection, Fisher showed that the continuous variation measured by the biometricians could be produced by the combined action of many discrete genes, that natural selection could change allele frequencies in a population, resulting in evolution.

In a series of papers beginning in 1924, another British geneticist, J. B. S. Haldane, worked out the mathematics of allele frequency change at a single gene locus under a broad range of conditions. Haldane applied statistical analysis to real-world examples of natural selection, such as peppered moth evolution and industrial melanism, showed that selection coefficients could be larger than Fisher assumed, leading to more rapid adaptive evolution as a camouflage strategy following increased pollution; the American biologist Sewall Wright, who had a background in animal breeding experiments, focused on combinations of interacting genes, the effects of inbreeding on small isolated populations that exhibited genetic drift. In 1932 Wright introduced the concept of an adaptive landscape and argued that genetic drift and inbreeding could drive a small, isolated sub-population away from an adaptive peak, allowing natural selection to drive it towards different adaptive peaks; the work of Fisher and Wright founded the discipline of population genetics.

This integrated natural selection with Mendelian genetics, the critical first step in developing a unified theory of how evolution worked. John Maynard Smith was Haldane's pupil, whilst W. D. Hamilton was influenced by the writings of Fisher; the American George R. Price worked with both Maynard Smith. American Richard Lewontin and Japanese Motoo Kimura were influenced by Wright and Haldane; the mathematics of population genetics were developed as the beginning of the modern synthesis. Authors such as Beatty have asserted that population genetics defines the core of the modern synthesis. For the first few decades of the 20th century, most field naturalists continued to believe that Lamarckism and orthogenesis provided the best explanation for the complexity they observed in the living world. During the modern synthesis, these ideas were purged, only evolutionary causes that could be expressed in the mathematical framework of population genetics were retained. Consensus was reached as to which evolutionary factors might influence evolution, but not as to the relative importance of the various factors.

Theodosius Dobzhansky, a postdoctoral worker in T. H. Morgan's lab, had been influenced by the work on genetic diversity by Russian geneticists such as Sergei Chetverikov, he helped to bridge the divide between the foundations of microevolution developed by the population geneticists and the patterns of macroevolution observed by field biologists, with his 1937 book Genetics and the Origin of Species. Dobzhansky examined the genetic diversity of wild populations and showed that, contrary to the assumptions of the population geneticists, these populations had large amounts of genetic diversity, with marked differences between sub-populations; the book took the mathematical work of the population geneticists and put it into a more accessible form. Many more biologists were influenced by population genetics via Dobzhansky than were able to read the mathematical works in the original. In Great Britain E. B. Ford, the pioneer of ecological genetics, continued throughout the 1930s and 1940s to empirically demonstrate the power of selection due to ecological factors including the ability to maintain genetic diversity through genetic polymorphisms such as human blood types.

Ford's work, in collaboration with Fisher, contributed to a shift in emphasis during the course of the modern synthesis towards natural selection as the dominant force. The original, modern synthesis view of population genetics assumes that

Kyokutenzan Takeshi

Kyokutenzan Takeshi is a former professional sumo wrestler from Ulaanbaatar, one of the first Mongolians to join the sport in Japan. He did not manage to reach the top two divisions, but was regarded as a kind of mentor and father figure by younger Mongolian wrestlers who followed him, such as Hakuhō and Harumafuji. In 2005, he obtained Japanese citizenship, but he left sumo upon his retirement in November 2007, moving to Germany with his family to run a business. Kyokutenzan joined sumo in March 1992 at the same time as his more famous Mongolian colleagues Kyokushūzan and Kyokutenhō, part of the first group of Mongolians to join the sport professionally, but unlike them he never reached sekitori status; this was due to an inability to put on weight, to injuries. He served as a tsukebito, or personal attendant, to Kyokutenhō, was an importance influence on other Mongolian rikishi. During his early days in sumo, when five of the six Mongolians in Ōshima stable ran away due to homesickness and the hardship of training, sought refuge in the Mongolian embassy, Kyokutenzan was the only one who remained and he persuaded his countrymen to return.

The importance of this action was recognized by Futagoyama Oyakata, the former ōzeki and father of Takanohana and Wakanohana, who commented that otherwise the subsequent line of successful Mongolian wrestlers in sumo might never have emerged. During the January 2007 tournament Kyokutenzan attracted criticism over the amount of time he was spending in the two dressing rooms in which the wrestlers prepare for their bouts, he was interviewed by the Japan Sumo Association as part of their investigation of alleged match-fixing involving yokozuna Asashōryū. Kyokutenzan responded by saying he was just giving advice to Mongolian junior wrestlers, declaring, "I have never known of any match-fixing."Kyokutenzan retired from professional sumo at the end of the 2007 Kyushu tournament. His retirement ceremony was held in December with Hakuhō and Asashōryū amongst the attendees as well as Kyokushūzan and Kyokutenhō. Kyuokutenzan moved to Germany with his wife, his first child, a girl, was born in May 2008.

