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Bud Selig

Allan Huber "Bud" Selig  (born July 30, 1934) is an American baseball executive who currently serves as the Commissioner Emeritus of Baseball. Previously, he served as the ninth Commissioner of Baseball from 1998 to 2015. He initially served as de facto acting commissioner beginning in 1992 in his capacity as chairman of the Major League Baseball (MLB) Executive Committee before being named the official commissioner in 1998. Selig oversaw baseball through the 1994 strike, the introduction of the wild card, interleague play, and the de facto merging of the National and American Leagues under the Office of the Commissioner. He was instrumental in organizing the World Baseball Classic in 2006. Selig also introduced revenue sharing. He is credited for the financial turnaround of baseball during his tenure with a 400 percent increase in the revenue of MLB and annual record breaking attendance.

During Selig's term of service, the use of steroids and other performance-enhancing drugs became a public issue. The Mitchell Report, commissioned by Selig, concluded that the MLB commissioners, club officials, the Players Association, and the players all share "to some extent in the responsibility for the steroid era." Following the release of the Mitchell Report, Congressman Cliff Stearns called publicly for Selig to step down as commissioner, citing his "glacial response" to the "growing stain on baseball." Selig has pledged on numerous occasions to rid baseball of performance-enhancing drugs, and has overseen and instituted many rule changes and penalties to that end.

A Milwaukee native, Selig was previously the owner and team president of the Milwaukee Brewers. The franchise, originally known as the Seattle Pilots, was acquired by Selig in bankruptcy court in 1970, and renamed after the minor league team of the same name that he had watched in his youth and had existed until the arrival of the Braves in Milwaukee in 1953. Selig was credited with keeping baseball in Milwaukee. The Brewers went to the 1982 World Series (but were defeated in seven games by the St. Louis Cardinals), and Selig won seven Organization of the Year awards during his tenure. Selig remains a resident of Milwaukee.

On January 17, 2008, Selig's contract was extended through 2012, after which he planned to retire, but he then decided to stay as commissioner until the end of the 2014 season, a move approved by the owners on January 12, 2012, which would take his leadership past his 80th birthday. Selig made $14.5 million in the 12-month period ending October 31, 2005. Selig announced on September 26, 2013, that he would retire in January 2015. On January 22, 2015, MLB announced that Selig would formally step down from the office when his current term expired on January 24, 2015. He was inducted into the Baseball Hall of Fame in 2017.

Early life
Selig was born in Milwaukee, and grew up in a Jewish family. His father, Ben Selig, had come to the United States from Romania with his family when he was four years old. Selig graduated from the University of Wisconsin–Madison with a B.A. in American history and political science in 1956. He served two years in the U.S. Army before working with his father who owned a car leasing business in Milwaukee. Selig continues to be involved in the automotive industry, serving as president of the Selig Executive Lease Company.

Selig's interest in baseball came from his mother. An immigrant from Ukraine, Marie Selig attended college, a rare accomplishment for a woman in the early 20th century, and became a school teacher. When Selig was only three, Marie began taking him and his older brother, Jerry, to Borchert Field, where the minor league Milwaukee Brewers played. When the Boston Braves relocated to Milwaukee in 1953, Selig switched allegiances, and eventually became the team's largest public stockholder. Selig was devastated when he learned that the Braves were going to leave Milwaukee in favor of Atlanta. In 1965, when the Braves left Milwaukee, he divested his stock in the team. As a youngster, Selig's favorite player was Hershel Martin. He developed a friendship with Hank Aaron, when the young player joined the Braves. The elder Selig's company provided loaner cars to Braves players, which gave the family access to the clubhouse and players. The pair later attended Green Bay Packers games together and sat together on the team plane.

Milwaukee Brewers owner
As a minority owner of the Milwaukee Braves, Selig founded the organization Teams, Inc., in an attempt to prevent the majority owners (based out of Chicago) from moving the club to a larger television market. This was challenged legally on the basis that no prior team relocations (in the modern era) left a city without a team. Prior movements had all originated in cities that were home to at least two teams. When his quest to keep the team in Milwaukee finally failed after the 1965 season, he changed the group's name to Milwaukee Brewers Baseball Club, Inc., after the minor league baseball team he grew up watching, and devoted himself to returning Major League Baseball to Milwaukee.

