AcharyaChanakya/simple-wikipedia huggingface dataset:
Lake Macquarie is connected to the sea by Swansea Channel and Lakes Entrance. Swansea Channel is about wide and long. The bridges over the channel can lift to allow yachts and other boats in and out of the lake.
The eucalypt forests on the southern edge of the lake have been listed by BirdLife International as a 121 km Important Bird Area (IBA). They support significant numbers of endangered Swift Parrots and Regent Honeyeaters. Masked Owls and Ospreys often nest in the area.
In 1983 the State Pollution Control Commission studied the poor water quality of Lake Macquarie. It found increased amounts of sediment and increased levels of nutrients were causing problems. Further studies in 1995 found that creeks flowing into the lake were causing many of these problems. In 1998 a special group was set up by the government to find ways to protect the lake. This group recommended setting up the Lake Macquarie Project Management Committee. Their job was to put in place an action plan to protect the lake called the Lake Macquarie Improvement Plan.
These actions have included reducing the amount of sediment and nutrients getting into the lake. They have built wetlands, stormwater treatments, replanting, and educating the local community.
There are more fish in the lake because commercial fishing has been stopped in the lake and the water quality is improving.
Fishing, boating, kayaking and water skiing are all popular activities on the lake.
La Torbiera Zoo
Blue Lake (South Australia)
The Blue Lake is in Mount Gambier, South Australia. It is in an extinct volcanic crater, which is part of the Mount Gambier complex. It is one of four crater lakes on Mount Gambier. Leg of Mutton Lake and Brown Lake have dried up over the past 30 to 40 years as the water table has dropped. The Blue Lake is known for its changing color, from grey to bright blue.
Different dates have been given for its last eruption, of 28,000 years ago, 4300 years ago, and, recently, a little before 6000 years ago. If the youngest date is correct, this could be the most recent volcanic eruption on the Australian mainland.
Blue Lake is thought to be of an average depth of 72 metres, but in places reaches 77 metres deep. The crater rim measures 1,200 metres (3,937 feet) by 824 metres (2,703 feet). The lake itself measures 1,087 metres (3,566 feet) by 657 metres (2,155 feet). The bottom of the lake is 30 metres (100 feet) below the level of the main street of the nearby town. The Blue Lake supplies the town with drinking water.
In 1967 a survey found the deepest point in the lake at 77 m. Major diving exploration of the lake first took place in 1985. Cave diver Peter Horne studied the temperature and visibility of the water. He discovered a fresh water sponge species and other invertebrates. He also discovered "The Stromatolite Field", hollow rock formations on the north-eastern edge at a depth of 40 m. In 2008 another dive brought up core samples from the calcite-silt covered lake bed, and measured the water temperature on the lake bed at 14 degrees Celsius (57 °F).
During December to March, the lake turns to a vibrant cobalt blue colour. It changes to a colder steel grey colour for April to November. Why this happens is still a mystery. Scientists believe water on the surface becomes warmer in summer. This causes calcium carbonate to precipitate out of solution and allows micro-crystallites of calcium carbonate to form. This results in scatter of the blue wavelengths of sunlight. During winter the lake water becomes well mixed, and the lake water is less clear because of tannins and calcium carbonate particles. The angle of the sun has also been found to influence the perceived colour of the lake. The movement of planktonic life-forms within the lake during the seasons and during the day may also play a part in the colour change.
In July 1865 Adam Lindsay Gordon performed the daring horse riding feat known as Gordon’s Leap on the edge of the Blue Lake. A commemorative obelisk was built at the spot. The sign on it reads: "This obelisk was erected as a memorial to the famous Australian poet. From near this spot in July, 1865 Gordon made his famed leap on horseback over an old post and rail guard fence onto a narrow ledge overlooking the Blue Lake and jumped back again onto the roadway. The foundation stone of the Gordon Memorial Obelisk was laid on 8th July 1887".
Borophagus
Borophagus is an extinct genus of the Canidae family, endemic to North America. The species were similar in appearance to modern-day hyenas, and weighed between and . There are eight known species that lived from around 12 million years ago to about 2 million years ago.
Probability space
Probability space is a mathematical model used to describe scientific experiments. A probability space consists of three parts:
An "outcome" is the result of a single execution of the model. Since individual outcomes might be of little practical use, more complex "events" are used to characterize groups of outcomes. The collection of all such events is a "σ-algebra", sometimes written as formula_3. Finally, there is a need to specify each event's likelihood of happening. This is done using the "probability measure" function, "P".
Once the probability space is established, one usually assumes that “nature” makes its move and selects a single outcome, "ω", from the sample space Ω. All the events in formula_3 that contain the selected outcome "ω" (recall that each event is a subset of Ω) are said to “have occurred”. The selection performed by nature is done in such a way that if the experiment were to be repeated an infinite number of times, then the relative frequencies of occurrence of each of the events would coincide with the probabilities described by the function "P".
The prominent Soviet mathematician Andrey Kolmogorov introduced the notion of probability space, together with other axioms of probability, in the 1930s.
The Gambler (novel)
The Gambler is a novel by the Russian author Fyodor Dostoyevsky.
It is about the bad side of gambling and has to do with Dostoyevsky's own experiences from his travels to Wiesbaden, Baden-Baden and other casinos. At the time when he wrote The Gambler he had serious financial problems. The Gambler was also turned into an opera by Sergei Prokofiev.
