Detection.

A 2009 study found that there are recognisable traits that can often be observed when a player is diving. They are:

Punishment.

The game's rules state that "attempts to deceive the referee by feigning injury or pretending to have been fouled (simulation)", must be sanctioned as unsporting behaviour which is misconduct punishable by a yellow card. The rule changes are in response to an increasing trend of diving and simulation.

Europe.

In 2009, UEFA made the decision to ban Arsenal forward Eduardo da Silva for a dive during a Champions League qualifier against Celtic. Eduardo initially received a penalty after referee Manuel Mejuto González believed Eduardo had been fouled by Celtic goalkeeper Artur Boruc, but video evidence showed there was no contact between Eduardo and Boruc. Eduardo scored the subsequent penalty, with the goal putting Arsenal 3–0 up on aggregate. Arsenal manager Arsène Wenger claimed the ban, which was to last two games, was "a complete disgrace and unacceptable", as it singled out Eduardo as a cheat, something which UEFA would be unable to prove. The ban was subsequently overturned on appeal, with Eduardo saying he was pleased UEFA had "arrived at the truth" as he was a "fair player" and was "not the type of player who needs to be dishonest".  In 2011, Rangers player Sone Aluko was banned for two games for simulation by the Scottish FA. During a game against Dunfermline Athletic, Aluko won a penalty which was converted by Nikica Jelavić and which proved to be the decisive goal. Dunfermline manager Jim McIntyre claimed it was "never a penalty" as there was no contact, and that Aluko was "obviously trying to get his team into a lead". Former referee Kenny Clark said that, while there was contact, it was "not enough to cause a man to spill a pint in a pub far less to fall over". After a club appeal had failed, Rangers manager Ally McCoist said he was "shocked and extremely angry" at the decision of the panel, which included former referee Jim McCluskey, who McCoist was critical of in particular, saying "his decision making hasn't improved any since he stopped refereeing".  In November 2017, Everton player, Oumar Niasse became the first player to be banned by the Football Association for diving. He received a two-match ban for the offence while playing against Crystal Palace.

North America.

Major League Soccer in the United States began implementing fines and suspensions for the 2011 season for simulation through its Disciplinary Committee, which reviews plays after the match. On 24 June 2011, MLS penalised D.C. United forward Charlie Davies with a US $1,000 fine as the Disciplinary Committee ruled he "intentionally deceived the officials and gained an unfair advantage which directly impacted the match" in a simulation that occurred in a match against Real Salt Lake on 18 June 2011.  On 29 July 2011, the Disciplinary Committee suspended Real Salt Lake forward Álvaro Saborío one game and fined him US $1,000 for a simulation in a game against the San Jose Earthquakes on 23 July 2011. Officials noted the simulation resulted in Earthquakes defender Bobby Burling being sent off on the simulation, and the warning from MLS that fines and suspensions will increase for simulation being detected by the Disciplinary Committee. Furthermore, suspensions caused by players being sent off by another player's simulation can be rescinded. For example, if A2 is assessed a red card for a foul when B3 had created a simulation to make it seem A2 committed a hard foul when it was a simulation, the Disciplinary Committee can rescind the red card and suspension for A2.

Oceania.

In all football leagues (including youth) a player who dives intently will be subject to a warning or yellow card if caught in a match. If a match is reviewed and a player gets caught they may get a 1 match suspension however if it's the 3rd time in a season they will get a 5 match suspension or until the end of that season (what ever is longer) OFC also has the right to ban players who intentionally dive to get a penalty or free kick. These rules are effect in club matches and international friendly (between two ofc countries)

Diving as deceptive behaviour.

Recently, researchers studying signalling in animals examined diving in the context of communication theory, which suggests that deceptive behaviour should occur when the potential payoffs outweigh the potential costs (or punishments). Their aim was to discern when and where diving is likely to occur, with the aim of identifying ways to stop it.  The researchers watched hundreds of hours of matches across 6 European professional leagues and found that diving is more likely to occur a) near the offensive goal and b) when the match is tied. None of the 169 dives seen in the study were punished.  It was also found that diving was more common in leagues where it was rewarded most – meaning that the more often players were likely to get free kicks or penalties out of a dive, the more often they dived. This suggests that the benefits of diving are far outweighing the costs, and the only way to reduce diving in football is by increasing the ability of referees to detect dives and by increasing the punishment associated with them.  "Some progressive professional leagues, such as the Australian A-League and the American MLS have already started handing down punishments for players found guilty of diving. This is the best way to decrease the incentive for diving," says Dr. Robbie Wilson of the soccerscience lab that conducted the study.  Some have referred to simulation as a menace to footballers with real, sometimes life-threatening, injuries or conditions. On 24 May 2012, English FA referee Howard Webb spoke to a FIFA medical conference in Budapest about the importance of curbing simulation in football, as players feigning injury could put players with serious medical issues in jeopardy. Earlier that year, he had to deal with the collapse of Fabrice Muamba, who suffered cardiac arrest during an FA Cup match.

Diving reputation.

Repeated accusations of diving have resulted in certain players acquiring the reputation of being a "diver".  Over the years, players who have earned the reputation of being divers (by ranking in published or broadcast lists, fines by the league, or news articles and interviews) include:

In association football, diving is an attempt by a player to gain an unfair advantage by falling to the ground and possibly feigning an injury, to give the impression that a foul has been committed. Dives are often used to exaggerate the amount of contact present in a challenge. Deciding on whether a player has dived is often very subjective, and one of the most controversial aspects of football discussion. Players do this so they can receive free kicks or penalty kicks, which can provide scoring opportunities, or so the opposing player receives a yellow or red card, giving their own team an advantage. Diving is also known as simulation (the term used by FIFA), Schwalbe (German for swallow), and, in the U.S., flopping.

-{zh-hans:假摔,香港称为插水;zh-hk:插水,中国大陆称为假摔;zh-tw:假摔,香港称为插水;}-(英语:Diving 或 英语:simulation)是一个足球术语。意思是指一个球员为了博取任意球或十二码等罚球,而假装被对手侵犯倒地,由于不少球员假装被侵犯时,会自行跌倒在地,动作近似跳水运动的入水动作,故英文称为Diving。


Formula.

A popular formula to convert "f" hertz into "m" mels is:

History and other formulas.

There is no single mel-scale formula. The popular formula from O'Shaughnessy's book can be expressed with different logarithmic bases:  The corresponding inverse expressions are:  There were published curves and tables on psychophysical pitch scales since Steinberg's 1937 curves based on just-noticeable differences of pitch. More curves soon followed in Fletcher and Munson's 1937 and Fletcher's 1938 and Stevens' 1937 and Stevens and Volkmann's 1940 papers using a variety of experimental methods and analysis approaches.  In 1949 Koenig published an approximation based on separate linear and logarithmic segments, with a break at 1000 Hz.  Gunnar Fant proposed the current popular linear/logarithmic formula in 1949, but with the 1000 Hz corner frequency.  An alternate expression of the formula, not depending on choice of logarithm base, is noted in Fant (1968):  In 1976, Makhoul and Cosell published the now-popular version with the 700 Hz corner frequency. As Ganchev et al. have observed, "The formulae [with 700], when compared to [Fant's with 1000], provide a closer approximation of the Mel scale for frequencies below 1000 Hz, at the price of higher inaccuracy for frequencies higher than 1000 Hz." Above 7 kHz, however, the situation is reversed, and the 700 Hz version again fits better.  Data by which some of these formulas are motivated are tabulated in Beranek (1949), as measured from the curves of Stevens and Volkmann:  A formula with a break frequency of 625 Hz is given by Lindsay & Norman (1977); the formula doesn't appear in their 1972 first edition:  For direct comparison with other formulae, this is equivalent to:  Most mel-scale formulas give exactly 1000 mels at 1000 Hz. The break frequency (e.g. 700 Hz, 1000 Hz, or 625 Hz) is the only free parameter in the usual form of the formula. Some non-mel auditory-frequency-scale formulas use the same form but with much lower break frequency, not necessarily mapping to 1000 at 1000 Hz; for example the ERB-rate scale of Glasberg & Moore (1990) uses a break point of 228.8 Hz, and the cochlear frequency–place map of Greenwood (1990) uses 165.3 Hz.  Other functional forms for the mel scale have been explored by Umesh et al.; they point out that the traditional formulas with a logarithmic region and a linear region do not fit the data from Stevens and Volkmann's curves as well as some other forms, based on the following data table of measurements that they made from those curves:

Criticism.

Stevens' student, Donald D. Greenwood, who had worked on the mel scale experiments in 1956, considers the scale biased by experimental flaws. In 2009 he posted to a mailing list,

The mel scale, named by Stevens, Volkmann, and Newman in 1937, is a perceptual scale of pitches judged by listeners to be equal in distance from one another. The reference point between this scale and normal frequency measurement is defined by assigning a perceptual pitch of 1000 mels to a 1000 Hz tone, 40 dB above the listener's threshold. Above about 500 Hz, increasingly large intervals are judged by listeners to produce equal pitch increments. As a result, four octaves on the hertz scale above 500 Hz are judged to comprise about two octaves on the mel scale. The name mel comes from the word melody to indicate that the scale is based on pitch comparisons.

梅尔刻度(又称Mel尺度,英语:Mel scale)是一种非线性刻度单位,表示人耳对等距音高(pitch)变化的感官,基于频率定义,由、 和Newman于1937年命名。


History.

1993–1995: Origins.

Much like its competitor UPN, The WB was summoned in reaction primarily to the Federal Communications Commission (FCC)'s then-recent deregulation of media ownership rules that repealed the Financial Interest and Syndication Rules, and partly due to the success of the Fox network (which debuted in October 1986, nine years before The WB launched) and first-run syndicated programming during the late 1980s and early 1990s (such as "Baywatch", "" and "War of the Worlds"), as well as the erosion in ratings suffered by independent television stations due to the growth of cable television and movie rentals. The network can also

1995–1997: Beginnings.

