Miller

Miller

[mil-er]
Miller, Alfred Jacob, 1810-74, American artist, b. Baltimore, studied under Thomas Sully and in Europe. In 1837 he joined an expedition to the American West and was probably the first artist to depict the Rocky Mts. On that trip he produced his most important works, chiefly studies of Native American and frontier life, valuable for their documentary detail. These sketches and watercolors were entirely forgotten for nearly a century until they were rediscovered in a storeroom of the Peale Museum, Baltimore.
Miller, Arthur, 1915-2005, American dramatist, b. New York City, grad. Univ. of Michigan, 1938. One of America's most distinguished playwrights, he has been hailed as the finest realist of the 20th-century stage. Miller's plays are, above all, concerned with morality as they reflect the individual's response to the manifold pressures exerted by the forces of family and society. Recurring themes of his major works involve the overwhelming importance of personal and social responsibility and the moral corruption that results from betraying the dictates of conscience.

Miller's masterpiece, Death of a Salesman (1949; Pulitzer Prize), is the story of a salesman betrayed by his own hollow values and those of American society. The Crucible (1953) is both a dynamic dramatization of the 17th-century Salem witch trials and a parable about the United States in the McCarthy era (see McCarthy, Joseph Raymond); it has been his most frequently produced work. In A View from the Bridge (1955; Pulitzer Prize) Miller studies a Sicilian-American longshoreman whose unacknowledged lust for his niece destroys him and his family. Miller's tumultuous life with his second wife, Marilyn Monroe, to whom he was married from 1956 to 1961, is fictionalized in his After the Fall (1964), and a barely disguised version of the glamorous but troubled actress also appears in his last play, Finishing the Picture (2004).

Miller's other plays include The Man Who Had All the Luck (1940), All My Sons (1947), Incident at Vichy (1965), The Price (1968), The Creation of the World and Other Business (1972), The American Clock (1980), The Ride down Mount Morgan (1991), Broken Glass (1994), and Resurrection Blues (2002). He also wrote the screenplay for The Misfits (1961); the television dramas Playing for Time (1980) and Clara (1991); a novel, Focus (1945); and two books of short stories (1967, 2007). Miller's The Theater Essays (1971, rev. ed. 1996) is a collection of writings about the craft of playwriting and the nature of modern tragedy, and Echoes down the Corridor (2000) is a collection of essays (1944-2000), many of them autobiographical. He collaborated with his third wife, the photographer Inge Morath (1923-2002), on several books; their In Russia (1969) is a study of the Soviet Union.

See his autobiography, Timebends (1987); M. C. Roudane, Conversations with Arthur Miller (1987), S. Centola, Arthur Miller in Conversation (1993), M. Gussow, Conversations with Miller (2002); biographies by M. Gottfried (2003) and C. Bigsby (2008); studies by B. Nelson (1970), R. Hayman (1972), J. J. Martine, ed. (1979), D. Welland (1979, repr. 1985), L. Moss (rev. ed. 1980), H. Bloom, ed. (1987), J. Schlueter and J. K. Flanagan (1987), N. Carson (1988), P. Singh (1990), S. R. Centola, ed. (1995), A. Griffin (1996), T. Otten (2002), C. Bigsby (2004), and E. Brater, ed. (2005).

Miller, Cincinnatus Heine or Hiner: see Miller, Joaquin.
Miller, George Abram, 1863-1951, American mathematician, b. Lehigh co., Pa., grad. Muhlenberg College (B.A., 1887), Ph.D. Cumberland Univ., 1893. He was professor at the Univ. of Illinois (1907-31). His chief work was in the theory of groups of finite order, in the development and use of determinants, and in the history of mathematics.
Miller, Glenn (Alton Glenn Miller), 1904-44, American jazz trombonist, bandleader, and composer, b. Clarinda, Iowa. Playing in Ben Pollack's band by 1927, he was a freelance musician in New York City during the 1930s. He formed his own big band in 1938, and it soon became one of swing's most popular groups, known for its sweet sound, smooth arrangements, and harmonious vocals. Among his many hits were "Moonlight Serenade" (his theme), "In the Mood," and "Tuxedo Junction." At the height of his fame Miller appeared in two Hollywood movies. During World War II he joined (1942) the military, and entertained the troops as leader of the U.S. Air Force band. While flying from England to Paris his plane disappeared, and Miller, who was never found, was hailed as a hero.

