Share to: share facebook share twitter share wa share telegram print page

David Blackwell

For the American football coach, see David Blackwell (American football).
David Blackwell
Blackwell in 1999
Born
David Harold Blackwell

(1919-04-24)April 24, 1919
Centralia, Illinois, U.S.
DiedJuly 8, 2010(2010-07-08) (aged 91)[3]
Berkeley, California, U.S.
EducationUniversity of Illinois at Urbana-Champaign (BA, MA, PhD)
Known forRao–Blackwell theorem
Blackwell channel
Arbitrarily varying channel
Games of imperfect information
Dirichlet distribution
Blackwell's informativeness theorem
Bayesian statistics
Mathematical economics
Recursive economics
Sequential analysis
AwardsMember of the National Academy of Sciences (1965)
John von Neumann Theory Prize (1979)
R. A. Fisher Lectureship (1986)
Scientific career
FieldsProbability
Statistics
Logic
Game theory
Dynamic programming[1]
InstitutionsUniversity of California, Berkeley
ThesisSome properties of Markoff chains (1941)
Doctoral advisorJoseph Leo Doob[2]
Doctoral students

David Harold Blackwell (April 24, 1919 – July 8, 2010) was an American statistician and mathematician who made significant contributions to game theory, probability theory, information theory, and statistics.[1] He is one of the eponyms of the Rao–Blackwell theorem.[4] He was the first African American inducted into the National Academy of Sciences, the first African American full professor (with tenure) at the University of California, Berkeley,[3][5][6] and the seventh African American to receive a Ph.D. in mathematics.[7] In 2012, President Barack Obama posthumously awarded Blackwell the National Medal of Science.

Blackwell was also a pioneer in textbook writing. He wrote one of the first Bayesian statistics textbooks, his 1969 Basic Statistics. By the time he retired, he had published over 90 papers and books on dynamic programming, game theory, and mathematical statistics.[8]

Early life and education

David Harold Blackwell was born on April 24, 1919, in Centralia, Illinois, to Mabel Johnson Blackwell, a full-time homemaker, and Grover Blackwell, an Illinois Central Railroad worker.[9] He was the eldest of four children[8] with two brothers, J. W. and Joseph, and one sister, Elizabeth. Growing up in an integrated community, Blackwell attended "mixed" schools, where he distinguished himself in mathematics. During elementary school, his teachers promoted him beyond his grade level on two occasions. It was in a high school geometry course, however, that his passion for mathematics began.[10] An exceptional student, Blackwell graduated high school in 1935 at the age of sixteen.[9]

Blackwell entered the University of Illinois at Urbana-Champaign with the intent to study elementary school mathematics and become a teacher. He was a member of Alpha Phi Alpha, a black fraternity that housed him for his full six years as a student. He earned his bachelor's degree in mathematics in three years in 1938 and, a year later, a master's degree in 1939. He was awarded a Doctor of Philosophy in mathematics in 1941[2] at the age of 22.[9][11][12] His doctoral advisor was Joseph L. Doob. At the time, Blackwell was the seventh African American to earn a Ph.D. in mathematics in the United States and the first at the University of Illinois at Urbana-Champaign. His doctoral thesis was on Markov chains.

Career and research

Postdoctoral study and early career

Blackwell completed one year of postdoctoral research as a fellow at the Institute for Advanced Study (IAS) at Princeton in 1941 after receiving a Rosenwald Fellowship, which was a fund to aid black scholars.[12] There he met John von Neumann, who asked Blackwell to discuss his Ph.D. thesis with him.[13] Blackwell, who believed that von Neumann was just being polite and not genuinely interested in his work, did not approach him until von Neumann himself asked him again a few months later. According to Blackwell, "He (von Neumann) listened to me talk about this rather obscure subject and in ten minutes he knew more about it than I did."[14]

While a postdoc at IAS, Blackwell was prevented from attending lectures or undertaking research at nearby Princeton University, which the IAS has historically collaborated with in research and scholarship activities,[15] because of his race.[12]

From left to right: Abdulalim Shabazz, David Blackwell, and J. Ernest Wilkins Jr. at the Conference for African American Researchers in the Mathematical Sciences in June 1995.