The Gambler was made public in 1867 short time after Crime and Punishment. In the summer 1865 Dostoyevsky had promised to his publisher Stellovsky to create a novel until 1. November. Otherwise the publisher would get the publishing rights for other works of Dostoyevsky without having to pay. Dostoyevsky accepted this. So Dostoyevsky dictated the novel in only 26 days to his typist and later wife Anna. Stellovsky left St. Petersburg on 31. October to make the delivery impossible. But Anna had the idea to deliver the novel to a notary (a kind of a lawyer) and like that they were able to deliver the novel until the promised date.
POST (HTTP)
Festspielhaus Baden-Baden
The Amazing Spiez!
The Amazing Spiez! is a French/Canadian animated television series. It is produced by the French company Marathon Media and the Canadian company Image Entertainment Corporation. It was first broadcast on March 15, 2009 on Disney Channel Asia. It aired on TF1 in France and Teletoon in Canada. The series had 52 episodes (2 seasons). It aired its last episode on May 25, 2012. Its spinoff is "Totally Spies".
4 kids are secretly undercover as spiez! for WOOHP taking down Baddies headed by Jerry Lewis the Head/Founder of WOOHP a secret spy organization.
List of The Amazing Spiez! episodes
"The Amazing Spiez!" had 52 episodes. Each episode was 26 minutes long. The series had 52 episodes divided in 2 seasons. The series first episode premiered on March 15 2009 and the last episode premiered on May 25, 2012.
The series came on Disney Channel Asia, TF1, Teletoon, Cartoon Network USA, NHK Japan, Canal J and other networks
Arvind Kejriwal (born 16 August 1968) is an Indian politician. He is the current and 7th Chief Minister of Delhi. He is the national convener of Aam Aadmi Party (AAP). He started the Aam Aadmi Party in 2012. Kejriwal won the TIME 100 Readers' Poll in 2014.For the 2019 general elections the Aam Aadmi Party shared seats with the Indian National Congress.
Kejriwal was born in Bhiwani, Haryana on 16th August 1968. He was educated at Campus School in Hisar. He graduated from Indian Institute of Technology Kharagpur, majoring in mechanical engineering.
In November 2012, Kejriwal launched AAP.
AAP contested Delhi legislative assembly elections in 2013. Kejriwal defeated incumbent Chief Minister, Sheila Dikshit of the Indian National Congress (INC). Kejriwal was sworn in as the second-youngest chief minister of Delhi on 28 December 2013.
On 14 February 2014 he resigned as Chief Minister.
Kejriwal contested in 2014 Indian general elections. He lost against the BJP prime ministerial candidate, Narendra Modi.
Aam Aadmi Party won 67 of the 70 constituencies in the 2015 Delhi Assembly elections. Arvind Kejriwal took oath on 14 February 2015 as Delhi's chief minister for a second time.
Brody Dalle
Brody Dalle (born Bree Joanna Alice Robinson on January 1, 1979) is an Australian singer and guitarist from Melbourne. She started The Distillers in 1998. Her first solo album was released on April 28, 2014.
Dalle was married to Tim Armstrong from 1997 until they divorced in 2003. She married Josh Homme in 2007. She lives with him in California.
Manuel Ortega (painter)
Madrid Manuel Ortega (1921 – 14 April 2014) was a Spanish painter, muralist, sculptor, designer, portrait painter, and engraver. He was born in Madrid.
Ortega created more than 200 murals and created stained glass in many cathedrals, seminaries,palaces, hotels and developments from Spain. He won the international competition for the windows of the Cathedral of Almudena in Madrid in 1998.
Ortega died in Madrid from natural causes, aged 92.
Albert Manent
Albert Manent i Segimon (23 September 1930 – 14 April 2014) was a Spanish writer and cultural activist. He was mostly involved in the field of Catalan. Manent was the son of the writer Marià Manent. He graduated the subject of law and in Catalan philology. He was born in Premia de Dalt, Spain.
Manent died in Madrid from an illness, aged 83.
The New World Order (professional wrestling)
The New World Order (also known as just nWo) is a professional wrestling stable that is best known for competing in World Championship Wrestling (WCW) and World Wrestling Federation/Entertainment (WWF/E). The stable was created on July 7, 1996 and broke up on July 15, 2002. nWo had a gimmick of a group of unsanctioned wrestlers trying to "take over" WCW.
The nWo angle was based on Universal Wrestling Federation's invasion of New Japan Pro Wrestling. A well known moment happened at "Bash at the Beach" when Hulk Hogan unexpectedly turned heel for the first time in nearly fifteen years. The nWo angle is one of the most popular and successful angles in modern-day professional wrestling.
Alistair MacLeod
Alistair MacLeod, (July 20, 1936 – April 20, 2014) was a Canadian novelist, short story writer and academic. He was known for his novels in "No Great Mischief", "The Lost Salt Gift of Blood", and "As Birds Bring Forth the Sun and Other Stories". He was born in North Battleford, Saskatchewan, Canada.
MacLeod was born in North Battleford, Saskatchewan and died in Windsor, Ontario from a stroke, aged 77.
Sandy Jardine
William "Sandy" Pullar Jardine (31 December 1948 – 24 April 2014) was a Scottish professional footballer. Jardine played for Rangers, Hearts and represented Scotland.
Jardine died from liver cancer, aged 65.