See G. T. Simon, Glen Miller and His Orchestra (1974, repr. 1980); J. Green, Glenn Miller and the Age of Swing (1976); P. Tanner and B. Cox, "Every Night Was New Year's Eve": On the Road with Glenn Miller (1992); discography by C. Garrod (1995).

Miller, Henry, 1891-1980, American author, b. New York City. Miller sought to reestablish the freedom to live without the conventional restraints of civilization. His books are potpourris of sexual description, quasi-philosophical speculation, reflection on literature and society, surrealistic imaginings, and autobiographical incident. After living in Paris in the 1930s, he returned to the United States and settled in Big Sur, Calif. Miller's first two works, Tropic of Cancer (Paris, 1934) and Tropic of Capricorn (Paris, 1939), were denied publication in the U.S. until the early 1960s because of alleged obscenity. The Colossus of Maroussi (1941), a travel book of modern Greece, is considered by some critics his best work. His other writings include the Rosy Crucifixion Trilogy—Sexus (1949), Plexus (1953), and Nexus (1960). In 1976 Norman Mailer edited a selection of Miller's writings, Genius and Lust.

See his autobiography My Life and Times (1972); memoir by K. Winslow (1986). See biographies by J. Miller (1978) and R. Ferguson (1991); W. A. Gordon, The Mind and Art of Henry Miller (1967), E. B. Mitchell, ed., Henry Miller (1971), and N. Mailer, Black Messiah (1981).

Miller, Joaquin, pseud. of Cincinnatus Heine (or Hiner) Miller, 1839?-1913, American poet, b. Liberty, Ind. In 1852 his family moved to frontier Oregon. He lived in gold-mining camps, later with Native Americans, and was in turn an express rider, an editor, and an Oregon judge. His first two volumes of poems, Specimens (1868) and Joaquin et al. (1869), contained energetic, rhetorical celebrations of frontier life. They brought him only local acclaim, but in England, where he went next, his colorful personality, his dramatic Western costume, and his Songs of the Sierras (1871) made him famous as a frontier poet. See his autobiography (1898; ed. by S. G. Firman, 1930).
Miller, Jonathan Wolfe, 1934-, English director, actor, writer, and physician. Forsaking medicine, Miller made his first London (1961) and New York (1962) stage appearances as coauthor and actor in the zany satirical revue Beyond the Fringe. Miller directed The Old Glory in New York and Danton's Death, The School for Scandal, and The Merchant of Venice for the National Theatre. He has written and directed radio shows, written theater and art criticism, and in 1969 toured the United States as director of the Oxford and Cambridge Shakespeare Company. Since 1974 he has directed operas, including the highly successful 1984 production of Verdi's Rigoletto for the English National Opera and his 1998 staging of Mozart's Marriage of Figaro (1998). He also wrote and hosted the television series The Body in Question (1978) and Madness (1991). As a director, he eschews elaborate productions and encourages his actors to attempt new interpretations of their roles.
Miller, Marvin Julian, 1917-, U.S. labor leader, b. Bronx, N.Y., grad. Miami Univ. of Ohio (B.S., 1938). He worked at the National War Labor Board during World War II, and later at the International Association of Machinists (1947-50) and United Steel Workers (1950-66). From 1966 to 1983 he was executive director of the Major League Baseball Players Association (MLBPA), a post in which he radically altered player-owner relations in baseball. During his tenure, players achieved increased minimum salaries, the first collective bargaining agreement in professional sports, pension plans, arbitration rights, and the right to free agency, which led to huge increases in compensation. Miller also led the MLBPA in the baseball strikes of 1972 (the first in professional baseball) and 1981. The successes of the MLBPA under Miller set new standards for players' rights and encouraged unionization in other professional sports.

See his A Whole Different Ball Game (1991, repr. 2004).

Miller, Merton H., 1923-2000, American economist, grad. Harvard, 1943, Ph.D. Johns Hopkins, 1952. A professor at Carnegie-Mellon Univ. (1953-61) and the Univ. of Chicago (1961-93), he developed a theory with Franco Modigliani that seeks a relationship between a company's capital-asset structure and its market value. For his work, he shared the 1990 Nobel Memorial Prize in Economic Sciences with William Sharpe and Harry Markowitz.
Miller, Perry, 1905-63, U.S. historian, b. Chicago. He received his Ph.D. from the Univ. of Chicago in 1931 and taught at Harvard from 1931 until his death. A towering figure in the field of American intellectual history, Miller wrote extensively, especially about colonial New England. In The New England Mind (1939) he argued that the Puritans had a coherent world view firmly rooted in theology and that religion rather than economics was the prime motive behind the settling of New England. Miller's work stimulated a renewed interest in American Puritanism. His other books include Orthodoxy in Massachusetts (1933), From Colony to Province (1953), Errand into the Wilderness (1956), The American Puritans: Their Prose and Poetry (repr. 1982), and intellectual biographies of Jonathan Edwards (1949) and Roger Williams (1953).
Miller, William, 1782-1849, American sectarian leader, b. Pittsfield, Mass. He was the founder of the sect of Second Adventists, sometimes called Millerites. In 1831, convinced from study of the Bible that the prophecies pointed to the second coming of Christ in 1843, he went about spreading his belief among large audiences. Many prepared for the Day of Judgment, and when the year passed without a fulfillment of Miller's prophecy, a date in 1844 was set. In 1845 Miller and his followers founded the Adventist Church.
or owlet moth