The WB Television Network premiered on January 11, 1995, with the inaugural episode of "The Wayans Bros." (a sitcom starring comedians Shawn and Marlon Wayans) as its first program. The classic Warner Bros. cartoon character Michigan J. Frog appeared on-air as the network's official mascot (with animator Chuck Jones, in person, drawing him out after Bugs Bunny and Daffy Duck argued about who should launch The WB during the network's premiere), and would remain as part of the network's branding in one form or another until 2005. Much of the network's branding was based around Warner Bros. locations and characters: the

1997–2000: Courting the teen market.

The WB first began to experience success with "Buffy the Vampire Slayer" (a series based on the 1992 film of the same name), which became a hit with critics when it premiered as a mid-season replacement in March 1997. It debuted with the highest Monday night ratings in the network's history, attracting not only new teenage viewers, but new advertisers as well.  Inspired by "Buffy"s success, The WB intentionally shifted the focus of its programming, trying to capture what it perceived to be a heavily fragmented market by marketing to the under-courted teen demographic. While the Fox network, the previous destination for teen television (with shows such as "Beverly Hills, 90210" and "Parker Lewis Can't Lose"), began to court older audiences with shows such as "Ally McBeal", The WB began to craft its identity with programs targeted at teenagers. The network's breakout hit and, arguably, its signature series was "Dawson's Creek", which debuted in January 1998 to what were then the highest ratings in the network's history (and made stars out of its four principal actors, James Van Der Beek, Michelle Williams, Joshua Jackson and Katie Holmes). It

2000–2003: Broadening the focus.

As the teen boom of the late 1990s began to wane, The WB attempted to broaden the scope of its primetime lineup. Although teen-oriented fare like "Popular" and "Roswell" had premiered to strong ratings, both series saw serious ratings erosion in their sophomore seasons, leading the network to cancel them both ("Roswell", like "Buffy the Vampire Slayer", would end up being revived by rival network UPN). Meanwhile, even though ratings for "7th Heaven", "Buffy" and "Charmed" remained consistent, viewership for flagship series such as "Felicity" and "Dawson's Creek" began sagging. The network realized that it could no longer rely merely on the tastes of young teenage girls, and thus began moving

2003–2006: Decline.

Despite some early success, the network struggled to shift its focus from the female 12–24 demographic to the broader 12–34 range, in its attempt to attract a broader young adult audience. In 2005, the network retired Michigan J. Frog, as the network's trademark mascot. The WB's president of entertainment at the time, David Janollari, explained in July 2005 at the network's summer press tour that "[Michigan] was a symbol that perpetuated the young-teen feel of the network. That's not the image we [now] want to put to our audience."  Still, the move did not seem to help the network. The period from 2003 to 2005 produced only three viable new series, the teen-oriented drama "One Tree Hill", social experiment reality competition "Beauty and the Geek" and fantasy drama "Supernatural" (all of which ultimately moved to successor network The CW), and even still their ratings paled

2006: Network closure.

On January 24, 2006, CBS Corporation and Warner Bros. Entertainment announced plans to shut down both UPN and The WB and partner to launch a new broadcast television network that would include series from both soon-to-be predecessor networks, known as The CW. Over the next eight months, it was to be seen which shows from the two networks would cross over to The CW, as well as which stations aligned with either UPN or The WB would become future affiliates of the new network. In the end, "7th Heaven", "Beauty and the Geek", "Gilmore Girls", "One Tree Hill", "Reba", "Smallville" and "Supernatural" were chosen to move from The WB to The CW for its inaugural 2006–07 fall schedule. "7th Heaven" and "Reba" were originally canceled after the 2005–06 season, but were ultimately renewed at the last minute with 13-episode deals (the former show was later given

2008–2013: Internet streaming.

Warner Bros.' television arm planned on resurrecting The WB brand in the form of a website at TheWB.com, the website domain used for the official site of the broadcast network. The site streamed episodes of series that were broadcast during The WB Television Network's 1995–2006 run, including "Gilmore Girls", "Smallville", "Everwood", "Buffy the Vampire Slayer", "Dawson's Creek", "One Tree Hill", "Roswell" and "What I Like About You". The new incarnation of the TheWB.com began in beta testing on April 28, 2008, and officially launched on August 27. The site – whose business model resembled that of free-to-stream services such as Hulu – was ad-supported and geared primarily to women ages 15–39. In addition to older full-length series (among which also included "All of Us", "Hangin' with Mr. Cooper", "Martin", "Jack & Bobby" and "Veronica Mars"), the website featured original serialized web content including short series and vignettes from such well-known television producers as Josh Schwartz and McG, including "Sorority Forever", "Pushed", "Rockville, CA", "The Lake" and "Children's Hospital" (the latter's popularity was sustained enough to receive a run and eventual move to cable television as a regular series on Cartoon Network's Adult Swim). Each of these 10-episode programs ran for five minutes.  Many other well-known Warner Bros.-produced series that did not air on The WB, including "Friends" and "The O.C.", were also made available on the site. However, the website did not include episodes of two of The WB's most

Programming.

Many, though not all, of The WB's programming during its eleven-year run as a television network was produced by corporate cousin Warner Bros. Television. The network's schedule during its first two seasons – the 1995 midseason (when it inaugurated its initial Wednesday lineup) and the first half of the 1995–96 season (when the network expanded its programming to Sundays) – consisted entirely of sitcoms; the first drama series to debut on the network was the primetime soap "Savannah", which debuted in February 1996 and ran for two seasons until its cancellation in February 1997. The WB's first reality series was the U.S. adaptation of "Popstars", which ran for two seasons from 2001 to 2003.  In addition to live-action programs, the network has experimented with primetime animated series; "Pinky and the Brain" was the first such series, airing as part of the network's Sunday lineup from September 1995 to July 1996, before moving exclusively to the Kids' WB Saturday lineup due to low ratings in its prime time slot. Most of the animated projects that aired afterward were adult animation series; the last such attempts being "The Oblongs" (running for one season in 2001, and was later revived on corporate sister Cartoon Network's Adult Swim block) and "The PJs" (which moved to the network in 2000 following its cancellation by Fox, and ran for only one additional season on The WB).  The WB also occasionally aired regularly scheduled repeat episodes of first-run series airing on other nights throughout the television season intermittently throughout its history; "Sister, Sister" was the first WB series to receive this treatment, with repeats of the sitcom's first two seasons (which originally aired on ABC) from August 1995 to August 1996, in addition to the first-run episodes it aired on Wednesday nights (this marked the first time that a network aired reruns as part of its regular schedule – outside of the summer months – since December 1993, when NBC removed repeats of "Classic Concentration" from its daytime lineup two years after that program's cancellation). From 1998 to 2000, the network also aired episode repeats from the first two seasons of "7th Heaven" during the first hour of its Sunday lineup under the title "7th Heaven Beginnings"; this concept was revived during the 2002–03 and 2003–04 seasons with "Smallville" and "Gilmore Girls" (which aired repeats from their early seasons under the respective titles "Smallville: Beginnings" and "Gilmore Girls: Beginnings"). Furthermore, from September 2002 until The WB ceased operations, the network ran a two-hour extension of its Sunday lineup (from 5:00 to 7:00 p.m. Eastern and Pacific Time), known as "EasyView", a block featuring week-behind episode rebroadcasts of select shows from the network's primetime schedule.  Out of all the network's series, "7th Heaven" – which by the time it ended, had become the longest-running family drama in television history – was the longest-running series ever to have aired on The WB, having run on the network for ten seasons from 1996 to 2006. The program was beaten by "Supernatural" as the longest-running series to originate on The WB in the 2017-18 season, when the latter series began its thirteenth season ("7th Heaven" ran for an additional season on The CW from 2006 to 2007; while "Supernatural" aired on The WB for one season from 2005 to 2006, before moving to The CW in September 2006, where it has aired since).

Differences between The WB and the "Big Four" networks.

Scheduling.

At the time of its shutdown, The WB ran only two hours of primetime network programming on Monday through Fridays and five hours on Sundays, compared to the three Monday through Saturday and four Sunday primetime hours offered by the Big Three networks (unlike The WB, UPN never carried any weekend primetime programming, though it did offer a movie package to its affiliates on weekend afternoons until September 2000, when the latter was replaced with a two-hour repeat block of UPN programs). This primetime scheduling allowed for many of the network's affiliates to air local newscasts during the 10:00–11:00 p.m. (Eastern and Pacific) time period.  The WB never ran network programming on Saturday nights – despite the fact that the network maintained a children's program block on Saturday mornings – allowing affiliates to run

Affiliate distribution.

The WB was the only English language broadcast network that historically did not have any owned-and-operated stations. Although Tribune Broadcasting maintained an ownership stake in The WB, its stations in the three largest television markets of New York City (WPIX), Los Angeles (KTLA) and Chicago (WGN-TV) were actually "affiliates" of the network since Tribune did not have a controlling ownership interest in the network to allow its stations to be constituted as O&Os (by 2005, Tribune owned 22.5% of the network, while Time Warner held the controlling 77.5% interest). Time Warner did not have a station group of its own at the time (and

News programming.

News programming on The WB's affiliates was similar to Fox stations at the time in that the quantity of newscasts varied from station to station. Roughly half of The WB's approximately 200 affiliates aired a local newscast in the 10:00–11:00 p.m. Eastern/Pacific (9:00–10:00 p.m. Central/Mountain) time slot at some point during or throughout their affiliations with the network. Fundamentally, the newscast schedules on WB affiliates varied considerably between stations compared to those affiliated with ABC, CBS, NBC and especially Fox. Most WB affiliates generally ran a two-hour morning newscast on weekdays and/or a half-hour or hour-long 10:00 p.m. newscast on Monday through Fridays only or all seven nights of the week; although there were a few larger market stations that maintained in-house news departments that also produced midday newscasts and had morning newscasts that began in the then-traditional 5:00–7:00 a.m. timeslot; early

Affiliates.