Andréa Parisy
Andrée Marcelle Henriette Parisy (4 December 1935 – 27 April 2014), better known by her stage names Andréa Parisy and sometimes Andrée Parizy, was a French actress. She is best known for her roles in movies such as "Babes a GoGo" (1956), "The Little Bather" (1968) and "Mayerling" (1968). She was born in Levallois-Perret.
Parisy died on 27 April 2014, aged 78.
Steve Zabriskie
Steve Zabriskie is a former sportscaster. He was best known for calling Major League Baseball, football, and college basketball.
Zabriskie was the play-by-play voice for the New York Mets from 1983 through 1989. He also called games for the California Angels and did part time games for the Boston Red Sox as well as calling baseball games for USA, ABC Sports, and ESPN as well as calling college football for ABC, college basketball on ESPN and CBS, and NFL games for CBS.
Zabriskie used to live in Orlando, Florida. He currently lives in California. His wife of more than thirty years died of cancer.
Lake McKenzie
Lake McKenzie (Boorangoora) is a perched lake on Fraser Island in Queensland, Australia. The lake is located in the Great Sandy National Park. Fraser Island is the world's largest sand island and is also a World Heritage site. Half of the world's perched lakes are found on the island.
The lake is 6.2 km southeast of Kingfisher Resort. It is 1,200 metres long and up to 930 metres wide. It covers an area of about 150 hectares.
The sand around the lake is pure, white silica. The water in the lake is also so pure it is unsuitable for many species.
Facilities for visitors around the lake include camping areas, picnic areas, toilets and barbecues.
In March 1944 a military training camp was set up at the lake. It was closed late the same year.
The lake served as the final Roadblock location and the finish line of the TV series "The Amazing Race Australia 2".
Sarah Paulson
Sarah Catharine Paulson (born December 17, 1974) is an American actress. She was born in Tampa, Florida.
Paulson played Maggie Corner in the "Family Values" episode of Law & Order. She played Anne Gillette in the episode "Shadow" of the same series. She played several characters in different seasons of "American Horror Story". She played Dr. Caron in the movie "Serenity". She also starred in "The Post".
Antonio Pica
Antonio de la Santísima Trinidad Pica Serrano (March 21, 1933 — April 26, 2014) was a Spanish actor.
Pica was born in Jerez de la Frontera, Cádiz, Spain.
He appeared in over 60 movies since his career began in 1966. He worked with Sophia Loren and Christopher Plummer. He is known for his roles in "Delusions of Grandeur" (1971), "Travels with My Aunt" (1972) and "The Killer with a Thousand Eyes" (1974).
Pica died at a hospital in El Puerto de Santa María, Spain from an illness, aged 81.
Kent, Connecticut
Kent is a town in Litchfield County, Connecticut.
Ryan Tandy
Ryan Tandy (20 September 1981 – 28 April 2014) was an Australian professional rugby league player who played as both a prop and second row from 2003 until 2011. During his career, he played for the St. George Illawarra Dragons, South Sydney Rabbitohs, Wests Tigers, Melbourne Storm and the Canterbury-Bankstown Bulldogs in the National Rugby League (NRL). He also played for Hull Kingston Rovers in the European Super League. He represented Ireland from 2006 until 2008.
He was banned from playing professional rugby league due to a match fixing scandal. He was born in Wollongong, New South Wales.
Tandy was found dead of an apparent drug overdose on 28 April 2014 at his parents' home in Saratoga, New South Wales. He was 32.
Ground sloths are a group of extinct large sloths in the mammalian superorder Xenarthra. The much smaller living sloths are called "tree sloths".
The last surviving ground sloths lived in the Caribbean Antilles. "Megalocnus" may have survived until about the third century BC in Cuba. By then ground sloths had been extinct on the mainland of North and South America for 10,000 years or more. They survived on Caribbean islands because humans got to the islands much later. Some island sloth populations lived 5,000-6,000 years later than their continental mainland relatives. This fits the pattern of Holocene extinction of large vertebrates due to human dispersal. In other words, they were probably hunted or otherwise so affected by humans that they were unable to survive.
Most ground sloth evolution took place during the mid to late Tertiary of South America while the continent was isolated. At their earliest appearance in the fossil record, the ground sloths were already quite distinct. The presence of islands between the American continents in the Miocene allowed some to get into North America.
Ground sloths were a hardy group: their numbers and dispersals into remote areas are evidence of this. Remains have been found in parts of Alaska.
Sloths, and xenarthrans as a whole, were one of the more successful South American groups during the Great American Biotic Interchange. In general, during the interchange, many more taxa moved from North America into South America than in the other direction. However,at least five genera of ground sloths have been identified in North American fossils. These are examples of successful migration to the north.
Paramylodon
Paramylodon is an extinct genus of ground sloth. It was endemic to North America in the Pliocene, and to the end of the Pleistocene epoch. It lived from around ~4.9 million years ago (mya) to 11,000 years ago.
"Paramylodon" was about 3 m (9.8 ft) in height and weighted as much as 1089 kg. It is known from deposits in the United States, Mexico and as far south as Guatemala.
There is just one recognized species, "P. harlani", (Owen) 1840, which is commonly referred to as Harlan's ground sloth in honor of the American paleontologist who first discovered and described a lower jaw in 1835.