Glossary of sumo terms List of non-Japanese sumo wrestlers List of past sumo wrestlers Kyokutenzan Takeshi's official biography at the Grand Sumo Homepage

Wisdom (film)

Wisdom is a 1986 American romantic crime film written and directed by its star Emilio Estevez in his filmmaking debut. The film stars Demi Moore, along with Tom Skerritt and Veronica Cartwright as Estevez's parents; the ending credits song is "Home Again" by the score by Danny Elfman. The film is dedicated to the memory of Henry Proach, a good friend of Estevez, who appears in the picture. John Wisdom is a young man just out of college. On the night of his high school graduation, he stole a car. With a grand theft auto conviction he is branded a felon and as a result can not hold down a decent job. Seeing no future for himself, Wisdom takes a left turn: he decides to become a criminal "for the people", evocative of Robin Hood. After seeing news reports about impoverished farmers and working class people being sent to the bank to pay ownership debts, Wisdom goes on a bank robbing spree with his girlfriend, Karen Simmons. With the FBI after them, things take a turn for the worse when a panicky Karen kills a local sheriff.

She and Wisdom make a run for the Canada–United States border, but when Karen is shot by a police helicopter, Wisdom leaves her in the care of some high school students and their teacher. He is surrounded by police and federal agents at a college football field; as Wisdom appears to be reaching for his gun, he dies. John wakes up, he emerges from proceeds to get ready for his job interview. His entire story has been a daydream. Emilio Estevez as John Wisdom Demi Moore as Karen Simmons Tom Skerritt as Lloyd Wisdom Veronica Cartwright as Samantha Wisdom William Allen Young as Agent Williamson Richard Minchenberg as Agent Cooper Ernie Brown as Bill, Motel manager Charlie Sheen as City Burger manager Brenda Medcalf as Girl on bike Estevez says the idea for the film "started as just the title. I thought. Just'Wisdom' across the screen."He wrote the first draft in three weeks. Wisdom became the surname of the lead character. Estevez says Wisdom is "without a place in society... He becomes a criminal because he feels it's the only thing society has left him to do."Estevez added at the film was "about two people - their relationship and their discoveries.

Those discoveries leave Wisdom not only wanted dead or alive in five states, but a modern-day folk hero."In October 1985 David Begelman's Gladden Entertainment announced it had signed a deal with the 23 year old Estevez to write and direct Wisdom. Estevez had written That Was Then This is Now. Begelman had been in charge of Columbia, MGM, during which time he gave Walter Hill, Barry Levinson and Richard Benjamin their first directing jobs. Comparisons were made with Orson Welles, 24 when he wrote and directed Citizen Kane. Estevez said "if they promote Wisdom as this most phenomenal thing that hasn't happened since Orson Welles, I'm going to get hit.""I have a kind of nihilistic point of view," he added. "I'm into making films that are not fluff. When you deal in reality, you're dealing with a lot of serious problems. We could be being vaporized by nuclear weapons by accidentally. That's reality... Life does not end ever after."The female lead went to Demi Moore, Estevez's fiancée."I'm not going to sit here and say it was the most positive professional move for me when I made that picture," she said later.

"Of course, doing it was based on my feelings for him and my desire to share it with him. It was special. I was around from the day Emilio wrote the first page. I would read every page, we would talk; the attachment to the project was real."The Gladden Entertainment Company suggested Robert Wise be hired to work as "executive director" and Estevez agreed. Wise said, "I was there to be an aid to him if he wanted to discuss something or whether he felt this kind of angle or editing standpoint was a good one, whether the different angles in a scene were enough coverage. I didn't step in when he was staging a scene. If I saw something that bothered me, I would get him aside and say,'Be careful of this or watch for that. Be careful, I think you have her looking the wrong way in this shot.' Technical things. We would discuss the pacing of scenes, and that would be it."The film was finished $200,000 under budget and a day ahead of schedule. It was one of the first film scores from Danny Elfman."In a way, it's a subversive film," Estevez said.

"A lot of people are angered by the message it gives the kids: If you want something changed pick up a gun and change it. But if they stay until the end, they'll realize. I'm going to take a beating on this one. "I can see myself getting my feet wet as a director, there's a choppiness, an awkwardness to it. It's not relaxed. I made the movie first for myself, I think just getting it done is an accomplishment. I fought my battle in just getting it done, being the youngest person to get it done. Not that I set out to break any kind of record or anything, or to prove to anybody that I could do it." The film received negative reviews from critics: Leonard Maltin considered it "wretchedly scripted, with one of the most self-defeating wrap-ups you'll see." Estevez said the film "was a disappointing experience - the outcome of it. I shouldn't say disappointing. I should say devastating - the response. I tell you what: It was not a great film, but it was a good film, and I believe that now... I