In 2005, The WB had an estimated audience reach of 91.66% of all U.S. households (equivalent to 90,282,480 households with at least one television set); the network was carried by 177 VHF and UHF stations in the United States. The WB was also available in Canada on cable and satellite providers through affiliates that are located within proximity to the Canada–US border (whose broadcasts of WB shows were subject to simultaneous substitution rules imposed by the Canadian Radio-television and Telecommunications Commission to protect program rights held by a domestically based network), and through two affiliates owned by Tribune Broadcasting (WPIX/New York City and KTLA/Los Angeles) that are classified in that country as superstations, as well as the superstation feed of Chicago affiliate WGN-TV.

Station standardization.

When The WB launched in 1995, the network began branding most of its affiliates with a combination of "WB" or "The WB," and the station's channel number. This meant that, for example, New York City affiliate WPIX and St. Louis affiliate KPLR-TV were both referred to as "WB11" (though WPIX branded as "The WB, Channel 11" until 1996, and KPLR as its pre-affiliation brand "St. Louis 11" until 1998). Fox originated such naming schemes, and CBS uses similar on-air branding for most of its owned-and-operated stations (NBC and ABC also utilize similar, but less extreme, naming schemes). While Fox and UPN mandated their respective branding schemes on all of their stations, The WB did not. Therefore, other WB affiliates opted to use non-standardized brandings: WGN-TV/Chicago branded as "WGN Channel 9" (or simply "WGN") with The WB's logo placed within the right curve of the station's "9 as an upside-down G" logo after the network launched,

The WB Television Network (commonly shortened to The WB and short for Warner Bros.) was an American television network first launched on broadcast television on January 11, 1995, as a joint venture between the Warner Bros. Entertainment division of Time Warner and the Tribune Broadcasting subsidiary of the Tribune Company, with the former acting as controlling partner. The network principally aired programs targeting teenagers and young adults between the ages of 12 and 34, with its Children's Division, Kids' WB, geared toward children ages 6 to 12. The common metonym of the network called "The Frog", referring to a former mascot Michigan J. Frog.

WB电视网(英语:The WB Television Network)是美国的一家电视台。于1995年1月11日开始播出。由华纳兄弟公司经营。2006年1月24日,CBS集团与华纳兄弟公司宣布将在秋季开播新的电视台The CW。2006年9月17日WB电视网停播,18日The CW开播。2008年4月28日,华纳兄弟开通了网络电视网站The WB,播出此台之前播出的节目。


History of the term.

The term "technocracy" is derived from the Greek words τέχνη, "tekhne" meaning "skill" and κράτος, "kratos" meaning "power", as in "governance", or "rule". William Henry Smyth, a California engineer, is usually credited with inventing the word "technocracy" in 1919 to describe "the rule of the people made effective through the agency of their servants, the scientists and engineers", although the word had been used before on several occasions. Smyth used the term "Technocracy" in his 1919 article "'Technocracy'—Ways and Means to Gain Industrial Democracy," in the journal "Industrial Management" (57). Smyth's usage referred to Industrial democracy: a movement to integrate workers into decision making through existing firms or revolution.  In the 1930s, through the influence of Howard Scott and the technocracy movement he founded, the term technocracy came to mean, 'government by technical decision making', using an energy metric of value. Scott proposed that money be replaced by energy certificates denominated in units such as ergs or joules, equivalent in total amount to an appropriate national net energy budget, and then distributed equally among the North American population, according to resource availability.  There is in common usage found the derivative term "technocrat". The word "technocrat" can refer to someone exercising governmental authority because of their knowledge, or "a member of a powerful technical elite", or "someone who advocates the supremacy of technical experts". McDonnell and Valbruzzi define a prime minister or minister as a technocrat if "at the time of his/her appointment to government, he/she: has never held public office under the banner of a political party; is not a formal member of any party; and is said to possess recognized non-party political expertise which is directly relevant to the role occupied in government". In Russia, the President of Russia has often nominated ministers based on technical expertise from outside political circles, and these have been referred to as "technocrats".

Precursors.

Before the term "technocracy" was coined, technocratic or quasi-technocratic ideas involving governance by technical experts were promoted by various individuals, most notably early socialist theorists such as Henri de Saint-Simon. This was expressed by the belief in state ownership over the economy, with the function of the state being transformed from one of pure philosophical rule over men into a scientific administration of things and a direction of processes of production under scientific management. According to Daniel Bell: "St. Simon's vision of industrial society, a vision of pure technocracy, was a system of planning and rational order in which society would specify its needs and organize the factors of production to achieve them." Citing the ideas of St. Simon, Bell comes to the conclusion that the "administration of things" by rational judgement is the hallmark of technocracy.  Alexander Bogdanov, a Russian scientist and social theorist, also anticipated a conception of technocratic process. Both Bogdanov’s fiction and his political writings, which were highly influential, suggest that he expected a coming revolution against capitalism to lead to a technocratic society.  From 1913 until 1922, Bogdanov immersed himself in the writing of a lengthy philosophical treatise of original ideas, "Tectology: Universal Organization Science". Tectology anticipated many basic ideas of systems analysis, later explored by cybernetics. In "Tectology", Bogdanov proposed to unify all social, biological, and physical sciences by considering them as systems of relationships and by seeking the organizational principles that underlie all systems.  Arguably, the Platonic idea of philosopher-kings represents a sort of technocracy in which the state is run by those with specialist knowledge, in this case, knowledge of the Good, rather than scientific knowledge. The Platonic claim is that those who best understand goodness should be empowered to lead the state, as they would lead it toward the path of happiness. Whilst knowledge of the Good is different from knowledge of science, rulers are here appointed based on a certain grasp of technical skill, rather than democratic mandate.

Characteristics.

Technocrats are individuals with technical training and occupations who perceive many important societal problems as being solvable with the applied use of technology and related applications. The administrative scientist Gunnar K. A. Njalsson theorizes that technocrats are primarily driven by their cognitive "problem-solution mindsets" and only in part by particular occupational group interests. Their activities and the increasing success of their ideas are thought to be a crucial factor behind the modern spread of technology and the largely ideological concept of the "information society". Technocrats may be distinguished from "econocrats" and "bureaucrats" whose problem-solution mindsets differ from those of the technocrats.

Examples.

In 2013, a European Union library briefing on its legislative structure referred to the Commission as a "technocratic authority", holding "legislative monopoly" over the EU lawmaking process. The briefing suggests that this system, which relegates the European Parliament to a vetoing and amending body, was "originally rooted in the mistrust of the political process in post-war Europe." This system is unusual, since the Commission's sole right of legislative initiative is a power usually associated with Parliaments, though the UK has an identical setup where only the appointed government can propose legislation.  The former government of the Soviet Union has been referred to as a technocracy. Soviet leaders like Leonid Brezhnev often had a technical background in education; in 1986, 89% of Politburo members were engineers.  Leaders of the Communist Party of China used to be mostly professional engineers. As a result of surveying the mayor and governor of a city with a population of 1 million or more in China, more than 80% often had a technical background in education. The Five-year plans of the People's Republic of China have enabled them to plan ahead in a technocratic fashion to build projects such as the National Trunk Highway System, the China high-speed rail system, and the Three Gorges Dam. However under Party general secretary Xi Jinping, engineers have been mostly replaced by political experts, economists and theorists; Xi himself is the only one to have an engineering degree in the current Politburo Standing Committee.  Several governments in European parliamentary democracies have been labeled 'technocratic' based on the participation of unelected experts ('technocrats') in prominent positions. Since the 1990s, Italy has had several such governments (in Italian, "governo tecnico") in times of economic or political crisis, including the formation in which economist Mario Monti presided over a cabinet of unelected professionals. The term 'technocratic' has been applied to governments where a cabinet of elected professional politicians is led by an unelected prime minister, such as in the cases of the 2011-2012 Greek government led by economist Lucas Papademos, and the Czech Republic's 2009–2010 caretaker government presided over by the state's chief statistician, Jan Fischer. In December 2013, in the framework of the national dialogue facilitated by Tunisian National Dialogue Quartet, political parties in Tunisia agreed to install a technocratic government led by Mehdi Jomaa.  In the article "Technocrats: Minds Like Machines", it is stated that Singapore is perhaps the best advertisement for technocracy: the political and expert components of the governing system there seem to have merged completely. This was underlined in a 1993 article in "Wired" by Sandy Sandfort, where he describes the information technology system of the island even at that early date making it effectively intelligent.

Engineering.

Following Samuel Haber, Donald Stabile argues that engineers were faced with a conflict between physical efficiency and cost efficiency in the new corporate capitalist enterprises of the late nineteenth century United States. The profit-conscious, non-technical managers of firms where the engineers work, because of their perceptions of market demand, often impose limits on the projects that engineers desire to undertake.  The prices of all inputs vary with market forces thereby upsetting the engineer's careful calculations. As a result, the engineer loses control over projects and must continually revise plans. To keep control over projects the engineer must attempt to exert control over these outside variables and transform them into constant factors.

Technocracy movement.

The American economist and sociologist Thorstein Veblen was an early advocate of technocracy, and was involved in the Technical Alliance as was Howard Scott and M. King Hubbert (who later developed the theory of peak oil). Veblen believed that technological developments would eventually lead toward a socialistic organization of economic affairs. Veblen saw socialism as one intermediate phase in an ongoing evolutionary process in society that would be brought about by the natural decay of the business enterprise system and by the inventiveness of engineers. Daniel Bell sees an affinity between Veblen and the Technocracy movement.  In 1932, Howard Scott and Marion King Hubbert founded Technocracy Incorporated, and proposed that money be replaced by energy certificates. The group argued that apolitical, rational engineers should be vested with authority to guide an economy into a thermodynamically balanced load of production and consumption, thereby doing away with unemployment and debt.  The technocracy movement was highly popular in the USA for a brief period in the early 1930s, during the Great Depression. By the mid-1930s, interest in the movement was declining. Some historians have attributed the decline of the technocracy movement to the rise of Roosevelt's New Deal.  Historian William E. Akin rejects the conclusion that technocracy ideas declined because of the attractiveness of Roosevelt and the New Deal. Instead Akin argues that the movement declined in the mid-1930s as a result of the technocrats' failure to devise a 'viable political theory for achieving change'. Akin postulates that many technocrats remained vocal and dissatisfied and often sympathetic to anti-New Deal third party efforts.