Any of the more than 20,000 moth species in the lepidopteran family Noctuidae, common worldwide. Some species have a 1-ft (30-cm) wingspan, the largest of any moth, but most species have a wingspan of 1.5 in. (4 cm) or less. The wings are usually dull-coloured. Both larvae and adults of most species feed at night. Adults feed on fruits, sap, and nectar. The larvae of many species are agricultural pests (e.g., cutworm, bollworm) that feed on foliage and seeds, bore into stems and fruits, and eat or sever roots. A few species prey on scale insects.

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(born July 21, 1934, London, Eng.) British director, writer, and actor. After earning a medical degree at Cambridge University, he made his professional stage debut at the Edinburgh Festival in the hit satirical revue Beyond the Fringe (1960). As a director of plays, he gained notoriety for his controversial interpretations of classic works. His innovative opera productions, such as Pyotr Tchaikovsky's Eugene Onegin, for the English National Opera and other groups have become internationally celebrated. He wrote the BBC medical series The Body in Question (1977) and States of Mind (1982).

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Henry Miller.

(born Dec. 26, 1891, New York, N.Y., U.S.—died June 7, 1980, Pacific Palisades, Calif.) U.S. writer and perennial bohemian. Miller wrote about his Brooklyn, N.Y., childhood in Black Spring (1936). Tropic of Cancer (1934), a monologue about his life as an impoverished expatriate in Paris, and Tropic of Capricorn (1939), which draws on his earlier New York phase, were banned as obscene in the U.S. and Britain until the 1960s. The Air-Conditioned Nightmare (1945) is a critical account of a tour of the U.S. He settled on the California coast, where he became the centre of a colony of admirers and wrote his Rosy Crucifixion trilogy, Sexus, Plexus, and Nexus (U.S. ed., 1965).

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(born March 1, 1904, Clarinda, Iowa, U.S.—died Dec. 16, 1944, at sea) U.S. trombonist and leader of one of the most popular dance bands of the swing era. Miller formed his band in 1937. His music was characterized by the precise execution of arrangements that featured a clarinet doubling the saxophone melody. Broadcasts beginning in 1939 brought the band national exposure and millions of fans. Miller disbanded in 1942 to join the war effort by leading a military band. He was traveling from London to Paris by plane when the craft disappeared and was never recovered. His recordings of numbers such as “Moonlight Sonata,” “Chattanooga Choo-Choo,” “In the Mood,” and “String of Pearls” are classics of the era.

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Arthur Miller, photograph by Inge Morath

(born Oct. 17, 1915, New York, N.Y., U.S.—died Feb. 10, 2005, Roxbury, Conn.) U.S. playwright. He began writing plays while a student at the University of Michigan. His first important play, All My Sons (1947), was followed by his most famous work, Death of a Salesman (1949, Pulitzer Prize), the tragedy of a man destroyed by false values that are in large part the values of his society. Noted for combining social awareness with a searching concern for his characters' inner lives, Miller wrote many other plays, including The Crucible (1953), which uses a plot about the Salem witch trials to attack McCarthyism, A View from the Bridge (1955), After the Fall (1964), The Last Yankee (1992), and Resurrection Blues (2002). He also wrote short stories, essays, and the screenplay for The Misfits (1961), which starred his second wife, Marilyn Monroe.

Learn more about Miller, Arthur with a free trial on Britannica.com.

(born July 21, 1934, London, Eng.) British director, writer, and actor. After earning a medical degree at Cambridge University, he made his professional stage debut at the Edinburgh Festival in the hit satirical revue Beyond the Fringe (1960). As a director of plays, he gained notoriety for his controversial interpretations of classic works. His innovative opera productions, such as Pyotr Tchaikovsky's Eugene Onegin, for the English National Opera and other groups have become internationally celebrated. He wrote the BBC medical series The Body in Question (1977) and States of Mind (1982).