Seeking a permanent position elsewhere, he wrote letters of application to 104 historically black colleges and universities in 1942, and received a total of only three offers. He felt at the time that a black professor would be limited to teaching at black colleges.[16] Having been highly recommended by his dissertation advisor Joseph L. Doob for a position at the University of California, Berkeley, he was interviewed by statistician Jerzy Neyman. Neyman supported his appointment, and Griffith C. Evans, the head of the mathematics department, at first agreed and even convinced university president Robert Sproul that it was the correct decision, only to subsequently balk, citing the concerns of his wife. It was customary for Evans and his wife to invite the members of the department over for dinner and "she was not going to have any darkie in her house."[17][18]

He was offered a post at Southern University at Baton Rouge, which he held in from 1942 to 1943, followed by a year as an Instructor at Clark College in Atlanta.

Howard University

Blackwell joined the Mathematics Department at Howard University in 1944. When he joined, he was one of four faculty members and within three years he was appointed full professor and head of the department.[12] He remained at Howard until 1954. In 1947, while at Howard, Blackwell published the paper "Conditional Expectation and Unbiased Sequential Estimation", which outlined a technique that later became known as the Rao-Blackwell theorem.[19] The theorem provides a method for improving statistical estimates by potentially reducing their mean squared error.

From 1948 to 1950, Blackwell spent his summers at RAND Corporation with Meyer Abraham Girshick and other mathematicians exploring the game theory of duels. In 1954, Girshick and Blackwell published Theory of Games and Statistical Decisions.[20] Aside from von Neumann and Girshick, other Blackwell collaborators and mentors included Leonard J. Savage, Richard E. Bellman, and Nobel Laureate Kenneth J. Arrow.[21]

University of California, Berkeley

Blackwell took a position at the University of California, Berkeley as a visiting professor in 1954, and was hired as a full professor in the newly created Department of Statistics in 1955. He became the Statistics department chair in 1957.[12][22][23]

Blackwell bridged topology and game theory via a game-theoretic proof of Kuratowski's theorem in 1967.[24] Blackwell only briefly extended his research beyond zero-sum games to explore the sure-thing principle[25][26] as introduced by Jimmie Savage,[27] primarily due the real-world societal implications of the mathematical result,[clarification needed][28] particularly for nuclear disarmament[how?] at the inception of the Cold War.[29]

Blackwell wrote one of the first Bayesian textbooks, his 1969 Basic Statistics. It inspired the 1995 textbook Statistics: A Bayesian Perspective by the biostatistician Donald Berry.

He spent the rest of his career at UC Berkeley, retiring in 1988[12][23] at age 70, which at that time was the mandatory retirement age. Over the course of his career, he mentored over 60 students.[2]

Personal life and death

Blackwell married Annlizabeth Madison, a 1934 graduate of Spelman College, on December 27, 1944.[8] They had eight children together,[30] three sons and five daughters: Ann, Julia, David, Ruth, Grover, Vera, Hugo, and Sara.

David Blackwell died of complications from a stroke on July 8, 2010, at Alta Bates Summit Medical Center in Berkeley, California.[31] He was 91 years old.

Honors and awards

In his lifetime, Blackwell received 12 honorary doctorates.

Legacy

The Mathematical Association of America's MathFest, in coordination with the National Association of Mathematicians, features an annual MAA-NAM David Blackwell Lecture.[7] Blackwell offered the inaugural address in 1994; and subsequent lecturers are researchers who "exemplif[y] the spirit of Blackwell in both personal achievement and service to the mathematical community."[37]

The Blackwell-Tapia prize is named in honor of David Blackwell and Richard A. Tapia.

The University of California, Berkeley named an undergraduate residence hall in his honor, named David Blackwell Hall. The residence hall opened in Fall 2018.[38]

An educational book about his life titled David Blackwell and the Deadliest Duel was published in 2019.

Blackwell made the following statement about his values and work in a 1983 interview for a project called "Mathematical People":

Basically, I'm not interested in doing research and I never have been....I'm interested in understanding, which is quite a different thing. And often to understand something you have to work it out yourself because no one else has done it.[12]

In March 2024, Nvidia announced its Blackwell GPU architecture, named in honour of David Blackwell.[39][40]

See also

Bibliography

Books

  • Blackwell, David; Girshick, M. A. (1954). Theory of Games and Statistical Decisions. New York: John Wiley & Sons. ISBN 0-486-63831-6.
  • Blackwell, D. (1969). Basic Statistics. McGraw Hill.