Critiques.

Critics have suggested that a "technocratic divide" exists between a governing body controlled to varying extents by technocrats, and members of the general public. Said another way, technocratic divides are "efficacy gaps that persist between governing bodies employing technocratic principles and members of the general public aiming to contribute to government decision making." The central challenge raised by these divides is that technocrats provide privilege and aristocracy to the opinions and viewpoints of technical experts, while marginalizing the opinions and viewpoints of the general public.  As multinational technology corporations (e.g., FAANG) inexorably swell market caps and customer counts, critiques of technocratic government in the 21st-century see its manifestation in American politics "not" as an "authoritarian nightmare of oppression and violence" "per se," but rather as an éminence grise: a "Wizard of Oz–"esque democratic cabal directed by Mark Zuckerberg and the entire cohort of "Big Tech" executives. In his 1982 Technology and Culture journal article, "The Technocratic Image and the Theory of Technocracy", John G. Gunnell presciently writes: "...politics is increasingly subject to the influence of technological change", with specific reference to the advent of The Long Boom and the genesis of the Internet, following the 1973-1975 Recession. Moreover, Gunnel presents three distinct levels of analysis to delineate technology's political influence: 1) "political power tends to gravitate towards technological elites"; 2) "technology has become autonomous" and thus impenetrable by political structures; and 3) "technology (and science) constitute a new legitimizing ideology", as well as triumphing over "tribalism, nationalism, the crusading spirit in religion, bigotry, censorship, racism, persecution, immigration and emigration restrictions, tariffs, and chauvinism". In each of the three analytical levels, Gunnell foretells of technology's infiltration of political processes, and suggests that the entanglement of the two (i.e. technology and politics) will inevitably produce power concentrations around those with advanced technological training, namely, the technocrats. Forty years after the publication of Gunnell's prophetic writings, technology and government have became, for better or worse, increasingly intertwined. Facebook in itself can be considered a technocratic microcosm, a "technocratic nation-state", with a cyberspatial population that eclipses that of any terrestrial nation. In a broader sense, critics fear that the rise of social media networks (e.g., Twitter, YouTube, Instragram, Pintrest), coupled with the "decline in mainstream engagement", imperil the ""networked young citizen"" to inconspicuous coercion and indoctrination by algorithmic mechanisms, and, more innocuously, to the persuasion of particular candidates based predominantly on "Social Media engagement".

Technocracy is an ideological system of governance in which decision-makers are selected on the basis of their expertise in a given area of responsibility, particularly with regard to scientific or technical knowledge. This system explicitly contrasts with the notion that elected representatives should be the primary decision-makers in government, though it does not necessarily imply eliminating elected representatives. Leadership skills for decision-makers are selected on the basis of specialized knowledge and performance, rather than political affiliations or parliamentary skills.

专家统治(Technocracy),又称技术官僚主义。在决策系统中,决策者是根据其在给定责任领域(尤其是在科学或技术知识方面)的专业知识来选拔的。该制度与民选代表应成为政府的主要决策者这一观念形成了鲜明的对比,尽管这不一定意味着要消除民选代表。决策者的领导才能是根据专业知识和表现来选择的,而不是根据政治背景或议会的技巧来选择的。


Conserved function of DNA methylation.

The DNA methylation landscape of vertebrates is very particular compared to other organisms. In mammals, around 75% of CpG dinucleotides are methylated in somatic cells, and DNA methylation appears as a default state that has to be specifically excluded from defined locations. By contrast, the genome of most plants, invertebrates, fungi, or protists show “mosaic” methylation patterns, where only specific genomic elements are targeted, and they are characterized by the alternation of methylated and unmethylated domains.  High CpG methylation in mammalian genomes has an evolutionary cost because it increases the frequency of spontaneous mutations. Loss of amino-groups occurs with a high frequency for cytosines, with different consequences depending on their methylation. Methylated C residues spontaneously deaminate to form T residues over time; hence CpG dinucleotides steadily deaminate to TpG dinucleotides, which is evidenced by the under-representation of CpG dinucleotides in the human genome (they occur at only 21% of the expected frequency). (On the other hand, spontaneous deamination of unmethylated C residues gives rise to U residues, a change that is quickly recognized and repaired by the cell.)

CpG islands.

In mammals, the only exception for this global CpG depletion resides in a specific category of GC- and CpG-rich sequences termed CpG islands that are generally unmethylated and therefore retained the expected CpG content. CpG islands are usually defined as regions with 1) a length greater than 200bp, 2) a G+C content greater than 50%, 3) a ratio of observed to expected CpG greater than 0.6, although other definitions are

Repression of CpG-dense promoters.

DNA methylation was probably present at some extent in very early eukaryote ancestors. In virtually every organism analyzed, methylation in promoter regions correlates negatively with gene expression. CpG-dense promoters of actively transcribed genes are never methylated, but, reciprocally, transcriptionally silent genes do not necessarily carry a methylated promoter. In mouse and human, around 60–70% of genes have a CpG island in their promoter region and most of these CpG islands remain unmethylated independently of the transcriptional activity of the gene, in both differentiated and undifferentiated cell types. Of note, whereas DNA methylation of CpG islands is

Repression of transposable elements.

DNA methylation is a powerful transcriptional repressor, at least in CpG dense contexts. Transcriptional repression of protein-coding genes appears essentially limited to very specific classes of genes that need to be silent permanently and in almost all tissues. While

Methylation of the gene body of highly transcribed genes.

A function that appears even more conserved than transposon silencing is positively correlated with gene expression. In almost all species where DNA methylation is present, DNA methylation is especially enriched in the body of highly transcribed genes. The function of gene body methylation is not well understood. A body of evidence suggests that it could regulate

In mammals.

During embryonic development.

DNA methylation patterns are largely erased and then re-established between generations in mammals. Almost all of the methylations from the parents are erased, first during gametogenesis, and again in early embryogenesis, with demethylation and remethylation occurring each time. Demethylation in early embryogenesis occurs in the preimplantation period in two stages – initially in the zygote, then during the first few embryonic replication cycles of morula and blastula. A wave of methylation then takes place during the implantation stage of the embryo, with CpG islands protected from methylation. This results in global repression and allows housekeeping genes to be expressed in all cells. In the post-implantation stage, methylation patterns are stage- and tissue-specific, with changes that would define each individual cell type lasting stably over a long period.  Whereas DNA methylation is not necessary "per se" for transcriptional silencing, it is thought nonetheless to represent a “locked” state that definitely inactivates transcription. In particular, DNA methylation appears critical

In cancer.

In many disease processes, such as cancer, gene promoter CpG islands acquire abnormal hypermethylation, which results in transcriptional silencing that can be inherited by daughter cells following cell division. Alterations of DNA methylation have been recognized as an important component of cancer development. Hypomethylation, in general, arises earlier and is linked to chromosomal instability and loss of imprinting, whereas hypermethylation is associated with promoters and can arise secondary to gene (oncogene suppressor) silencing, but might be a target for epigenetic therapy.  Global hypomethylation has also been implicated in the development and progression of cancer through different mechanisms. Typically,

In atherosclerosis.

Epigenetic modifications such as DNA methylation have been implicated in cardiovascular disease, including atherosclerosis. In animal models of atherosclerosis, vascular tissue, as well as blood cells such as mononuclear blood cells, exhibit global hypomethylation with gene-specific areas of hypermethylation. DNA methylation polymorphisms may be used as an early biomarker of atherosclerosis since they are present before lesions are observed, which may provide an early tool for detection and risk prevention.  Two of the cell types targeted for DNA methylation polymorphisms are monocytes and lymphocytes, which experience an overall hypomethylation. One proposed mechanism behind this global hypomethylation is elevated homocysteine levels causing hyperhomocysteinemia, a known risk factor for cardiovascular disease. High plasma levels of homocysteine inhibit DNA methyltransferases, which causes hypomethylation. Hypomethylation of DNA affects genes that alter smooth muscle cell proliferation, cause endothelial cell dysfunction, and increase inflammatory mediators, all of which are

In aging.

In humans and other mammals, DNA methylation levels can be used to accurately estimate the age of tissues and cell types, forming an accurate epigenetic clock.  A longitudinal study of twin children showed that, between the ages of 5 and 10, there was divergence of methylation patterns due to environmental rather than genetic influences. There is a

In exercise.

High intensity exercise has been shown to result in reduced DNA methylation in skeletal muscle. Promoter methylation of PGC-1α and PDK4 were immediately reduced after high intensity exercise, whereas PPAR-γ methylation was

In B-cell differentiation.

A study that investigated the methylome of B cells along their differentiation cycle, using whole-genome bisulfite sequencing (WGBS), showed that there is a hypomethylation from the earliest stages to

In the brain.

Two reviews summarize evidence that DNA methylation alterations in brain neurons are important in learning and memory. Contextual fear conditioning (a form of associative learning) in animals, such as mice and rats, is rapid and is extremely robust in creating memories. In mice and in rats contextual fear conditioning, within 1–24 hours, it is associated with altered methylations of several thousand DNA cytosines in genes of hippocampus neurons. Twenty four hours after

DNA methyltransferases (in mammals).