Selig arranged for major league games to be played at Milwaukee County Stadium. The first, a pre-season match-up between the Chicago White Sox and Minnesota Twins, drew more than 51,000 spectators. Selig followed this up by hosting nine White Sox regular-season games in 1968 and eleven in 1969. One of the games played in Milwaukee that year was against the expansion Seattle Pilots, the team that would become the Brewers. Those Milwaukee "home" games were phenomenally successful, with the handful of games accounting for about one-third of total White Sox home attendance.

To satisfy that fan base, Selig decided to purchase the White Sox (with the intention of moving them to Milwaukee) in 1969. He entered into an agreement to buy the club, but the American League vetoed the sale, preferring to keep an American League team in Chicago, which at the time was still America's second-largest city. Selig turned his attention to other franchises.

In 1970, he purchased the bankrupt Seattle Pilots franchise, moving them to his hometown and officially renaming the team the Brewers.

During Selig's tenure as club president, the Brewers participated in postseason play in 1981, when the team finished first in the American League East during the second half of the season, and in 1982, when the team made it to the World Series, under the leadership of future Hall of Famers Robin Yount and Paul Molitor. Under Selig's watch, the Brewers also won seven Organization of the Year awards. Selig was part of the owners' collusion in 1985–1987, resulting in the owners paying US$280 million in damages to the players.

Upon his assumption of the commissioner's role, Selig transferred his ownership interest in the Brewers to his daughter Wendy Selig-Prieb in order to remove any technical conflicts of interest, though it was widely presumed he maintained some hand in team operations. Although the team was sold to Los Angeles investor Mark Attanasio in 2005, questions remain regarding Selig's past involvement. Selig's defenders point to the poor management of the team after Selig-Prieb took control as proof that Selig was not working behind the scenes.

Selig was elected to the Wisconsin Athletic Hall of Fame in 2001.

On August 24, 2010, a statue of Selig, the Selig Monument, commissioned by Brewers owner Mark Attanasio and designed by artist Brian Maughan, was unveiled outside Miller Park in Milwaukee.

Acting Commissioner (1992–1998)
Selig became an increasingly vocal opponent of Commissioner Fay Vincent, and soon became the leader of a group of owners seeking his removal. Selig has never stated that the owners colluded, while Vincent has:

"The Union basically doesn't trust the ownership because collusion was a US$280 million theft by Selig and Jerry Reinsdorf of that money from the players. I mean, they rigged the signing of free agents. They got caught. They paid $280 million to the players. And I think that's polluted labor relations in baseball ever since it happened. I think it's the reason MLBPA executive director Donald Fehr has no trust in Selig."

Following an 18-9 no-confidence vote, Vincent resigned. Selig had by this time become chairman of the Executive Council of Major League Baseball, and as such became de facto acting commissioner.

His first major act was to institute the Wild Card and divisional playoff play, which has created much controversy amongst baseball fans. Those against the Wild Card see it as diminishing the importance of the pennant race and the regular season, with the true race often being for second rather than first place, while those in favor of it view it as an opportunity for teams to have a shot at the playoffs even when they have no chance of a first-place finish in their division, thus maintaining fan interest later in the season.

Selig suspended Cincinnati Reds owner Marge Schott for a year in 1993 for repeated racially insensitive and prejudicial remarks and actions. The same year, New York Yankees owner George Steinbrenner was reinstated from a lifelong suspension that was instituted by Selig's predecessor Fay Vincent. Pete Rose has claimed that he applied for reinstatement over the years and received no such consideration. Rose, along with his close friend and former teammate Mike Schmidt (who is a strong supporter of Rose's reinstatement into baseball), met with Selig in 2002, where Rose privately admitted to Selig (two years before going public with his admission) about betting on baseball. Bud Selig was a close friend of the late Bart Giamatti, who was the commissioner when Rose was first banned from the sport in 1989.

As acting commissioner, Selig represented MLB during the 1994 players strike and cancelled the World Series, marking the first time the annual event had not been staged since 1904.

Commissioner (1998–2015)
After a six-year search for a new commissioner, the owners voted to give Selig the title on a permanent basis midway through the 1998 season.

During his tenure the game avoided a third work stoppage in 2002, and has seen the implementation of interleague play.

Whereas in the past, the National and American leagues had separate administrative organizations (which, for example, allowed for the introduction of different rules such as the designated hitter), under Selig, Major League Baseball consolidated the administrative functions of both leagues into the Commissioner's Office in 2000. The last official presidents of the NL and AL were Leonard S. Coleman Jr. and Dr. Gene Budig respectively.