Journal articles

References

  1. ^ a b David Blackwell publications indexed by Google Scholar Edit this at Wikidata
  2. ^ a b c David Blackwell at the Mathematics Genealogy Project Edit this at Wikidata
  3. ^ a b Sorkin, Michael (July 14, 2010). "David Blackwell fought racism; become world-famous statistician". St. Louis Post-Dispatch. Retrieved April 10, 2024.
  4. ^ Roussas, G.G. et al. (2011) A Tribute to David Blackwell, NAMS 58(7), 912–928.
  5. ^ Cattau, Daniel (July 2009). "David Blackwell 'Superstar'". Illinois Alumni. University of Illinois Alumni Association. pp. 32–34.
  6. ^ "Joseph Thomas Gier; "Wasn't David Blackwell First?"". Joseph Gier Memorial Project. Berkeley EECS. Retrieved September 26, 2023.
  7. ^ a b Schoemig, Skylar (February 25, 2020). "'A Berkeley hero': UC Berkeley professors, alumnus reflect on legacy of David Blackwell". The Daily Californian. Retrieved June 18, 2021.
  8. ^ a b c Marlow Anderson (March 31, 2009). Who Gave You the Epsilon?: And Other Tales of Mathematical History. MAA. pp. 98–. ISBN 978-0-88385-569-0.
  9. ^ a b c C., Bruno, Leonard (2003) [1999]. Math and mathematicians : the history of math discoveries around the world. Baker, Lawrence W. Detroit, Mich.: U X L. ISBN 0787638137. OCLC 41497065.{{cite book}}: CS1 maint: multiple names: authors list (link)
  10. ^ "Blackwell, David Harold (1919-2010) | The Black Past: Remembered and Reclaimed". Black Past. July 27, 2010. Retrieved September 26, 2017.
  11. ^ Kessler, James H.; Kidd, J. S.; Kidd, Renée A.; Morin, Katherine A. (1996). Distinguished African American Scientists of the 20th Century. Phoenix, AZ: Oryx Press. ISBN 0-89774-955-3.
  12. ^ a b c d e f g Grime, David (July 17, 2010). "David Blackwell, Scholar of Probability, Dies at 91". The New York Times. Retrieved April 10, 2024.
  13. ^ Gary Musser, Lynn Trimpe; Gary Musser; Lynn Trimpe (2007). Harold R. Parks (ed.). A Mathematical View of Our World. Cengage Learning. p. 32. ISBN 9780495010616.
  14. ^ Steven Krantz (2005). Mathematical Apocrypha Redux: More Stories and Anecdotes of Mathematicians and the Mathematical. Cambridge University Press. p. 225. ISBN 9780883855546.
  15. ^ "Mission and History". Institute for Advances Studies. March 15, 2016.
  16. ^ Albers, Donald J. (2008). "David Blackwell". In Albers, Donald J.; Alexanderson, Gerald L. (eds.). Mathematical People: Profiles and Interviews (2nd ed.). A K Peters. ISBN 978-1-56881-340-0.
  17. ^ "David Blackwell: Berkley [sic]". YouTube. March 12, 2010. Retrieved June 10, 2020.
  18. ^ Black, Robert (2019). David Blackwell and the Deadliest Duel. Unionville, NY: Royal Fireworks Press. pp. 57–59.
  19. ^ Blackwell, David (1947). "Conditional expectation and unbiased sequential estimation". Annals of Mathematical Statistics. 18 (1): 105–110. doi:10.1214/aoms/1177730497. MR 0019903. Zbl 0033.07603.
  20. ^ Blackwell, David; Girshick, M. A. (1954). Theory of Games and Statistical Decisions. New York: John Wiley & Sons. ISBN 0-486-63831-6.
  21. ^ Arrow, K. J., D. Blackwell and M. A. Girshick “Bayes and Minimax Solutions of Sequential Decision Problems” Econometrica Vol. 17, No. 3/4 (Jul. - Oct., 1949), pp. 213-244.
  22. ^ DeGroot, Morris H. (1986). "A conversation with David Blackwell". Statistical Science. 1 (1): 40–53. doi:10.1214/ss/1177013814.
  23. ^ a b "David Blackwell". Mathematics at Illinois. Retrieved November 3, 2021.
  24. ^ Blackwell, David (1967). "Infinite Games and Analytic Sets". Proceedings of the National Academy of Sciences. 58 (5): 1836–1837. Bibcode:1967PNAS...58.1836B. doi:10.1073/pnas.58.5.1836. PMC 223869. PMID 16578685.
  25. ^ Jeffrey, Richard (1982). "The Sure Thing Principle". Proceedings of the Biennial Meeting of the Philosophy of Science Association. 1982 (2): 719–730. 10.1086/psaprocbienmeetp.1982.2.192456.JSTOR 192456.S2CID 124506828.
  26. ^ Pearl, Judea (December 2015). "The sure-thing principle" (PDF). UCLA Cognitive Systems Laboratory, Technical Report R-466.
  27. ^ Savage, L. J. (1954), The foundations of statistics. John Wiley & Sons Inc., New York.
  28. ^ 7. Blyth, C. (1972). "On Simpson's paradox and the sure-thing principle". Journal of the American Statistical Association. 67 (338): 364–366. 10.2307/2284382. JSTOR 2284382.
  29. ^ Agwu, Nkechi; Smith, Luella; Barry, Aissatou (February 2003). "Dr. David Harold Blackwell, African American Pioneer" (PDF). Mathematics Magazine. 76 (1): 3–14. doi:10.1080/0025570X.2003.11953941. S2CID 120904626.
  30. ^ Spelman Messenger Spelman College
  31. ^ Brown, Emma (July 16, 2010). "David H. Blackwell dies at 91; pioneering statistician at Howard and Berkeley". The Washington Post. ISSN 0190-8286. Retrieved September 26, 2017.
  32. ^ "David Blackwell". Recognizing Excellence/Award Recipients. INFORMS. Retrieved June 12, 2019.
  33. ^ "R.A. Fisher Award and Lectureship - Past Recipients". Committee of Presidents of Statistical Societies. Retrieved June 12, 2019.
  34. ^ "APS Member History". search.amphilsoc.org. Retrieved April 19, 2022.
  35. ^ Fellows: Alphabetical List, Institute for Operations Research and the Management Sciences, retrieved October 9, 2019
  36. ^ "Laureates - David Blackwell". National Science & Technology Medals Foundation. Retrieved May 21, 2018.
  37. ^ "MAA-NAM Blackwell Lecture". www.nam-math.org. Archived from the original on June 23, 2021. Retrieved June 18, 2021.
  38. ^ Kane, Will (February 8, 2018). "New dorm to honor Berkeley's first tenured black professor". UC Berkeley. Retrieved May 21, 2018.
  39. ^ "Nvidia Blackwell Platform Arrives to Power a New Era of Computing". Nvidia Newsroom. Retrieved March 18, 2024.
  40. ^ Leswing, Kif (March 18, 2024). "Nvidia CEO Jensen Huang announces new AI chips: 'We need bigger GPUs'". CNBC. Retrieved March 18, 2024.
Wikimedia Commons has media related to David Blackwell.