In mammalian cells, DNA methylation occurs mainly at the C5 position of CpG dinucleotides and is carried out by two general classes of enzymatic activities – maintenance methylation and "de novo" methylation.  Maintenance methylation activity is necessary to preserve DNA methylation after every cellular DNA replication cycle. Without the DNA methyltransferase (DNMT), the replication machinery itself would produce daughter strands that are unmethylated and, over time, would lead to passive demethylation. DNMT1 is the proposed maintenance methyltransferase that is responsible for copying DNA methylation patterns to the daughter strands during DNA replication. Mouse models with both copies of DNMT1 deleted are embryonic lethal at approximately day 9, due to the requirement of DNMT1 activity for development in mammalian cells.  It is thought that DNMT3a and DNMT3b are the "de novo" methyltransferases that set up DNA methylation patterns early in development. DNMT3L is a protein that is homologous to the other DNMT3s but has no catalytic activity. Instead, DNMT3L assists the "de novo" methyltransferases by increasing their ability to bind to DNA and stimulating their activity. Mice and rats

In plants.

Significant progress has been made in understanding DNA methylation in the model plant "Arabidopsis thaliana". DNA methylation in plants differs from that of mammals: while DNA methylation in mammals mainly occurs on the cytosine nucleotide in a CpG site, in plants the cytosine can be methylated at CpG, CpHpG, and CpHpH sites, where H represents any nucleotide but not guanine. Overall, "Arabidopsis" DNA is highly methylated, mass spectrometry analysis estimated 14% of cytosines to be modified.  The principal "Arabidopsis" DNA methyltransferase enzymes, which transfer and covalently attach methyl groups onto DNA, are DRM2, MET1, and CMT3. Both the DRM2 and MET1 proteins share significant homology to the mammalian methyltransferases DNMT3 and DNMT1, respectively, whereas the CMT3 protein is unique to the plant kingdom. There are currently two classes of DNA methyltransferases: 1) the "de novo" class or enzymes that create new methylation marks on the DNA; 2) a maintenance class that recognizes the methylation marks on the parental strand of DNA and transfers new

In insects.

Diverse orders of insects show varied patterns of DNA methylation, from almost undetectable levels in flies to low levels in butterflies and higher in true bugs and some cockroaches (up to 14% of all CG sites in "Blattella asahinai").  Functional DNA methylation has been discovered in Honey Bees. DNA methylation marks are mainly on the gene body, and current opinions on the function of DNA methylation is gene regulation via alternative splicing  "DNA

In fungi.

Many fungi have low levels (0.1 to 0.5%) of cytosine methylation, whereas other fungi have as much as 5% of the genome methylated. This value seems to vary both among species and among isolates of the same species. There is also evidence that DNA methylation may be involved in state-specific control of gene expression in fungi. However, at a detection limit of 250 attomoles by using ultra-high sensitive mass spectrometry DNA methylation was not confirmed in single cellular

In other eukaryotes.

DNA methylation is largely absent from Dictyostelium discoidium where it appears to occur at about 0.006%

In bacteria.

Adenine or cytosine methylation is part of the restriction modification system of many bacteria, in which specific DNA sequences are methylated periodically throughout the genome. A methylase is the enzyme that recognizes a specific sequence and methylates one of the bases in or near that sequence. Foreign DNAs (which are not methylated in this manner) that are introduced into the cell are degraded by sequence-specific restriction enzymes and cleaved. Bacterial genomic DNA is not recognized by these restriction enzymes. The methylation of native DNA acts as a sort of primitive immune system, allowing the bacteria to protect themselves from infection by bacteriophage.  "E. coli" DNA adenine methyltransferase (Dam) is an enzyme of ~32 kDa that does not belong to a restriction/modification system. The target recognition sequence for "E. coli" Dam is GATC, as the methylation occurs at the N6 position of the adenine in this sequence (G meATC). The three base pairs flanking each side of this site also influence DNA–Dam binding. Dam plays several key roles in bacterial processes, including mismatch repair, the timing of DNA replication, and gene expression. As a result of DNA replication, the status of GATC sites in the "E. coli" genome changes from fully methylated to hemimethylated. This is because adenine introduced into the new DNA strand is unmethylated. Re-methylation occurs within two to four seconds, during which time replication errors in the new strand are repaired. Methylation, or its absence, is the marker that allows the repair apparatus of the cell to differentiate between the template and nascent strands. It has been shown that altering Dam activity in bacteria results in an increased spontaneous mutation rate. Bacterial viability is compromised in dam mutants that also lack certain other DNA repair enzymes, providing further evidence for the role of Dam in DNA repair.  One region of the DNA that keeps its hemimethylated status for longer is the origin of replication, which has an abundance of GATC sites. This is central to the bacterial mechanism for timing DNA replication. SeqA binds to the origin of replication, sequestering it and thus preventing methylation. Because hemimethylated origins of replication are inactive, this mechanism limits DNA replication to once per cell cycle.  Expression of certain genes, for example, those coding for pilus expression in "E. coli", is regulated by the methylation of GATC sites in the promoter region of the gene operon. The cells' environmental conditions just after DNA replication determine whether Dam is blocked from methylating a region proximal to or distal from the promoter region. Once the pattern of methylation has been created, the pilus gene transcription is locked in the on or off position until the DNA is again replicated. In "E. coli", these pili operons have important roles in virulence in urinary tract infections. It has been proposed that inhibitors of Dam may function as antibiotics.  On the other hand, DNA cytosine methylase targets CCAGG and CCTGG sites to methylate cytosine at the C5 position (C meC(A/T) GG). The other methylase enzyme, EcoKI, causes methylation of adenines in the sequences AAC(N)GTGC and GCAC(N)GTT.  In "Clostridioides difficile", DNA methylation at the target motif CAAAAA was shown to impact sporulation, a key step in disease transmission, as well as cell length, biofilm formation and host colonization.

Detection.

DNA methylation can be detected by

Differentially methylated regions (DMRs).

Differentially methylated regions, are genomic regions with different methylation statuses among multiple samples (tissues, cells, individuals or others), are regarded as possible functional regions involved in gene transcriptional regulation. The identification of DMRs among multiple tissues (T-DMRs) provides a comprehensive survey of epigenetic differences among human tissues. For example, these methylated regions that are unique to a particular tissue allow individuals to differentiate between tissue type, such as semen and vaginal fluid. Current research conducted by Lee et al., showed DACT1 and USP49 positively identified semen by examining T-DMRs. The use of T-DMRs has proven useful in the identification of various body fluids found at crime scenes. Researchers in the forensic field are currently seeking novel T-DMRs in genes to use as markers in forensic DNA analysis. DMRs between cancer and normal samples (C-DMRs) demonstrate the aberrant methylation in cancers. It is well known that DNA methylation is associated

DNA methylation marks.

DNA methylation marks – genomic regions with specific methylation patterns in a specific biological state such as tissue, cell type, individual – are regarded as possible functional regions involved in gene transcriptional regulation. Although various human cell types may have the same genome, these cells have different methylomes. The systematic identification and characterization of methylation marks across cell types are crucial to understanding the complex regulatory network for cell fate determination. Hongbo Liu et al. proposed an entropy-based framework termed SMART to integrate the whole genome bisulfite sequencing methylomes across 42 human tissues/cells and identified 757,887 genome segments. Nearly 75% of the segments showed uniform methylation across all cell types. From the remaining 25% of the segments, they identified cell type-specific hypo/hypermethylation marks that were specifically hypo/hypermethylated in a minority of cell types using a statistical approach and presented an atlas of the human methylation marks. Further analysis revealed that the cell type-specific hypomethylation marks were enriched through H3K27ac and transcription factor binding sites in a cell type-specific manner. In particular, they observed that the cell type-specific hypomethylation marks are associated with the cell type-specific super-enhancers that drive the expression of cell identity genes. This framework provides a complementary, functional annotation of the human genome and helps to elucidate the critical features and functions of cell type-specific hypomethylation.  The entropy-based Specific Methylation Analysis and Report Tool, termed "SMART", which focuses on integrating a large number of DNA methylomes for the de novo identification of cell type-specific methylation marks. The latest version of SMART is focused on three main functions including de novo identification of differentially methylated regions (DMRs) by genome segmentation, identification of DMRs from predefined regions of interest, and identification of differentially methylated CpG sites.

In identification and detection of body fluids.

DNA methylation allows for several tissues to be analyzed in one assay as well as for small amounts of body fluid to be identified with the use of extracted DNA. Usually, the two approaches of DNA methylation are either methylated-sensitive restriction enzymes or treatment with sodium bisulphite. Methylated sensitive restriction enzymes work by cleaving specific CpG, cytosine and guanine separated by only one phosphate group, recognition sites when the CpG is methylated. In contrast, unmethylated cytosines are transformed to uracil and in the process, methylated cytosines remain methylated. In particular, methylation profiles can provide insight on when or how body fluids were left at crime scenes, identify the kind of body fluid, and approximate age, gender, and phenotypic characteristics of perpetrators. Research indicates various markers that can be used for DNA methylation. Deciding which marker to use for an assay is one of the first steps of the identification of body fluids. In general, markers are selected by examining prior research conducted. Identification markers that are chosen

Computational prediction.

DNA methylation can also be detected by computational models through sophisticated algorithms and methods. Computational models can facilitate the global profiling of DNA methylation across chromosomes, and often such models are faster and cheaper to perform than biological assays. Such up-to-date computational models include Bhasin, "et al.", Bock, "et al"., and Zheng, "et al".<ref name="10.1186/1755-8794-6-S1-S13"></ref> Together with biological assay, these methods greatly facilitate the DNA methylation analysis.

DNA methylation is a biological process by which methyl groups are added to the DNA molecule. Methylation can change the activity of a DNA segment without changing the sequence. When located in a gene promoter, DNA methylation typically acts to repress gene transcription. In mammals, DNA methylation is essential for normal development and is associated with a number of key processes including genomic imprinting, X-chromosome inactivation, repression of transposable elements, aging, and carcinogenesis.

DNA甲基化(英语:DNA methylation)为DNA化学修饰的一种形式,能在不改变DNA序列的前提下,改变遗传表现。为表观遗传编码(epigenetic code)的一部分,是一种外遗传机制。DNA甲基化过程会使甲基添加到DNA分子上,例如在胞嘧啶环的5'碳上:这种5'方向的DNA甲基化方式可见于所有脊椎动物。


本·约翰逊 (田径运动员)

Biography.