Learn more about Miller, Jonathan (Wolfe) with a free trial on Britannica.com.

Henry Miller.

(born Dec. 26, 1891, New York, N.Y., U.S.—died June 7, 1980, Pacific Palisades, Calif.) U.S. writer and perennial bohemian. Miller wrote about his Brooklyn, N.Y., childhood in Black Spring (1936). Tropic of Cancer (1934), a monologue about his life as an impoverished expatriate in Paris, and Tropic of Capricorn (1939), which draws on his earlier New York phase, were banned as obscene in the U.S. and Britain until the 1960s. The Air-Conditioned Nightmare (1945) is a critical account of a tour of the U.S. He settled on the California coast, where he became the centre of a colony of admirers and wrote his Rosy Crucifixion trilogy, Sexus, Plexus, and Nexus (U.S. ed., 1965).

Learn more about Miller, Henry (Valentine) with a free trial on Britannica.com.

Ernest Hemingway, photograph by Yousuf Karsh, 1959.

(born July 21, 1899, Cicero [now in Oak Park], Ill., U.S.—died July 2, 1961, Ketchum, Idaho) U.S. writer. He began work as a journalist after high school. He was wounded while serving as an ambulance driver in World War I. One of a well-known group of expatriate writers in Paris, he soon embarked on a life of travel, skiing, fishing, and hunting that would be reflected in his work. His story collection In Our Time (1925) was followed by the novel The Sun Also Rises (1926). Later novels include A Farewell to Arms (1929) and To Have and Have Not (1937). His lifelong love for Spain (including a fascination with bullfighting) led to his working as a correspondent during the Spanish Civil War, which resulted in the novel For Whom the Bell Tolls (1940). Other short-story collections include Men Without Women (1927), Winner Take Nothing (1933), and The Fifth Column (1938). He lived primarily in Cuba from circa 1940, the locale of his novella The Old Man and the Sea (1952, Pulitzer Prize). He was awarded the Nobel Prize for Literature in 1954. He left Cuba shortly after its 1959 revolution; a year later, depressed and ill, he shot himself. The succinct and concentrated prose style of his early works strongly influenced many British and American writers for decades.

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Ernest Hemingway, photograph by Yousuf Karsh, 1959.

(born July 21, 1899, Cicero [now in Oak Park], Ill., U.S.—died July 2, 1961, Ketchum, Idaho) U.S. writer. He began work as a journalist after high school. He was wounded while serving as an ambulance driver in World War I. One of a well-known group of expatriate writers in Paris, he soon embarked on a life of travel, skiing, fishing, and hunting that would be reflected in his work. His story collection In Our Time (1925) was followed by the novel The Sun Also Rises (1926). Later novels include A Farewell to Arms (1929) and To Have and Have Not (1937). His lifelong love for Spain (including a fascination with bullfighting) led to his working as a correspondent during the Spanish Civil War, which resulted in the novel For Whom the Bell Tolls (1940). Other short-story collections include Men Without Women (1927), Winner Take Nothing (1933), and The Fifth Column (1938). He lived primarily in Cuba from circa 1940, the locale of his novella The Old Man and the Sea (1952, Pulitzer Prize). He was awarded the Nobel Prize for Literature in 1954. He left Cuba shortly after its 1959 revolution; a year later, depressed and ill, he shot himself. The succinct and concentrated prose style of his early works strongly influenced many British and American writers for decades.

Learn more about Hemingway, Ernest (Miller) with a free trial on Britannica.com.

(born May 17, 1873, Abingdon, Berkshire, Eng.—died June 17, 1957, Beckenham, Kent) English novelist. From age 17 she engaged in teaching, clerical work, and journalism. For much of her life she worked on her sequence novel Pilgrimage, comprising 13 volumes beginning with Pointed Roofs (1915). The final volume, March Moonlight, was published a decade after her death. A sensitive autobiographical account of a woman's developing consciousness, it was a pioneering work in stream-of-consciousness fiction.