Read other articles:

Cyane Fossae

Fossae on Mars Cyane FossaeCyane Fossae based on THEMIS day-time imageCoordinates31°18′N 121°12′W / 31.3°N 121.2°W / 31.3; -121.2 Cyane Fossae is a trough in the Diacria quadrangle of Mars. It is centered at 31.3° north latitude and 121.2° west longitude. It is 913 kilometres (567 mi) long and was named after a classical albedo feature name.[1] The term fossae is used to indicate large troughs when using geographical terminology related to Mars. ...

 

David O'Connor (cavaliere)

David O'Connor Nazionalità  Stati Uniti Equitazione Specialità Concorso completo Palmarès Competizione Ori Argenti Bronzi Giochi olimpici 1 1 1 Mondiali 1 0 1 Giochi panamericani 1 1 0 Per maggiori dettagli vedi qui   Modifica dati su Wikidata · Manuale David John O'Connor (Washington, 18 gennaio 1962) è un cavaliere statunitense. Ha rappresentato gli Stati Uniti d'America nel concorso completo ed ha partecipato a due Olimpiadi, vincendo una medaglia d'argento nel concorso...

 

The Way I Feel (album de Sonny Rollins)

The Way I Feel Album de Sonny Rollins Sortie 1976 Enregistré Aout et octobre 1976 Durée 36:55 Genre Jazz (jazz fusion) Producteur Orrin Keepnews Label Milestone Records Critique AllMusic [1] Albums de Sonny Rollins Nucleus(1975) Easy Living(1977)modifier The Way I Feel est un album du saxophoniste ténor Sonny Rollins paru en 1976 sur le label Milestone. Réception L'auteur et critique de jazz Scott Yanow considère cet enregistrement comme l'un des moins bon de Rollins dans les ann

Dord (instrument)

Bronze Age horns in the Irish Museum. The largest in this image is 7+1⁄2 feet (2.3 m) long, with the second largest at 6 feet (1.8 m). The dord is a bronze horn native to Ireland,[1] with excavated examples dating back as far as 1000 BC, during the Bronze Age. A number of original dords are known to exist,[citation needed] with some replicas also being built in the late 20th century.[2][3] Though the musical tradition of the dord has been lost, ...