Career background.

Benjamin Johnson was born in Falmouth, Jamaica, and immigrated to Canada in 1976, residing in Scarborough, Ontario.  Johnson met coach Charlie Francis and joined the Scarborough Optimists track and field club, training at York University. Francis was a Canadian 100 metres sprint champion himself (1970, 1971 and 1973) and a member of the Canadian team for the 1972 Summer Olympics in Munich. Francis was also Canada's national sprint coach for nine years.  Johnson's first international success came when he won 2 silver medals at the 1982 Commonwealth Games in Brisbane, Australia. He finished behind Allan Wells of Scotland in the 100 metres with a time of 10.05 seconds and was a member of the Canadian 4 × 100 metres relay team which finished behind Nigeria. This success was not repeated at the 1983 World Championships in Helsinki, where he was eliminated in the semi-finals, finishing 6th with a time of 10.44, nor at the 1983 Pan American Games in Caracas where Johnson placed 5th in the 100 metres final with a time of 10.25.  At the 1984 Summer Olympics in Los Angeles, he reached the 100 metres final; after a false start, he won the bronze medal behind Carl Lewis and Sam Graddy with a time of 10.22. He also won a bronze medal with the Canadian 4 × 100 m relay team of Johnson, Tony Sharpe, Desai Williams and Sterling Hinds, who ran a time of 38.70. By the end of the 1984 season, Johnson had established himself as Canada's top sprinter, and on August 22 in Zürich, Switzerland, he bettered Williams' Canadian record of 10.17 by running 10.12.  In 1985, after eight consecutive losses, Johnson finally beat Carl Lewis. Other success against Lewis included the 1986 Goodwill Games, where Johnson beat Lewis, running 9.95 for first place, against Lewis' third-place time of 10.06. He broke Houston McTear's seven-year-old world record in the 60 metres in 1986, with a time of 6.50 seconds. He also won Commonwealth gold at the 1986 games in Edinburgh, beating Linford Christie for the 100 metres title with a time of 10.07. Johnson also led the Canadian 4x100 metres relay team to gold, and won a bronze in the 200 metres. Also in 1986, Canadian sprinter Mike Dwyer expressed concern that the use of drugs had reached "epidemic proportions" among Canadian sprinters, particularly among those who trained in the Toronto area. Atlee Mahorn also speculated that many sprinters were on steroids.  On April 29, 1987, Johnson was invested as a Member of the Order of Canada. "World record holder for the indoor 60-meter run, this Ontarian has proved himself to be the world's fastest human being and has broken Canadian, Commonwealth and World Cup 100-meter records," it read. "Recipient of the Norton Crowe Award for Male Athlete of the Year for 1985, 'Big Ben' was the winner of the 1986 Lou Marsh Trophy as Canada's top athlete."  By the time of the 1987 World Championships, Johnson had won his four previous races with Lewis and had established himself as the best 100 metres sprinter. At Rome, Johnson gained instant world fame and confirmed this status when he beat Lewis for the title, setting a new world record of 9.83 seconds as well, beating Calvin Smith's former record by a full tenth of a second.  After Rome, Johnson became a lucrative marketing celebrity. According to coach Charlie Francis, after breaking the world record, Johnson earned about $480,000 a month in endorsements. Johnson won both the Lou Marsh Trophy and Lionel Conacher Award, and was named the Associated Press Athlete of the Year for 1987.  Following Johnson's defeat of Lewis in Rome, Lewis started trying to explain away his defeat. He first claimed that Johnson had false-started, then he alluded to a stomach virus which had weakened him. Finally, without naming names, Lewis said "There are a lot of people coming out of nowhere. I don't think they are doing it without drugs." This was the start of Lewis' calling on the sport of track and field to be cleaned up in terms of the illegal use of performance-enhancing drugs. While cynics noted that the problem had been in the sport for many years, they pointed out that it did not become a cause for Lewis until he was actually defeated, with some also pointing to Lewis's egotistical attitude and lack of humility. During a controversial interview with the BBC, Lewis said: There are gold medallists at this meet who are on drugs, that [100 metres] race will be looked at for many years, for more reasons than one. Johnson's response was: When Carl Lewis was winning everything, I never said a word against him. And when the next guy comes along and beats me, I won't complain about that either. This set up the rivalry leading into the 1988 Olympic Games.  In 1988, Johnson experienced a number of setbacks to his running career. In February of that year he pulled a hamstring, and in May he aggravated the same injury. Meanwhile, in Paris in June, Lewis ran a 9.99. Then in Zurich, Switzerland on August 17, the two faced each other for the first time since the 1987 World Championships; Lewis won in 9.93, while Johnson finished third in 10.00. "The gold medal for the (Olympic) 100 meters is mine," Carl Lewis said. "I will never again lose to Johnson."

Olympic games and subsequent disqualification.

On September 24, 1988, Johnson was thought to be the first sprinter from Canada since Percy Williams in 1928 to win the 100 metres final at the Summer Olympics in Seoul, lowering his own world record to 9.79 seconds. Johnson would later remark that he would have been even faster had he not raised his hand in the air just before he hit the tape. However, Park Jong-sei of the Olympic Doping Control Center found that Johnson's urine sample contained stanozolol, and he was disqualified three days later. He later admitted having used steroids when he ran his 1987 world record, which caused the IAAF to rescind that record as well. Johnson and coach Francis complained that they used performance-enhancing agents in order to remain on equal footing with the other top athletes. In testimony before the Dubin Inquiry into drug use in sport, Francis charged that Johnson was only one of many cheaters, and he just happened to get caught. Later, six of the eight finalists of the 100 metres race tested positive for banned drugs or were implicated in a drug scandal at some point in their careers: Carl Lewis, who was given the gold medal; Linford Christie, who was moved up to the silver medal and went on to win gold at the next Games; Dennis Mitchell, who was moved up to fourth place and finished third to Christie in 1992; and Desai Williams, Johnson's countryman who won a bronze medal in the 4 × 100 metres relay at the Los Angeles Games in 1984.  Johnson's coach, Charlie Francis, a vocal critic of the IOC testing procedures, is the author of "Speed Trap", which features Johnson heavily. In the book, he freely admits that his athletes were taking anabolic steroids, as he claims all top athletes at the time were, and also claims that Johnson could not possibly have tested positive for that particular steroid since Johnson actually preferred furazabol. He thought stanozolol made his body "feel tight". The numerous athletes using performance-enhancing drugs at the time understood how long before a race, and possible drug test, they should stop using the drugs. Johnson later claimed that André A. Jackson, Lewis' Santa Monica Track Club teammate, who was inside the drug testing room in Seoul, may have placed the stanozolol in one of the beers Johnson drank in order to make urine for his test.  On 28 September 2018, the Toronto Star ran an article on the lab report which was created on Johnson's sample during the 1988 Olympic Games. It was produced by the IOC Doping Control Center in Seoul two days after Johnson handed in a urine sample taken after the 100m final. The newspaper concluded that the assumed substance Stanozolol was traceable, but "inconsistencies" are found in the report. The Toronto Star article goes on state that no Canadian Olympic team official saw the lab report in Seoul. The lab report was requested by Canada's chief medical officer, Dr. William Stanish. The Canadian team didn't object after the IOC Medical Commission assured "that its testing methods were unassailable."

The Canadian reaction.

Canadians rejoiced in the reflected glory of winning the gold medal and breaking the world record.  Canadian Prime Minister Brian Mulroney watched Johnson set the new world record and after the race congratulated him over the phone. "It's a marvellous evening for Canada," Mulroney said in the televised conversation.  Newspapers covered the occasion by concocting words such as "Benfastic" ("Toronto Star", September 25, 1988) to describe it. Two days later, Canadians witnessed the downfall of Johnson, when he was stripped of his gold medal and world record. Mark Tewksbury, a Canadian Olympic swimmer hung a bed sheet banner out of his Olympic Village apartment window expressing 'Hero to Zero in 9.79'. In the first week following the dethroning, Canadian newspapers devoted between five and eight pages a day to the story. Some squarely placed the blame on Johnson, such as one headline right after the exposure suggests: "Why, Ben?" ("Toronto Sun", September 26, 1988). Because of the Olympic scandal, the Canadian news agency "Canadian Press" named Johnson "Newsmaker of the Year" for 1988.

The Dubin Inquiry.

After the Seoul test, he initially denied doping, but, testifying before the 1989 Dubin Inquiry, a Canadian government investigation into drug abuse, Johnson admitted that he had lied. Charlie Francis, his coach, told the inquiry that Johnson had been using steroids since 1981.  In Canada, the federal government established the Commission of Inquiry Into the Use of Drugs and Banned Practices Intended to Increase Athletic Performance, headed by Ontario Appeal Court Chief Justice Charles Dubin. The Dubin Inquiry (as it became known), which was televised live, heard hundreds of hours of testimony about the widespread use of performance-enhancing drugs among athletes. The inquiry began in January 1989 and lasted 91 days, with 122 witnesses called, including athletes, coaches, sport administrators, IOC representatives, doctors and government officials.

Comeback.