Reaction after September 11, 2001
On September 11, 2001, Selig ordered all baseball games postponed for a week because of the terror attacks on New York and Washington. The games were postponed not only out of respect and mourning for the victims, but also out of concern for the safety and security of fans and players.

2001 contraction attempt
After the conclusion of the 2001 World Series, Selig held a vote on contracting two teams, reportedly the Minnesota Twins and Montreal Expos. This action led to Selig (along with former Expos owner Jeffrey Loria) being sued for racketeering and conspiring with Loria to deliberately defraud the Expos minority owners. If found liable, the league could have been ordered to pay as much as $500 million in total damages. The judge ruled that the Expos could not be moved or contracted until the case was over. The case eventually went to arbitration and was settled out of court for an undisclosed sum.

A week after Selig's announcement, Hennepin County Judge Harry Seymour Crump issued a temporary restraining order that forced the Twins to honor their lease and play the 2002 season at the Metrodome. In August 2002, the effort to contract the Twins officially fizzled as players and owners reached a consensus on a new labor agreement which extended the team's Metrodome lease.

Changes to the MLB All-Star Game
The 2002 All-Star Game, played in Selig's hometown of Milwaukee, was tied 7–7 after nine innings, and remained tied after the bottom of the 11th inning. Due to the recent managerial trend of granting playing time to as many available players as possible within the regulation nine innings, both managers had used their entire roster. Concerned for the arms of the pitchers currently on the mound, Selig made the controversial decision to declare the game a tie, to the dissatisfaction of the Milwaukee fans. Selig later said that this call was "embarrassing" and that he was "tremendously saddened" by the outcome of the game.

Selig subsequently tried to reinvigorate the All-Star Game by awarding the winning league home-field advantage in the World Series; that practice was initiated in 2003 and continued through 2016. The 2003 All-Star Game had the same U.S. viewership as 2002 (9.5 rating; 17 share) and the ratings declined in 2004 (8.8 rating; 15 share) and 2005 (8.1 rating; 14 share). The American television audience increased in 2006 (9.3 rating; 16 share).

Disciplinary actions
On July 1, 2005, Selig suspended Texas Rangers pitcher Kenny Rogers for 20 games and fined him US$50,000. The punishment stemmed from an incident on June 29, 2005 during a Rangers pre-game warmup session, where Rogers had shoved two local news reporters and knocked one camera to the ground. One of the reporters resumed filming after picking up said camera, which angered Rogers into shoving him again, after grabbing and throwing the camera to the ground, kicking it. He was then led away by a teammate and later sent home by the Club. While an appeal of his suspension was pending, Rogers appeared at the 2005 All-Star Game in Detroit, where fans loudly booed him. On July 22, 2005, Selig heard Rogers' appeal of his suspension. Selig decided to uphold the 20 games, however, an independent arbitrator ruled that Selig had exceeded his authority and reduced it to 13 games, but upheld the fine.

Performance-enhancing drugs
In 2005, Selig faced Congress on the issue of steroids. After the Congressional hearings in early 2005, and with the scrutiny of the sports and national media upon this issue, Selig put forth a proposal for a stricter performance-enhancing drug testing regime to replace the current system. This proposal also included the banning of amphetamines, a first for the major North American sports leagues. The MLB Players Association and MLB reached an agreement in November on the new policy.

Selig's testimony on the subject has been contradictory. In 2005, Selig told reporters, "I never even heard about them [steroids] until 1998 or 1999. I ran a team and nobody was closer to their players and I never heard any comment from them.  It wasn't until 1998 or '99 that I heard the discussion." But a year later, testifying to Congress in 2006, Selig claimed personal credit for spotting the problem early: "In 1994, before anybody was really talking about steroids in baseball, we proposed a program of testing for such substances to the MLBPA. As early as 1998, I began formulating a strategic plan to eliminate the use of performance-enhancing substances from the game." During the 1988 ALCS, Oakland's Jose Canseco had been repeatedly taunted by Boston fans with a chant of "ster-oids, ster-oids, ster-oids." Speaking at the 2013 All-Star Game, Selig complained, "People say, 'Well, you were slow to react.' We were not slow to react. In fact, I heard that this morning, and it aggravated me all over again."