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Arthur Miller, photograph by Inge Morath

(born Oct. 17, 1915, New York, N.Y., U.S.—died Feb. 10, 2005, Roxbury, Conn.) U.S. playwright. He began writing plays while a student at the University of Michigan. His first important play, All My Sons (1947), was followed by his most famous work, Death of a Salesman (1949, Pulitzer Prize), the tragedy of a man destroyed by false values that are in large part the values of his society. Noted for combining social awareness with a searching concern for his characters' inner lives, Miller wrote many other plays, including The Crucible (1953), which uses a plot about the Salem witch trials to attack McCarthyism, A View from the Bridge (1955), After the Fall (1964), The Last Yankee (1992), and Resurrection Blues (2002). He also wrote short stories, essays, and the screenplay for The Misfits (1961), which starred his second wife, Marilyn Monroe.

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The Miller-Urey experiment (or Urey-Miller experiment) was an experiment that simulated hypothetical conditions present on the early Earth and tested for the occurrence of chemical evolution. Specifically, the experiment tested Oparin and Haldane's hypothesis that conditions on the primitive Earth favored chemical reactions that synthesized organic compounds from inorganic precursors. Considered to be the classic experiment on the origin of life, it was conducted in 1953 by Stanley L. Miller and Harold C. Urey at the University of Chicago.

Experiment and interpretation

The experiment used water (H2O), methane (CH4), ammonia (NH3) and hydrogen (H2). The chemicals were all sealed inside a sterile array of glass tubes and flasks connected together in a loop, with one flask half-full of liquid water and another flask containing a pair of electrodes. The liquid water was heated to induce evaporation, sparks were fired between the electrodes to simulate lightning through the atmosphere and water vapor, and then the atmosphere was cooled again so that the water could condense and trickle back into the first flask in a continuous cycle.

At the end of one week of continuous operation Miller and Urey observed that as much as 10-15% of the carbon within the system was now in the form of organic compounds. Two percent of the carbon had formed amino acids that are used to make proteins in living cells, with glycine as the most abundant. Sugars, lipids, and some of the building blocks for nucleic acids were also formed.

In an interview, Stanley Miller stated: "Just turning on the spark in a basic pre-biotic experiment will yield 11 out of 20 amino acids."

As observed in all consequent experiments, both left-handed (L) and right-handed (D) optical isomers were created in a racemic mixture.

Other experiments

This experiment inspired many experiments in a similar vein. In 1961, Joan Oró found that amino acids could be made from hydrogen cyanide (HCN) and ammonia in a water solution. He also found that his experiment produced a large amount of the nucleotide base adenine. Experiments conducted later showed that the other RNA and DNA bases could be obtained through simulated prebiotic chemistry with a reducing atmosphere.

There also had been similar electric discharge experiments related to the origin of life contemporaneous with Miller-Urey. An article in The New York Times (March 8, 1953:E9), titled "Looking Back Two Billion Years" describes the work of Wollman (William) M. MacNevin at Ohio State University, before the Miller Science paper was published in May 1953. MacNevin was passing 100,000 volt sparks through methane and water vapor and produced "resinous solids" that were "too complex for analysis." The article describes other early earth experiments being done by MacNevin. It is not clear if he ever published any of these results in the primary scientific literature.

K. A. Wilde submitted a paper to Science on December 15, 1952, before Miller submitted his paper to the same journal on February 14, 1953. Wilde's paper was published on July 10, 1953. Wilde only used voltages up to 600 V on a binary mixture of carbon dioxide and water in a flow system. He only observed small amounts of carbon dioxide reduction to carbon monoxide and no other significant reduction products or newly formed carbon compounds.

More recent experiments by chemist Jeffrey Bada at Scripps Institution of Oceanography, La Jolla, Calif. were similar to those performed by Miller. However, Bada noted that in current models of early Earth conditions carbon dioxide and nitrogen create nitrites, which destroy amino acids as fast as they form. However, the early Earth may have had significant amounts of iron and carbonate minerals able to neutralize the effects of the nitrites. When Bada performed the Miller-type experiment with the addition of iron and carbonate minerals, the products were rich in amino acids. This suggests the origin of significant amounts of amino acids may have occurred on Earth even with an atmosphere containing carbon dioxide and nitrogen.

In 2006 another experiment showed that a thick organic haze might have blanketed Early Earth. An organic haze can form over a wide range of methane and carbon dioxide concentrations, believed to be present in the atmosphere of Early Earth. After forming, these organic molecules would have floated down all over the Earth, allowing life to flourish globally.

Earth's early atmosphere

Some evidence suggests that Earth's original atmosphere might have contained less of the reducing molecules than was thought at the time of Miller-Urey experiment. There is abundant evidence of major volcanic eruptions 4 billion years ago, which would have released carbon dioxide, nitrogen, hydrogen sulfide, and sulfur dioxide into the atmosphere. Experiments using these gases in addition to the ones in the original Miller-Urey experiment have produced more diverse molecules. Although the experiment created a mixture that was racemic (containing both L, D enantiomers), experiments since have shown that "when made from scratch in the lab the two versions are equally likely to appear, but in nature, L amino acids dominate. Other experiments have confirmed disproportionate amounts of L or D oriented enantiomers are possible.