In 1991, after his suspension ended, he attempted a comeback. He returned to the track for the Hamilton Indoor Games in 1991 and was greeted by the largest crowd to ever attend an indoor Canadian track and field event. More than 17,000 people saw him finish second in the 50 metres in 5.77 seconds.  He failed to qualify for the 1991 World Championships in Tokyo but made the Canadian Olympic team again in 1992 in Barcelona, Spain after finishing second at the Canadian Olympic trials to Bruny Surin. He missed the 100 metre finals at the Olympics, however, finishing last in his semi-final heat after stumbling out of the blocks.  In 1993, he won the 50 metres on January 7 in Grenoble, France, in 5.65 seconds, just 0.04 seconds shy of the world record. However, he was again found guilty of doping just after the race – this time for excess testosterone – and was subsequently banned for life by the IAAF. Federal amateur sport minister Pierre Cadieux called Johnson a national disgrace, and suggested he consider moving back to Jamaica. Johnson commented that it was "by far the most disgusting comment [he had] ever heard". In April 1999, a Canadian adjudicator ruled that there were procedural errors in Johnson's lifetime ban and allowed him to appeal. The decision meant Johnson could technically run in Canada but nobody would compete against him. They would be considered "contaminated" by the IAAF and could also face sanctions. On June 12, 1999, Johnson entered a track meet in Kitchener, Ontario, and was forced to run alone, against the clock. He posted a time of 11.0 seconds. In late 1999, Johnson failed a drug test for the third time by testing positive for hydrochlorothiazide, a banned diuretic that can be used to mask the presence of other drugs. Johnson had not competed since 1993 and had arranged the test himself as part of his efforts to be reinstated.  In 1999, Johnson made headlines again when it was revealed that he had been hired by Libyan leader Muammar Gaddafi to act as a football coach for his son, Al-Saadi Gaddafi, who aspired to join an Italian football club. Al-Saadi ultimately did join an Italian team but was sacked after one game when he failed a drug test. Johnson's publicist in Canada had predicted in "The Globe and Mail" that his training of the young Gaddafi would earn Johnson a Nobel Peace Prize.

Late 1990s and beyond.

Johnson briefly acted as trainer for Argentine football player Diego Maradona in 1997. This occurred at York University, Toronto.  In 1998, Johnson appeared in a charity race in Charlottetown, Prince Edward Island, where he raced against a thoroughbred race horse, a harness racing horse and a stock car. Johnson finished third in the race.  According to a 1998 article in "Outside" magazine, Johnson spent much of the latter part of the 1990s living downstairs in the house he shared with his mother Gloria. He spent his leisure time reading, watching movies, and taking his mother to church. He lived in a spacious home in Newmarket, Ontario's Stonehaven neighborhood. He claims to have lost his Ferrari when he used it as collateral for a loan from an acquaintance in order to make a house payment. His mother died of cancer in 2004 and Johnson lived with his sister afterwards.  Shortly after his leaving Libya, it was reported that Johnson had been robbed of $7,300 by a Romani gang in Rome. His wallet was taken, containing $7,300 in cash, the proceeds of his pay for training Gaddafi. Johnson gave chase, but was unable to catch them after they vanished into a subway station.  In May 2005, Johnson launched a clothing and sports supplement line, the "Ben Johnson Collection". The motto for Johnson's clothing line was "Catch Me"; however, the clothing line never caught on.  In a January 1, 2006 interview, Johnson claimed that he was sabotaged by a "Mystery Man" inside the doping-control room immediately following the 100 metres final in Seoul. He also stated that 40% of people in the sports world are still taking drugs to improve their performance.  In August 2008, Johnson filed a $37 million lawsuit against the estate of his former lawyer Ed Futerman, claiming Futerman made unauthorized payments from his trust account to pay bills and 20 percent commissions to a hairdresser recruited by the lawyer to act as the sprinter's sports agent. In 2012, the lawsuit was dismissed by the Ontario Superior Court by summary judgment on the basis that "there were no genuine issues raised requiring a trial".  At present, Johnson lives in Markham, Ontario and spends much of his time with his daughter and granddaughter. He also continues to coach, notably with New Jersey Devils defenseman P.K. Subban. In 2010, he released his autobiography entitled "Seoul to Soul." In the self-published book, Johnson reviews his childhood in Jamaica, and his early bout with malaria. A Canadian Press article described the book as "an unconventional sports autobiography."

Acting career.

In March 2006, television spots featuring Johnson advertising an energy drink, "Cheetah Power Surge", started to receive some airtime. Some pundits questioned whether Johnson was an appropriate spokesperson for an all natural energy drink considering his history of steroid use. One ad is a mock interview between Johnson and Frank D'Angelo, the president and chief executive of D'Angelo Brands, which makes the drink, in which he asks Johnson: "Ben, when you run, do you Cheetah?" "Absolutely," says Johnson. "I Cheetah all the time." The other commercial includes Johnson and a cheetah, the world's fastest land animal, and encourages viewers to "go ahead and Cheetah."  In May 2017, Ben appeared in an advertising campaign for Australia's leading mobile bookmaker, Sportsbet. The campaign launches Sportsbet's new Android app, and Ben cheekily says it "has tested positive for speed and power, again and again". The campaign tagline is "Putting the 'Roid in Android" and concludes with Ben in the starters block on a racing track, telling punters to "get on it!" The ad can be found on YouTube.

Documentaries.

The CBC radio documentary series "Rewind" broadcast an episode titled "Ben Johnson: A Hero Disgraced" on September 19, 2013, for the 25th anniversary of the race, revealing 20 athletes tested positive for drugs but were cleared by the IOC at the 1988 Seoul Olympics. An International Olympic Committee (IOC) official told the CBC that endocrine profiles done at those games indicated that 80 percent of the track and field athletes tested showed evidence of long-term steroid use, although few were banned or had their medals stripped.

Benjamin Sinclair Johnson, (born December 30, 1961) is a Jamaican-born Canadian former sprinter, who won two bronze medals at the 1984 Summer Olympics. He was stripped of his gold medals in the 100 metres at the 1987 World Championships and 1988 Summer Olympics after being disqualified for doping.

本杰明·辛克莱尔·强生(英语:Benjamin Sinclair Johnson,1961年-12月30日),出生于牙买加,前加拿大短跑运动员。


Distinguishing characteristics.

Jumping spiders are among the easiest to distinguish from similar spider families because of the shape of the cephalothorax and their eye patterns. The families closest to Salticidae in general appearance are the Corinnidae (distinguished also by prominent spines on the back four legs), the Oxyopidae (the lynx spiders, distinguished by very prominent spines on all legs), and the Thomisidae (the crab spiders, distinguished by their front four legs, which are very long and powerful). None of these families however, have eyes that resemble those of the Salticidae. Conversely, the legs of jumping spiders are not covered with any very prominent spines. Their front four legs generally are larger than the hind four, but not as dramatically so as those of the crab spiders, nor are they held in the outstretched-arms attitude characteristic of the Thomisidae. In spite of the length of their front legs, Salticidae depend on their rear legs for jumping. The generally larger front legs are used partly to assist in grasping prey, and in some species, the front legs and pedipalps are used in species-recognition signalling.  The jumping spiders, unlike the other families, have faces that are roughly rectangular surfaces perpendicular to their direction of motion. In effect this means that their forward-looking, anterior eyes are on "flat faces", as shown in the photographs. Their eye pattern is the clearest single identifying characteristic. They have eight eyes, as illustrated. Most diagnostic are the front row of four eyes, in which the anterior median pair are more dramatically prominent than any other spider eyes apart from the posterior median eyes of the Deinopidae. There is, however, a radical functional difference between the major (AME) eyes of Salticidae and the major (PME) eyes of the Deinopidae; the large posterior eyes of Deinopidae are adapted mainly to vision in dim light, whereas the large anterior eyes of Salticidae are adapted to detailed, three-dimensional vision for purposes of estimating the range, direction, and nature of potential prey, permitting the spider to direct its attacking leaps with great precision. The anterior lateral eyes, though large, are smaller than the AME and provide a wider forward field of vision.  The rear row of four eyes may be described as strongly bent, or as being rearranged into two rows, with two large posterior lateral eyes being the furthest back. They serve for lateral vision. The posterior median eyes also have been shifted out laterally, almost as far as the posterior lateral eyes. They are usually much smaller than the posterior lateral eyes and there is doubt about whether they are at all functional in many species.  The body length of jumping spiders generally ranges from. The largest is "Hyllus giganteus", while other genera with relatively large species include "Phidippus", "Philaeus" and "Plexippus".  In addition to using their silk for safety lines while jumping, they also build silken "pup tents", where they take shelter from bad weather and sleep at night. They molt in these shelters, build and store egg cases in them, and also spend the winter in them.

Habitat.

Jumping spiders live in a variety of habitats. Tropical forests harbor the most species, but they are also found in temperate forests, scrubland, deserts, intertidal zones, and mountainous regions. "Euophrys omnisuperstes" is the species reported to have been collected at the highest elevation, on the slopes of Mount Everest.

Vision.

Jumping spiders have four pairs of eyes; three secondary pairs that are fixed and a principal pair that is movable.  The posterior median eyes (PME) are vestigial in many species, but in some primitive subfamilies they are comparable in size with the other secondary eyes and help to detect motion. While unable to form images, it is suspected that the reduced pair of eyes has a role similar to that of insect ocelli by receiving light from the sky. The photoreceptors in the other secondary pairs are almost exclusively green-sensitive, but the PME have two visual pigments different from that in all the other eyes, sensitive to blue and UV-light.  The posterior lateral eyes (PLE) are wide-angle motion detectors which sense motions from the side and behind. Combined with the other eyes, it gives the spider a near 360-degree view of the world.  The anterior lateral eyes (ALE) have the best visual acuity of the secondary eyes. It has been shown that they are able to distinguish some details as well, and without them no "looming response" will be triggered by motion. Even with all the other pairs covered, jumping spiders in a study could still detect, stalk and attack flies, using the anterior lateral eyes only, which are also sufficiently widely spaced to provide stereoscopic vision.  The anterior median eyes (AME) have very good vision. This pair of eyes is built like a telescopic tube with a corneal lens in the front and a second lens in the back that focus images onto a four-layered retina, a narrow boomerang-shaped strip oriented vertically. Physiological experiments have shown they may have up to four different kinds of receptor cells, with different absorption spectra, giving them the possibility of tetrachromatic color vision, with sensitivity extending into the ultraviolet range. As the eyes are too close together to allow depth perception, and the animals do not make use of motion parallax, they have evolved a method called image defocus instead. Of the four photoreceptor layers in the retina, the first two closest to the surface contain ultraviolet-sensitive pigments while the two deepest contain green-sensitive pigments. The incoming green light is only focused on the deepest layer, while the other one receives defocused or fuzzy images. By measuring the amount of defocus from the fuzzy layer, it is possible to calculate the distance to the objects in front of them. In addition to receptor cells, also red filters have been detected, located in front of the cells that normally register green light. It seems that all salticids, regardless of whether they have two, three, or four kinds of color receptors, are highly sensitive to UV light. Some species (for example, "Cosmophasis umbratica") are highly dimorphic in the UV spectrum, suggesting a role in sexual signaling (Lim & Li, 2005). Color discrimination has been demonstrated in behavioral experiments.  The principal, anterior median eyes have high resolution (11 min visual angle), but the field of vision is narrow, from 2 to 5°. The central region of the retina, where acuity is highest, is no more than six or seven receptor rows wide. However, the eye can scan objects off the direct axis of vision. As the lens is attached to the carapace, the eye's scanning movements are restricted to its retina through a complicated pattern of translations and rotations. This dynamic adjustment is a means of compensation for the narrowness of the static field of vision. It is analogous to the way most primates move their eyes to focus images of interest onto the "fovea centralis". Such movements within the jumping spider's eyes are visible from outside when the attention of the spider is directed to various targets.