 

TEN

TEN kan verwijzen naar: Trans-Europese Netwerken Toxische epidermale necrolyse, een ernstige huidaandoening Ten, het debuutalbum van de rockband Pearl Jam Bekijk alle artikelen waarvan de titel begint met TEN of met TEN in de titel. Dit is een doorverwijspagina, bedoeld om de verschillen in betekenis of gebruik van TEN inzichtelijk te maken. Op deze pagina staat een uitleg van de verschillende betekenissen van TEN en verwijzingen daarnaartoe. Bent u hier via een pagin...

 

ديفيد دورفمان

ديفيد دورفمان معلومات شخصية الميلاد 7 فبراير 1993 (العمر 30 سنة)لوس أنجلوس مواطنة الولايات المتحدة  الحياة العملية المدرسة الأم كلية هارفارد للحقوقجامعة كاليفورنيا  المهنة ممثل اللغة الأم الإنجليزية  اللغات الإنجليزية  سنوات النشاط 1998-الآن المواقع IMDB صفحته على IMDB&#...

الأفكار السياسية في أدب الخيال العلمي

هذه المقالة يتيمة إذ تصل إليها مقالات أخرى قليلة جدًا. فضلًا، ساعد بإضافة وصلة إليها في مقالات متعلقة بها. (سبتمبر 2021) يمكن القول إن استكشاف السياسة في الخيال العلمي أقدم من تحديد هذا النوع الأدبي. يعد آلة الزمن للمؤلف ه. ج. ويلز أحد أقدم أعمال الخيال العلمي الحديث، وهي استقر�...

 

Wonderland Live

2017 concert tour by Take That Parts of this article (those related to documentation) need to be updated. Please help update this article to reflect recent events or newly available information. (May 2017) Wonderland LiveTour by Take ThatAssociated albumWonderlandStart date5 May 2017 (2017-05-05)End date29 November 2017 (2017-11-29)Legs3No. of shows30 in UK & Ireland7 in Oceania2 in Asia39 TotalSupporting act(s)All Saints (UK & Ireland)Dannii Minogue (Aus...

 

Trần Đình Long (nhà cách mạng)

Đối với các định nghĩa khác, xem Trần Đình Long. Trần Đình Long (1 tháng 3 năm 1904 - 1945) là nhà hoạt động cách mạng trong phong trào cộng sản Việt Nam, là cố vấn của Ủy ban khởi nghĩa Hà Nội trong Cách mạng tháng 8 năm 1945. Ông còn là một nhà văn, nhà báo và nhà hoạt động sân khấu, với bút danh Lương Phong hoặc tên viết tắt T.Đ.L, L.P. Hoạt động cách mạng Thời kỳ đầu Ông sinh ngày 1 th

Kabupaten Natuna

Kabupaten NatunaKabupatenTranskripsi bahasa daerah • Abjad JawiناتوناGunung Ranai Natuna LambangMotto: Laut sakti rantau bertuahPetaKabupaten NatunaPetaTampilkan peta SumatraKabupaten NatunaKabupaten Natuna (Indonesia)Tampilkan peta IndonesiaKoordinat: 4°00′N 108°15′E / 4°N 108.25°E / 4; 108.25Negara IndonesiaProvinsiKepulauan RiauDasar hukumUndang-Undang No. 53 Tahun 1999Ibu kotaRanaiJumlah satuan pemerintahan Daftar Kecamatan:...

 

警部補

警部補（けいぶほ、英称：Inspector）は、警察法第62条に規定される日本の警察官の階級の一。警部の下、巡査部長の上に位置する。 警部補の階級章 概要 多くの警察本部では主任〜係長、警察署では係長級、交番では俗に「ハコ長」と呼ばれる交番の責任者（交番所長）となる。英語のInspector及びLieutenantの訳語にも充てられる。公式な英訳については「警察官及び皇宮護

 

Keuskupan Požega

Keuskupan PožegaDioecesis PoseganaPožeška biskupijaKatolik Lambang uskup Antun ŠkvorčevićLokasiNegara KroasiaProvinsi gerejawiĐakovo-OsijekStatistikLuas6.931 km2 (2.676 sq mi)Populasi- Total- Katolik(per 2013)286.285254,937 (89.1%)InformasiDenominasiKatolik RomaRitusRitus RomaPendirian5 Juli 1997KatedralKatedral St. Teresa dari ÁvilaPelindungSanto LawrensiusKepemimpinan kiniPausFransiskusUskupAntun Škvorčević Bishop of PožegaUskup agungĐuro...