Like the South American "Mylodon", "Paramylodon" had dermal ossicles: small bones embedded in the skin. This made it harder for predators if they attacked from behind. Its skull and teeth suggest it was, like the other members of its group, a browser on leaves and small branches. It ate standing on its hind legs and using its huge hands to pull the vegetation into its mouth. Skeletons found in the La Brea tar pits were more or less complete.
Wilfred Thesiger
Wilfred Thesiger (June 3, 1910 – August 24, 2003) was born in Addis Ababa where his father was an advisor to the Ethiopian emperor. He went to school and university in England but he always dreamed of travel. He didn't make many friends when he studied in England. During his first university holidays he travelled alone, without much money, from England to Istanbul. This was the start of an exciting life filled with adventure in Africa, Iraq and the Arabian Peninsula.
Thesiger was one of the last great British explorers and he was an excellent photographer and writer. When Thesiger died in 2003, he left more than 38,000 photographs to the Pitt Rivers museum in Oxford. Thesiger wrote many books, some of which are considered to be classics. He was a tall, strong man and a successful boxer.
Thesiger travelled through the UAE with his Bedouin friends and even met Sheikh Zayed in Al Ain. (In 2003, the UAE gave money to the Pitt Rivers museum to help keep Thesiger's photos safe). Thesiger had a deep respect for his Bedouin friends who he thought of as better than himself because they were generous, brave and always cheerful. Each time Thesiger and his Bedouin friends met other people, they stopped, invited them to eat their food, and enjoyed sharing the latest news.
Thesiger loved a simple lifestyle. He didn't like cars or the radio. For the rest of his life he always wanted to go back to the desert.
He died in Croydon, London.
Penny Arcade is a webcomic about video games. It was created by Jerry Holkins and Mike Krahulik. The comic debuted in 1998. Now, the comic has its own website which also hosts other comic strips. In addition, the site has information about Child's Play, a children's charity, and PAX, a gaming convention. Both are by Holkins and Krahulik.
The comic strip is about two characters who are based on the creators of the comic strip. John "Gabe" Gabriel is based Mike Krahulik, and Tycho Brahe is based on Jerry Holkins. Gabrial is happier, but can become very angry. Tycho Brahe (named after the astronomer Tycho Brahe) is unhappy and serious. The characters go through the same events their creators do, but react differently. Most of the comic strips involve the two characters commenting on nerd culture, usually video games. The strip has large amounts of cursing and has been known to offend people.
Krahulik and Holkins have released podcasts called "Downloadable Content" since March 20, 2006. A series of four video games loosely based on the comic strip titled "" began on May 21, 2008. Tycho appeared in the game "Poker Night at the Inventory" alongside characters from "Team Fortress 2", "Strong Bad" and "Sam & Max". "Penny Arade: The Series" is a reality televesion show about the strip and the Penny Arcade company that began on February 20, 2010.
Operation Yewtree
Operation Yewtree is an investigation by the Metropolitan Police into sex crimes, especially child sexual abuse. It began in October 2012, after Jimmy Savile, who died in 2011, was found to have been a sexual predator for decades. People investigated include: Max Clifford, Dave Lee Travis, Rolf Harris, Gary Glitter, Freddie Starr, Paul Gambaccini, Chris Denning, Jim Davidson, Jimmy Tarbuck, Wilfred De'ath and Ted Beston.
Clifford, Harris and Denning have been convicted after being investigated by Operation Yewtree.
Yigal Arnon
Yigal Arnon (9 December 1929 – 27 April 2014) was an Israeli lawyer. He was best known as the founder of Yigal Arnon & Co., one of the largest law firms in Israel. He was born in Tel Aviv.
Arnon died on 27 April 2014 in Tel Aviv, aged 84.
Max Clifford
Maxwell Frank "Max" Clifford (6 April 1943 – 10 December 2017) was a British publicist and sex offender.
Clifford was born in Kingston upon Thames and raised in Wimbledon. He left school when he was 15.
Clifford was married to Elizabeth Porter from 1967 until her death in 2003. He has a daughter by her. He married Jo Westwood in 2010. She began divorce proceedings against him in August 2013 on the grounds of unreasonable behaviour. A decree nisi was granted in May 2014. He lived in Hersham before being sent to prison.
He was arrested in December 2012 by Metropolitan Police officers as part of Operation Yewtree an investigation which was set up to investigate child sexual abuse committed by DJ Jimmy Savile who died in 2011, and by other people. In 2014, he was tried at Southwark Crown Court for 11 counts of indecent assault against teenage girls. On 28 April 2014 he was convicted of 8 counts. On 2 May 2014, he was sentenced to 8 years imprisonment and is now incarcerated at HM Prison Littlehey in Cambridgeshire. He collapsed in his cell and was taken to hospital, where he died of a heart attack.
Jack Ramsay
John T. "Jack" Ramsay (February 21, 1925 – April 28, 2014), also known as "Dr. Jack", was an American basketball coach. He coached Saint Joseph's Hawks from 1955 until 1966, Philadelphia 76ers from 1968 until 1972, Buffalo Braves from 1972 until 1976, Portland Trail Blazers from 1976 until 1986 and Indiana Pacers from 1986 until 1988. He entered the Naismith Memorial Basketball Hall of Fame in 1992. He was born in Philadelphia, Pennsylvania.
Ramsay died in his sleep from cancer on the night of April 27, 2014. He was 89.