Originally it was thought that the primitive secondary atmosphere contained mostly NH3 and CH4. However, it is likely that most of the atmospheric carbon was CO2 with perhaps some CO and the nitrogen mostly N2. In practice gas mixtures containing CO, CO2, N2, etc. give much the same products as those containing CH4 and NH3 so long as there is no O2. The H atoms come mostly from water vapor. In fact, in order to generate aromatic amino acids under primitive earth conditions it is necessary to use less hydrogen-rich gaseous mixtures. Most of the natural amino acids, hydroxyacids, purines, pyrimidines, and sugars have been produced in variants of the Miller experiment.

More recent results may question these conclusions. The University of Waterloo and University of Colorado conducted simulations in 2005 that indicated that the early atmosphere of Earth could have contained up to 40 percent hydrogen — implying a much more hospitable environment for the formation of prebiotic organic molecules. The escape of hydrogen from Earth's atmosphere into space may have occurred at only one percent of the rate previously believed based on revised estimates of the upper atmosphere's temperature. One of the authors, Owen Toon notes: "In this new scenario, organics can be produced efficiently in the early atmosphere, leading us back to the organic-rich soup-in-the-ocean concept... I think this study makes the experiments by Miller and others relevant again." Outgassing calculations using a chondritic model for the early earth complement the Waterloo/Colorado results in re-establishing the importance of the Miller-Urey experiment.

Although lightning storms are thought to have been very common in the primordial atmosphere, they are not thought to have been as common as the amount of electricity used by the Miller-Urey experiment implied. These factors suggest that much lower concentrations of biochemicals would have been produced on Earth than was originally predicted (although the time scale would be 100 million years instead of a week). Similar experiments, both with different sources of energy and with different mixtures of gases, have resulted in amino and hydroxy acids being produced; it is likely that at least some organic compounds would have been generated on the early Earth.

However, when oxygen gas is added to this mixture, no organic molecules are formed. Opponents of Miller-Urey hypothesis seized upon recent research that shows the presence of uranium in sediments dated to 3.7 Ga and indicates it was transported in solution by oxygenated water (otherwise it would have precipitated out). These opponents argue that this presence of oxygen precludes the formation of prebiotic molecules via a Miller-Urey-like scenario, attempting to invalidate the hypothesis of abiogenesis. However, the authors of the paper are arguing that this presence of oxygen merely evidences the existence of photosynthetic organisms 3.7 Ga ago (a date about 200 Ma earlier than previous estimates) a conclusion which while pushing back the time frame in which Miller-Urey reactions and abiogenesis could potentially have occurred, would not preclude them. Though there is somewhat controversial evidence for very small (less than 0.1%) amounts of oxygen in the atmosphere almost as old as Earth's oldest rocks, the authors are not in any way arguing for the existence of an oxygen-rich atmosphere any earlier than previously thought, and they state: ". . . In fact most evidence suggests that oxygenic photosynthesis was present during time periods from which there is evidence for a non-oxygenic atmosphere".

Conditions similar to those of the Miller-Urey experiments are present in other regions of the solar system, often substituting ultraviolet light for lightning as the driving force for chemical reactions. The Murchison meteorite that fell near Murchison, Victoria, Australia in 1969 was found to contain over 90 different amino acids, nineteen of which are found in Earth life. Comets and other icy outer-solar-system bodies are thought to contain large amounts of complex carbon compounds (such as tholins) formed by these processes, in some cases so much so that the surfaces of these bodies are turned dark red or as black as asphalt. The early Earth was bombarded heavily by comets, possibly providing a large supply of complex organic molecules along with the water and other volatiles they contributed. This has been used to infer an origin of life outside of Earth: the Panspermia hypothesis.

Recent related studies

During recent years, studies have been made of the amino acid composition of the products of "old" areas in "old" genes, defined as those that are found to be common to organisms from several widely separated species, assumed to share only the last universal ancestor (LUA) of all extant species. These studies found that the products of these areas are enriched in those amino acids that are also most readily produced in the Miller-Urey experiment. This suggests that the original genetic code was based on a smaller number of amino acids -- only those available in prebiotic nature -- than the current one.

See also

References

External links

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