Commedia all'italiana

Italian film genre For the Italian improvisational theatre, see Commedia dell'arte. Big Deal on Madonna Street by Mario Monicelli (1958) Commedia all'italiana (pronounced [komˈmɛːdja allitaˈljaːna]; pl.: commedie all'italiana, comedy in the Italian way), or Italian-style comedy, is an Italian film genre born in Italy in the 1950s and developed in the 1960s and 1970s. It is widely considered to have started with Mario Monicelli's Big Deal on Madonna Street in 1958,[1] and ...

 

Haberdashers' Boys' School

Public school in Hertfordshire, England Haberdashers' Boys' School Coat of arms Boys playing cricket in front of Aldenham HouseAddressButterfly LaneElstree, Hertfordshire, WD6 3AFUnited KingdomCoordinates51°39′23″N 0°18′45″W / 51.6564°N 0.3124°W / 51.6564; -0.3124InformationType4–18 boys Private school and Independent day schoolMottoMaking a Profound ImpactReligious affiliation(s)Church of EnglandEstablished1690; 333 years ago (1690)Depa...

 

Russian Ark

2002 filmRussian ArkTheatrical release posterDirected byAlexander SokurovWritten byAnatoli NikiforovAlexander SokurovProduced byAndrey DeryabinJens MeurerKarsten StöterStarring Alexander Sokurov Sergey Dreyden Mariya Kuznetsova Marksim Sergeyev Anna Aleksakhina Vladimir Baranov Narrated byAlexander SokurovCinematographyTilman BüttnerEdited byStefan CiupekSergei IvanovBetina KuntzschPatrick WilfertMusic bySergei YevtushenkoProductioncompanySeville PicturesDistributed byWellspring MediaReleas...

وزارة العمل (الولايات المتحدة)

  لمعانٍ أخرى، طالع وزارة العمل (توضيح).    وزارة العمل (الولايات المتحدة) وزارة العمل (الولايات المتحدة) وزارة العمل (الولايات المتحدة)ختم   تفاصيل الوكالة الحكومية البلد الولايات المتحدة  مؤسس ويليام هوارد تافت  تأسست 4 مارس 1913؛ منذ 110 سنين (1913-03-04)...

 

Malia sulawesi

Malia sulawesi Malia grata di Cagar Alam Gunung Ambang, Sulawesi Utara Status konservasi Risiko Rendah (IUCN 3.1)[1] Klasifikasi ilmiah Kerajaan: Animalia Filum: Chordata Kelas: Aves Ordo: Passeriformes Famili: Timaliidae[1] Genus: MaliaSchlegel, 1880 Spesies: M. grata Nama binomial Malia grataSchlegel, 1881 Malia sulawesi (Malia grata) adalah spesies burung malia dalam famili Timaliidae. Burung ini endemik di Pulau Sulawesi,[2] menghuni hutan-hutan pegununga...

 

مسجد الراية (المدينة المنورة)

24°28′48.89″N 39°36′11.60″E / 24.4802472°N 39.6032222°E / 24.4802472; 39.6032222 مسجد الراية إحداثيات 24°28′48.89″N 39°36′11.60″E / 24.4802472°N 39.6032222°E / 24.4802472; 39.6032222 معلومات عامة القرية أو المدينة المدينة المنورة الدولة  السعودية تاريخ بدء البناء هـ / 640 النمط المعماري مسجد معلومات أخر�...

Dorothy H. Turkel House

Building in Detroit, MichiganDorothy H. Turkel HouseGeneral informationArchitectural styleUsonianLocation2760 West 7 Mile RoadDetroit, MichiganCoordinates42°25′57″N 83°07′51″W / 42.432363°N 83.130865°W / 42.432363; -83.130865Completed1956Design and constructionArchitect(s)Frank Lloyd Wright The Dorothy H. Turkel House is a private residence located at 2760 West 7 Mile Road in north-central Detroit, Michigan, within the Palmer Woods neighborhood. It was desi...

 

Trophic level

Position of an organism in a food chain Not to be confused with Trophic level index. First trophic level. The plants in this image, and the algae and phytoplankton in the lake, are primary producers. They take nutrients from the soil or the water, and manufacture their own food by photosynthesis, using energy from the sun. The trophic level of an organism is the position it occupies in a food web. A food chain is a succession of organisms that eat other organisms and may, in turn, be eaten th...

 
Kembali kehalaman sebelumnya