Birthday Girl is a 2001 British-American crime-thriller movie. It is set in St Albans, Hertfordshire. It stars Nicole Kidman and Ben Chaplin. It is a bank clerk in St Albans who finds a Russian mail-order bride, Nadia, played by Kidman.
Harry Firth
Harry L. Firth (18 April 1918 - 27 April 2014) was an Australian racing driver and team manager. Firth was a leading race and rally driver during the 1950s and 1960s and continued as an influential team manager with first the Ford works team and then the famed Holden Dealer Team (HDT) well into the 1970s. He was born in Orbost, Victoria.
Firth died from natural causes, aged 96.
Rolling and wheels in the natural world
There are two ways that natural and man-made things can use rotation to move around. One way is for the entire thing to roll. The other way is for part of the thing to turn while the rest does not, like a wheel or a propeller. Some living things move around by rolling, but no living things seem to use wheels. Biologists have written about the reasons for this. Writers of science fiction and fantasy have invented many animals with wheels.
Wheels are a very useful technology for people. Many technologies that people use are also found in nature, like wings and lenses.
It may seem strange, then, that wheels have never evolved in nature, but there are two reasons for this. First, there are natural limits to what kinds of things can exist in nature. Living things change slowly over time, a process called evolution by natural selection. This process can create many different answers to a problem, but it can't always create every answer that can be imagined. Also, the ways that new living things build themselves (a process called developmental biology) can't always create every kind of part that can be imagined. Second, wheels are sometimes less useful than other ways of moving, like walking, running, or slithering like a snake. For the same reason, some groups of people in the past have given up using wheels completely.
Some living things move around by rolling. These are not true examples of wheels, because the whole organism rotates, without any parts that stay still, like an axle.
Some kinds of animals form their bodies into a circle. In some cases, they do this to protect themselves, and in some cases they do it to be able to roll. Animals that do this include some caterpillars, tiger beetle larvae, myriapods, mantis shrimp, and salamanders. Other animals form into a ball instead. These animals include pangolins, hedgehogs, armadillos, the armadillo Lizard, isopods, the wheel spider, and fossilized trilobites. These animals may roll "passively", meaning they are pushed by gravity or wind, or "actively", meaning they push themselves by changing their shape. Tumbleweeds are a part of a plant that grows above the ground. Tumbleweeds break off from their roots and roll in the wind in order to spread their seeds.
Dung beetles form round balls of animal feces. They roll these balls with their bodies. Although the ball rolls instead of the beetle, the beetles have many of the same problems as rolling animals.
A kind of skin cell called a keratinocyte moves itself by rolling, as part of the process of healing.
A kind of tiny animal called a rotifer uses a ring of cilia (small hair-like parts) moving in rhythm to move and feed itself. The word "rotifer" in Latin means "having wheels", but rotifers do not actually have any parts that rotate.
No known multicellular organism (an organism made of many cells) can spin part of its body while keeping the rest of its body still. However, there are at least two examples of rotating parts used by cells. One example is a molecule called ATP synthase. ATP synthase is used to store and move energy. For example, it is used in the processes of photosynthesis (a way of storing energy from the sun) and oxidative phosphorylation (a way of releasing stored energy). ATP synthase is similar to flagellar motors, which are talked about below. Biologists (scientists who study life) think that ATP synthase is an example of modular evolution. In modular evolution, two parts with different jobs join together and pick up a new job.
The only known example in nature of a part that can spin all the way around to push an organism is the flagellum. The flagellum is a tail used like a propeller to push single-celled prokaryotes. The bacterial flagellum is the best known example. About half of all known bacteria have at least one flagellum. This means that rotation may actually be the most common way of moving around found in nature.
At the bottom of the bacterial flagellum, where it meets the cell membrane, a motor protein acts as an engine. This engine gets its power from proton motive force, the flow of protons (hydrogen ions) across the cell membrane. This is caused by a concentration gradient (a difference in the number of protons on each side of the membrane) created by the cell's metabolism. (Bacteria called "Vibrio" use two kinds of flagella, one of which is powered by sodium ions instead.) Flagella are very efficient, meaning not much energy is wasted. They can push bacteria as fast as 60 times their length every second. The motor at the bottom of the flagellum has a similar structure to ATP synthase. Bacteria called spirillum have twisted bodies with flagella on both ends. Spririllum bacteria spin around as they move.
A kind of organism called archaea, which are different from bacteria, also use flagella powered by rotating motor proteins. The two kinds of flagella evolved from different parts. Eukaryotic cells are a more complex kind of cell found in plants and animals. Some of these cells also have flagella called cilia, but these flagella do not rotate at the bottom. Instead, they bend so that the tip of the flagella moves in a circle.
The science of evolution can help to explain why multicellular organisms have not developed wheels. To put it simply, a complex structure (one made of several parts working together) can't evolve unless its early, unfinished form helps the organism to live and to have children.
In the modern science of evolution, adaptations (changes that affect the fitness of an organism) appear slowly, over many generations, by means of natural selection. Because of this, genetic changes usually only spread in a population if they do not lower the fitness of individuals. Neutral changes (changes that don't raise or lower fitness) can spread by genetic drift. In some cases, changes that lower fitness can spread, but large changes that take many steps can only spread if each of the steps raises fitness. The biologist Richard Dawkins describes the situation this way:
In this metaphor, fitness is a landscape, where useful traits are peaks and harmful ones are valleys. Wheels may be a very useful peak, but the valley around that peak is too low or too wide for the gene pool (the set of genes in the population) to move to it by genetic drift or natural selection. Stephen Jay Gould points out that evolution can only build with parts that are already available. He writes that, "wheels work well, but animals are debarred [(prevented)] from building them by structural constraints [(limits)] inherited as an evolutionary legacy."