Behavior.

Jumping spiders are generally diurnal, active hunters. Their well-developed internal hydraulic system extends their limbs by altering the pressure of their body fluid (hemolymph) within them. This enables the spiders to jump without having large muscular legs like a grasshopper. Most jumping spiders can jump several times the length of their bodies. When a jumping spider is moving from place to place, and especially just before it jumps, it tethers a filament of silk (or 'dragline') to whatever it is standing on to protect itself if the jump should fail. Should it fall, for example if the prey shakes it off, it climbs back up the silk tether. Some species, such as "Portia", will actually let themselves down to attack prey such as a web spider apparently secure in the middle of its web. Like many other spiders that leave practically continuous silk trails, jumping spiders impregnate the silk line with pheromones that play a role in social and reproductive communication, and possibly in navigation.  Certain species of jumping spiders have been shown by experiment to be capable of learning, recognizing, and remembering colors, and adapting their hunting behavior accordingly.

Hunting.

The hunting behaviour of the Salticidae is confusingly varied compared to that of most spiders in other families. Salticids hunt diurnally as a rule, which is consistent with their highly developed visual system. When it detects potential prey, a jumping spider typically begins orienting itself by swivelling its cephalothorax to bring the anterior median eyes to bear. It then moves its abdomen into line with its cephalothorax. After that, it might spend some time inspecting the object of its attention and determining whether a camouflaged or doubtful item of prey is promising, before it starts to stalk slowly forward. When close enough, the spider pauses to attach a dragline, then springs onto the prey.  There are, though, many variations on the theme and many surprising aspects. For one thing, salticids do not necessarily follow a straight path in approaching prey. They may follow a circuitous course, sometimes even a course that takes the hunter through regions from which the prey is not visible. Such complex adaptive behaviour is hard to reconcile with an organism that has such a tiny brain, but some jumping spiders, in particular some species of "Portia", can negotiate long detours from one bush down to the ground, then up the stem of another bush to capture a prey item on a particular leaf. Such behaviour still is the subject of research.  Some salticid species are continually on the move, stopping periodically to look around for prey, which they then stalk immediately. Others spend more time scanning their surroundings from one position, actively stalking any prey they detect. Members of the genus "Phaeacius" take that strategy to extremes; they sit on a tree trunk, facing downwards and rarely do any stalking, but simply lunge down on any prey items that pass close before them.  Some Salticidae specialise in particular classes of prey. Ants comprise one such class. Most spiders, including most salticids, avoid worker ants, but several species not only eat them as a primary item in their diets, but also employ specialised attack techniques — "Corythalia canosa" for example, circles around to the front of the ant and grabs it over the back of its head. Such myrmecophagous species, however, will not necessarily refuse other prey items, and will routinely catch flies and similar prey in the usual salticid fashion, without the special precautions they apply in hunting dangerous prey such as ants. Ants offer the advantages of being plentiful prey items for which there is little competition from other predators, but it remains profitable to catch less hazardous prey when it presents itself.  Some of the most surprising hunting behaviour occurs among the araneophagous Salticidae, and it varies greatly in method. Many of the spider-hunting species quite commonly will attack other spiders, whether fellow salticids or not, in the same way as any other prey, but some kinds resort to web invasion; nonspecialists such as "Phidippus audax" sometimes attack prey ensnared in webs, basically in acts of kleptoparasitism — sometimes they leap onto and eat the web occupant itself, or simply walk over the web for that purpose.  Salticidae in the genera "Brettus", "Cyrba", "Gelotia", and "Portia" display more advanced web-invasion behavior. They slowly advance onto the web and vibrate the silk with their pedipalps and legs. In this respect, their behaviour resembles that of the Mimetidae, probably the most specialised of the araneophagous spider families. If the web occupant approaches in the manner appropriate to dealing with ensnared prey, the predator attacks.  The foregoing examples present the Salticidae as textbook examples of active hunters; they would hardly seem likely to build webs other than those used in reproductive activities, and in fact, most species really do not build webs to catch prey. However, exceptions occur, though even those that do build capture webs generally also go hunting like other salticids. Some "Portia" species, for example, spin capture webs that are functional, though not as impressive as some orb webs of the Araneidae; "Portia" webs are of an unusual funnel shape and apparently adapted to the capture of other spiders. "Spartaeus" species, on the other hand, largely capture moths in their webs. In their review of the ethology of Salticidae, Richman and Jackson speculate on whether such web building is a relic of the evolution of this family from web-building ancestors.  In hunting, Salticidae also use their silk as a tether to enable them to reach prey that otherwise would be inaccessible. For example, by advancing towards the prey to less than the jumping distance, then retreating and leaping in an arc at the end of the tether line, many species can leap onto prey on vertical or even on inverted surfaces, which of course in a gravitational field would not be possible without such a tether.  Having made contact with the prey, hunting Salticidae administer a bite to inject rapidly acting venom that gives the victim little time to react. In this respect, they resemble the Mimetidae and Thomisidae, families that ambush prey that often are larger than the predator, and they do so without securing the victim with silk; they accordingly must immobilise it immediately and their venom is adapted accordingly.

Diet.

Although jumping spiders are generally carnivorous, many species have been known to include nectar in their diets, and one species, "Bagheera kiplingi", feeds primarily on plant matter. None are known to feed on seeds or fruit. Extrafloral nectaries on plants, such as "Chamaecrista fasciculata" (partridge pea), provide jumping spiders with nectar; the plant benefits accordingly when the spiders prey on whatever pests they find.  The female of the southeast Asian species "Toxeus magnus" feeds its offspring with a milky nutritious fluid for the first 40 days of their life. Female offspring are also allowed some milk after sexual maturity.

Reproduction.

Courtship and mating behavior.

Jumping spiders conduct complex, visual courtship displays using both movements and physical bodily attributes. Unlike females, males possess plumose hairs, colored or iridescent hairs (particularly pronounced in the peacock spiders), front leg fringes, structures on other legs, and other, often bizarre, modifications. These characteristics are used in a courtship "dance" in which the colored or iridescent parts of the body are displayed. In addition to the display of colors, jumping spiders perform complex sliding, vibrational, or zigzag movements to attract females. It has also recently been discovered that many males have auditory signals as well. These amplified sounds presented to the females resemble buzzes or drum rolls. Species vary greatly in visual and vibratory components of courtship. Many species have patches of UV reflectance, which are exhibited in mature males. This visual component is used by some female jumping spiders for mate choice.  If receptive to the male, the female will assume a passive, crouching position. In some species, the female may also vibrate her palps or abdomen. The male will then extend his front legs towards the female to touch her. If the female remains receptive, the male will climb on the female's back and inseminate her with his palps.

Consequences of sexual dimorphism.

Maintaining colorful ornamentation may seem strictly beneficial to sexual selection, yet there are costs to maintain such distinguishing characteristics. While colorful or UV reflecting individuals may attract more female spiders, it can also increase the risk of predation.

Taxonomy.

The monophyly of the family Salticidae is well-established through both phylogenetic and morphological analyses, but no consensus exists on what other group of spiders are most closely related to the jumping spiders. Suggested sister groups have included the oxyopids (lynx spiders), thomisids (crab spiders), clubionoids (sac spiders), and web-building spiders. A 2017 phylogenetic analysis suggests that the sister group may be the family Miturgidae.  The taxonomy within the jumping spider family was significantly revised in 2015. The family is now divided into seven subfamilies:  Of these subfamilies, Salticinae is by far the largest, comprising over 90% of the known species of jumping spiders.

Models for mimicry.

Some small insects are thought to have evolved an appearance or behavioural traits that resemble those of jumping spiders and this is suspected to prevent their predation, specifically from jumping spiders. Some examples appear to be provided by patterns on the wings of some tephritid flies, the nymph of a fulgorid and possibly some moths.

Fossils.

Very few jumping spider fossils have been found. Of those known, all are from Cenozoic era amber. The oldest fossils are from Baltic amber dating to the Eocene epoch, specifically, 54 to 42 million years ago. Other fossil jumping spiders have been found in Chiapan amber and Dominican amber.

Jumping spiders are a group of spiders that constitute the family Salticidae. As of 2019, this family contained over 600 described genera and over 6000 described species, making it the largest family of spiders at 13% of all species. Jumping spiders have some of the best vision among arthropods and use it in courtship, hunting, and navigation. Although they normally move unobtrusively and fairly slowly, most species are capable of very agile jumps, notably when hunting, but sometimes in response to sudden threats or crossing long gaps. Both their book lungs and tracheal system are well-developed, and they use both systems (bimodal breathing). Jumping spiders are generally recognized by their eye pattern. All jumping spiders have four pairs of eyes, with the anterior median pair being particularly large.

蝇虎科或跳蛛科(学名:),又名“<unk>”(读音同“隙”),是蜘蛛目的一科,也是蝇虎总科的唯一科。