By early 2006, Selig was forced to deal with the issue of steroid use. On March 30, 2006, as a response to the controversy of the use of performance-enhancing drugs and the anticipated career home run record to be set by Barry Bonds, Selig asked former U.S. Senator George J. Mitchell to lead an independent investigation into the use of steroids in baseball's recent past. Joe Sheehan from Baseball Prospectus wrote that the commission has been focusing "blame for the era exclusively on uniformed personnel", and failing to investigate any role played by team ownership and management.

Much controversy surrounded Selig and his involvement in Bonds' all-time home run record chase. For months, speculation surrounded Selig and the possibility that he and Henry Aaron would not attend Bonds' games as he closed in on the record. Selig announced in July 2007 when Bonds was near 755 home runs that he would attend the games. Selig was in attendance for Bonds' record-tying home run against the San Diego Padres, sitting in Padres owner John Moores' private suite. When Bonds hit his 755th home run, Selig refused to applaud Bonds' accomplishment, instead choosing to keep his hands in his pockets and have a look of disdain on his face. Bud Selig also did not attend the San Francisco Giants' game on August 7 when Barry Bonds hit his record-breaking 756th home run against the Washington Nationals; after the event, Selig released a statement congratulating Bonds.

On December 13, 2007, former senator Mitchell released his report on the use of performance-enhancing substances by MLB players. The report names many current and former players who allegedly used performance-enhancing drugs during their careers.

Selig has been widely criticized for not taking an active enough role to stem the tide of steroid use in baseball until it had blossomed into a debilitating problem for the industry. Chicago Sun-Times columnist Jay Mariotti called Selig the "Steroids Commissioner." Selig has been called to Congress several times to testify on performance-enhancing drug use. Congressman Cliff Stearns said in December 2007 that Selig should resign because of use of performance-enhancing drugs in baseball during his tenure.

Post-season schedule
Selig's decision to extend the traditional post-season schedule into November in an attempt to increase Nielsen ratings was met with widespread disdain, both inside and outside the baseball community. Mike Scioscia, manager of the American League West Division Champion Los Angeles Angels, dismissed the decision as "Ridiculous. I don't know. Can I say it any clearer than that? We should have never had a day off last Wednesday. We should never have three days off after the season. You shouldn't even have two days off after the season."

Controversies
Selig has been embroiled in a number of controversial decisions during his tenure as commissioner. Notably, he has been accused of favoring the Milwaukee Brewers, his former team, such as he was during the 2001 contraction controversy when it was suggested the Minnesota Twins be one of two teams (the other being the Montreal Expos) to be contracted for economic reasons. Sportswriter Rob Dibble posted an open letter to Bud Selig, criticizing the plan for benefiting only the Brewers, noting that the contraction of the Twins would benefit the Brewers, as they would potentially claim the Twins' share of the upper Midwest market.

During the 2011 Los Angeles Dodgers ownership dispute, he was accused of not acting in good faith towards and treating the Dodgers differently from other teams when he rejected the television deal that Frank McCourt negotiated that intended to bring the franchise out of bankruptcy, claiming McCourt violated the Baseball Agreement. In comparison, no action was taken against New York Mets owner Fred Wilpon despite being in a similar position. United States bankruptcy judge Kevin Gross rendered a stern warning to Selig, stating: "Should the Commissioner falter in proving alleged wrongdoing, the Court may allow LAD (Los Angeles Dodgers) to take further, limited discovery." Some critics have used Selig's handling of the Dodgers to point out a double standard in treatment of MLB owners. More specifically in regards to the Mets, critics have accused Selig of favoritism towards the Mets due Selig's personal relationship with Wilpon, claiming that it motivated him to stall any possible removal of Wilpon as that club's principal owner.

Selig also notably failed to resolve a 6-year conflict between the San Francisco Giants and the Oakland Athletics regarding the Athletics' proposed move to San Jose. Selig established a blue-ribbon panel in 2009 to resolve the dispute; however, despite years to find a resolution, the blue-ribbon panel completely failed to make any progress toward resolving the issue, leading San Jose to sue MLB. The lawsuit, which is currently ongoing, questions the league's anti-trust exemption and its ability to enforce particular clubs' geographic territories. In addition, he blocked the sale of the Athletics in 1999 to an ownership group led by Bob Piccinini, then the CEO of Save Mart Supermarkets, and Joe Lacob, who would later purchase Golden State Warriors, from purchasing the Athletics in 2005. Both potential ownership groups were committed to keeping the team in Oakland that would render this territorial dispute meaningless. Instead, Selig permitted only Lew Wolff, his fraternity brother from college, and John J. Fisher to buy the team. The latter has since initiated the process to move the Athletics from Oakland to Las Vegas.