Natural selection therefore explains why wheels have not appeared. A wheel without one or more of its important parts would probably not help an organism very much. However, the same is not true for the flagellum discussed above. As the flagellum evolved, different parts of other structures were used for a new purpose. The part that is now a rotating motor, called a basal body, may have evolved from a part that was used by bacteria to inject poisons into other cells. This use of existing parts is called "exaptation".
The biologist Robin Holliday has written that, because there are no living things with wheels, creationism and intelligent design (stories of life that claim an intelligent creator) are less likely to be right. Holliday argues that an intelligent creator, free from the limits of evolution, would use wheels in any place they would be useful.
People have found it fairly easy to build wheeled systems, even complex ones, and they have been able to solve problems of power transmission (moving energy from one place to another) and friction. However, the ways new organisms build themselves are very different from the ways humans build things. It is not clear that the processes of life would be able to make a wheel. The reasons for this are talked about below.
The greatest barrier to many-celled organisms with wheels is the interface (meeting point) between the parts that move and the parts that stay still. Wheels, or wheels and axles, need to be able to turn freely relative to the rest of the organism. Animal joints have a limited range of motion (the angle they can move), but wheels need to be able to turn through any angle without needing to be turned back. Because of this, wheels can't be attached to the axle or shaft that they turn on. No true many-celled organism is known to grow solid tissues or organs that are not attached to the rest of the organism.
To drive a wheel (that is, to make it turn), something must put a torque (twisting force) on it. For machines made by people, this torque is usually made by a motor. There are many kinds of motors, such as electric motors, turbines, and steam engines. Torque can also come from a person, as with a bicycle. In animals, movement is usually caused by skeletal muscles. These muscles get energy by metabolizing (breaking down) the nutrients in food. Skeletal muscles are attached with connective tissue to the bones they move, so they would not be useful for driving a wheel directly. Also, animals use their muscles in cycles - joints move in one direction, then the other, instead of moving in one direction constantly. Large animals cannot gain speed very quickly, because it is more difficult for muscles to pull against a large inertia (the resistance of a heavy object to movement).
In most machines, a lubricant (like oil or grease) or a bearing is used to limit friction (rubbing) between moving parts. Keeping friction down is important for limiting wear damage to the parts, and for keeping the parts from getting too hot. The faster the parts move, or the more force between them, the more important it is to reduce friction. In animal joints like the human knee, friction is reduced with a tissue called cartilage that has a low coefficient of friction, and a lubricating fluid called synovial fluid that has a low viscosity (resistance to flowing). Gerhard Scholtz, a professor at the ("Institute for Biology and Comparative Zoology") at Humboldt University of Berlin, has written that a similar lubricating fluid or material from dead cells could help an animal wheel to turn freely, but something like this has never been seen in nature.
Another problem is the flow of materials to and from a living wheel. If the tissues that form the wheel are living, then they must receive oxygen and nutrients and have wastes taken away in order to continue metabolism (the process of using energy to maintain functioning). A normal animal circulatory system (the network of tubes that allow blood to flow), would not be able to provide for the necessary flow of materials. Without blood flowing, materials would have to diffuse to and from the wheel. Diffusion is limited by partial pressure and surface area, by a rule called Fick's law of diffusion. For large animals, diffusion would not be enough to keep tissues alive. Instead of a living wheel, a wheel could be made of dead material like keratin, which makes up hair and nails.
In some environments, wheels are simply not as good as limbs for getting around. So it may be that, even if it were possible for wheels to evolve, they would not be found often in nature. In fact, given the limits of wheels, the main question can be turned around: instead of asking ""Why doesn't nature use wheels?"", the question becomes ""Why don't people build more machines with limbs?"" In engineering, wheels are often used instead of limbs, because limbs are more complex to design and control—not because wheels necessarily do the job better.
On hard, flat ground, like paved roads, hard wheels are more energy efficient than other ways of moving around. However, wheels are not as efficient (they take more energy to move) on soft surfaces, like soils, because they have to deal with "rolling resistance". In rolling resistance, a vehicle loses energy as the shape of the wheel and the surface are deformed (changed), and the surface pushes back against the wheel. Smaller wheels have to deal with more resistance for their size than larger wheels. Softer surfaces deform more than hard surfaces, and they don't come back to their starting shape as well. This causes greater resistance. Compared to concrete, the resisting force on medium-hard soil can be five to eight times greater, and on sand it can be ten to fifteen times greater. While wheels must deform the surface along their entire path, limbs only cause a small deformation at the point that the foot touches the ground.
Rolling resistance is also the reason that some human civilizations didn't use wheels. During the Roman Empire, wheeled chariots were common in the Middle East and North Africa. However, when the Empire fell, wheels became less useful to the local people, who turned to camels to transport goods in the sandy desert climate. Stephen Jay Gould wrote about this strange fact of history in his book "Hen's Teeth and Horse's Toes". He wrote that without maintained roads, camels needed less human power and water than a cart pulled by oxen.
When moving in water, rotating mechanisms are more efficient only when the "Reynolds number" of the flow is very low. The Reynolds number is a way to describe the behavior of a flow—in a flow with a low Reynolds number, like those in which bacteria move, viscosity is the most important effect to consider. In flows with high Reynolds numbers, inertia is the most important effect, and mechanisms that "oscillate", or move back and forth, are more efficient. Although ship propellers usually have an efficiency near 60%, and aircraft propellers around 80% (up to 88% in the human-powered "Gossamer Condor"), oscillating foils like fish tails and bird wings can be as efficient as 96%−98%.
Wheels can slip, meaning they fail to get a grip, on loose or slippery ground. Slipping wastes energy, and can lead to loss of control or becoming unable to move. This happens to cars on mud, ice, and snow. Where wheels have this problem, people sometimes use other mechanisms instead. In the logging industry, vehicles with legs are sometimes used to reach areas that are more difficult than what wheels can deal with. Vehicles with tracks, like tanks, don't slip as much as vehicles with wheels, because they have a larger area touching the surface. However, vehicles with tracks often have a larger turning radius than wheeled vehicles, meaning they take more space to turn. They are also less efficient, and more complex to build.
The engineer Mieczysław G. Bekker showed that in natural terrain, small obstacles are much more common than large ones. This is called a "log-normal" distribution. This means that obstacles are a problem for wheeled vehicles of all sizes. The main ways of dealing with obstacles are to go around them, and to go over them.
The most common types of steering do not include separate articulation (joints for bending) for each wheel, so they have a limited turning radius. This limits how well these kinds of vehicles can move around where there are a large number of obstacles.
Michael LaBarbera of the University of Chicago shows the limited turning radius of wheels by comparing humans walking with humans in wheelchairs. Jared Diamond points out that most examples of rolling in nature are found in wide open, hard terrain. This includes the use of rolling by dung beetles and tumbleweeds.
Wheels are bad at dealing with vertical (upright) obstacles, especially obstacles about the same size as the wheel itself. If a vehicle or animal can move its center of mass, then the largest vertical obstacles that can be climbed are half as high as the wheel. If the center of mass cannot be moved, the highest obstacle that can be climbed is one eighth to one quarter the height of the wheel.
Also, without joints, a wheeled vehicle can become stuck (unable to move) on top of an obstacle, with the obstacle between the wheels so they don't touch the ground. Limbs, unlike wheels, are useful for climbing, and can deal with difficult terrain.
For wheels without joints, climbing obstacles will cause the body of the vehicle to tilt. If the weight of the vehicle moves outside of the wheels, the vehicle can tip over because of "static instability". At high speed, a vehicle's inertia can cause it to become "dynamically unstable". This means it can be tipped over by a smaller obstacle, or simply by turning or changing speed too quickly. Without jointed limbs, it can be impossible to recover from being tipped over.
Limbs used by animals to move over terrain are often also used for other purposes, such as holding and manipulating things, climbing, swinging from branches, swimming, digging, jumping, throwing, kicking, and grooming. Without joints, wheels are not as useful as limbs for these jobs.
The hoop snake is an animal described in legend in the United States and Australia. The snake is said to hold its tail in its mouth and roll like a wheel towards its victims. The Japanese Tsuchinoko is a similar legendary animal.
The 1944 science fiction short story "Arena", by Fredric Brown, includes a telepathic (mind-reading) alien called an "Outsider". The Outsider is shaped like a ball and moves by rolling. A 1967 "" episode with the same name was based on the story. A 1964 episode of "The Outer Limits" called "Fun and Games" may have been based on the same story. Neither television episode included a rolling animal.
The Dutch artist M. C. Escher invented an animal that he named "Pedalternorotandomovens centroculatus articulosus". This animal was able to roll itself forward like a wheel. Escher drew the animal in his 1951 picture (also known by the English title "Curl-up").
A 1956 Scrooge McDuck comic by Carl Barks, "Land Beneath the Ground!", included "Terries" and "Fermies", characters who move from place to place by rolling like a bowling ball. The Terries and Fermies have turned their rolling into a sport, causing earthquakes in the process.
"Tuf Voyaging", a 1986 science fiction novel by George R. R. Martin, includes a type of alien called a "Rolleram", which kills its victim by rolling over it.
In the "Sonic the Hedgehog" video game series, the main character Sonic and his sidekick Tails move by rolling. The "Sonic the Hedgehog" series first appeared in 1991.
The 1995 short story "Microbe", by Kenyon College biologist and feminist science fiction writer Joan Slonczewski, is about a trip to explore an alien world, where the plant and animal life is entirely made of doughnut-shaped organisms.
L. Frank Baum's 1907 children's book "Ozma of Oz" includes human-like creatures with wheels instead of hands and feet, called "Wheelers".
The 1968 novel "The Goblin Reservation" by Clifford D. Simak includes an intelligent kind of alien that uses natural wheels.
Piers Anthony's 1977 book "Cluster" and its sequels (the later books in the same series) include a type of aliens called Polarians. The Polarians move around by holding and balancing on a large ball. The ball is a living part of the Polarian's body that can be removed temporarily.
David Brin's "Uplift" Universe includes a kind of wheeled alien called the G'Kek. The G'Kek are described in the 1995 novel "Brightness Reef". In the 1996 novel "Infinity's Shore", the G'Kek are said to look like "a squid in a wheelchair." They suffer from arthritis in their axles as they become old, especially when living in an environment with high gravity.
A 1997 novel in the Animorphs series, "The Andalite Chronicles", includes a kind of aliens called Mortrons. The Mortrons are made of two separate living parts: a yellow and black bottom half with four wheels, and a long, red head with sharp teeth and hidden wings.
The 2000 novel "The Amber Spyglass", by English author Philip Pullman, includes a type of alien known as the Mulefa. The Mulefa have diamond-shaped (◊-shaped) bodies with one leg at the front and back and one leg on each side. The Mulefa use large, disc-shaped seed pods as wheels. They hold the pods on axles made of bone on their front and back legs, while pushing themselves with their side legs. The Mulefa and the seed pod trees have a symbiotic relationship, or a relationship that helps both sides: the Mulefa use the seed pods as wheels, and the seed pod trees depend on the rolling to crack open the pods and allow the seeds to spread.
In the 2000 novel "Wheelers", by English mathematician Ian Stewart and biologist Jack Cohen, a kind of alien called "blimps" can grow machines called "wheelers", which use wheels to move.
The 2009 Disney children's television series Jungle Junction includes jungle animals with wheels instead of legs. One of these animals, "Ellyvan", is a hybrid (a combination) of an elephant and a van. These animals move around their home on highways.
Idris Sardi
Idris Sardi (June 7, 1938 – April 28, 2014) was an Indonesian violinist. His career lasted for nearly 50 years until retiring in 2013 because of ill health. Sardi was born to Mas Sardi, an Indonesian composer, and Hadidjah, an Indonesian actress.
Sardi died at Meilia Hospital in Cibubur, Indonesia from an illness. He was 75 years old.
Cordial (candy)
June Angela
2011 Tuscaloosa–Birmingham tornado
The 2011 Tuscaloosa–Birmingham tornado involved several strong tornadoes in Alabama. It took place on Wednesday, April 27, 2011. The tornado was a violent EF4 multiple vortex event which caused over $2 billion in damage.
Early reports indicated 65 people were killed, with over 1,000 injured. However, this was revised to 64 deaths and more than 1,500 injuries.
Donald Sterling
Donald Tokowitz Sterling (born April 26, 1934) is an American business magnate and former attorney.
Sterling was born in Chicago, Illinois. He was raised in Los Angeles, California. Sterling studied at the University of California, Los Angeles and at Southwestern Law School. He was raised as Jewish.
He was the owner of the Los Angeles Clippers in the National Basketball Association (NBA). Sterling bought the Clippers in 1981 for $12.5 million, and as of 2014, the team is valued at $575 million by "Forbes" magazine, ranking them 18th out of 30 teams. At 33 seasons of ownership (1981 to present), Sterling was the longest-tenured owner in the NBA since the death of Los Angeles Lakers majority owner Jerry Buss on February 18, 2013 up until his suspension on April 29, 2014.
Sterling was married to Rochelle Stern. They had six children. He lives in Los Angeles, California.
On April 25, 2014, "TMZ Sports" released what it said is an April 9, 2014 audio recording of a conversation between Sterling and V. Stiviano. According to TMZ, Sterling and Stiviano argued in regards to a photo Stiviano posted on Instagram in which she posed with Magic Johnson. In the audio recording, Sterling allegedly tells Stiviano: "It bothers me a lot that you want to broadcast that you’re associating with black people." On April 29, 2014, the University of California, Los Angeles announced that it was rejecting a $3 million gift from Sterling. On April 29, 2014, Sterling was banned from the NBA for life and fined $2.5 million by the NBA after recordings of him making racist comments were made public.
In 2012, Sterling began treatment for prostate cancer. In May 2014, it was announced that Sterling was in the early developing stages of Alzheimer's disease.
Dean Acheson
Dean Gooderham Acheson (pronounced ; April 11, 1893 – October 12, 1971) was an American statesman and lawyer. He was a member of the Democratic Party.
Acheson was born in Middletown, Connecticut. He studied at Yale College and at Harvard Law School. He married Alice Stanley in 1917.
Acheson served as the 51st United States Secretary of State under President Harry S. Truman. He served as Secretary of State from January 1949 to January 1953. He helped defend America's foreign policy during the break of the Cold War.
Acheson's most famous decision was convincing President Truman to intervene in the Korean War in June 1950. He also persuaded Truman to dispatch aid and advisors to French forces in Indochina, though in 1968 he finally counseled President Lyndon B. Johnson to negotiate for peace with North Vietnam.
During the Cuban Missile Crisis, President John F. Kennedy called upon Acheson for advice, bringing him into the executive committee (ExComm), a strategic advisory group.
Acheson and his wife Alice had three children; David, Jane, and Mary. He remained married to Alice until his death in 1971. He retired shortly after 1955.
Acheson was awarded the Presidential Medal of Freedom in 1964 by President Lyndon B. Johnson. He also won a Pulitzer Prize for History in 1970.
Acheson died in Sandy Spring, Maryland from a massive stroke. He was 78 years old. He was survived by his two surviving children, David and Mary. He was buried at Oak Hill Cemetery in Washington, D.C..
Sandy Spring, Maryland
Sandy Spring, Maryland is an unincorporated community in Montgomery County, Maryland.
Overbrook, Kansas
Overbrook is a city in Osage County, Kansas.
Little Talks
"Little Talks" is a 2011 debut single by Of Monsters and Men. The song came from the album "My Head is an Animal".