Term of service
On December 1, 2006, Selig announced that he would be retiring as commissioner of baseball upon the expiration of his contract in 2009. Selig earned $14.5 million from MLB over the timespan October 31, 2005 to October 31, 2006. However, in January 2008, Selig agreed to a three-year contract extension, announcing he planned to retire after the 2012 season. He further decided against retirement, and after a two-year extension for the previous deal was agreed to on January 12, 2012, it was announced that Selig would remain commissioner until the end of the 2014 season.

Post-Commissioner Activities
In 2021, Selig was appointed as "non-voting co-Chair" (with Jane Forbes Clark) for the December 2021 Early Baseball Era Committee meeting, to consider candidates for election to the Hall of Fame whose major contributions to the game took place prior to 1950. The committee elected Bud Fowler and Buck O'Neil.

Notable changes to Major League Baseball
Bud Selig has overseen the following changes in Major League Baseball:
 * Realignment of teams into three divisions per league, and the introduction of playoff wild card teams (1994)
 * Interleague play (1997)
 * Retired Jackie Robinson's uniform number, 42, across all MLB teams (1997)
 * Two additional franchises: the Arizona Diamondbacks and the Tampa Bay Devil Rays, now the Tampa Bay Rays (1998)
 * Transfer of the Milwaukee Brewers from the American League to the National League (1998)
 * Abolition of the American and National league offices and presidencies, and inclusion of all umpiring crews into a common pool for AL and NL games, instead of having separate pools per league (2000)
 * Unbalanced schedule (2001)
 * Home field advantage in the World Series granted to the winner of the All Star Game in the same season (2003)
 * Transfer of Montreal Expos franchise to Washington, D.C., becoming the Washington Nationals (2004)
 * Dedicating April 15 as Jackie Robinson Day (2004)
 * Stricter Major League Baseball performance-enhancing drug testing policy (2005)
 * World Baseball Classic (2006)
 * Introduction of instant replay in the event of a disputed home run call (2008)
 * Addition of a second wild-card playoff team in each league (2012)
 * Transfer of the Houston Astros from the National League to the American League (2013), as a condition of the sale of the team to Jim Crane, resulting in each league having the same number of teams (15) and interleague play throughout the season
 * Expanded instant replay (2014) and the institution of the manager challenge system

During Selig's terms as executive council chairman (from 1992–1998) and commissioner, new stadiums opened in Arizona, Atlanta, Cincinnati, Cleveland, Colorado, Detroit, Houston, Miami, Milwaukee, Minneapolis, New York City (Flushing, Queens and the Bronx), Philadelphia, Pittsburgh, San Diego, San Francisco, Seattle, Arlington, St. Louis, and Washington, D.C.

Israel Baseball League
Selig and his family served a supportive role on the advisory board of the Israel Baseball League during its inaugural season in 2007. In response to issues with the league's financial management, after the season, the Selig family requested that their names be removed from the list of board members.

Selig Experience
In May 2015, the Milwaukee Brewers honored Bud Selig with the unveiling of the Selig Experience exhibit at American Family Field (formerly Miller Park.) The Selig Experience is a fifteen-minute documentary showing Bud Selig's life and work for the Milwaukee Brewers.

Personal life
Selig has been married twice. He married his first wife, Donna Chaimson, in the 1950s, and they had two daughters: Sari (born 1957) and Wendy (born 1960). The couple divorced in 1976 after 19 years of marriage on the grounds that Selig had been "unduly absenting yourself from the home of the parties and isolating yourself ... in pursuit of your baseball interests to the detriment of your marriage." Chaimson later stated that the marriage ended because her husband "divorced me and married baseball." Since 1977, Selig has been married to the former Suzanne Steinman, who has a daughter from a previous marriage.

Teaching
In 2009, Selig began teaching as an adjunct professor of sports law and policy at Marquette University Law School. His classes have covered numerous topics, including "the history of collective bargaining and free agency, baseball's antitrust exemption, revenue sharing – as well as finer points of sports law like intellectual property rights, ambush marketing, and why baseball does not allow game footage on YouTube."

In 2010, Selig endowed the Allan H. Selig Chair in the History of Sport and Society in the United States, as well as a Distinguished Lecture Series in Sport and Society at his alma mater, the University of Wisconsin–Madison. The inaugural lecture was given by Adrian Burgos and Prof. Sean Dinces has held the chair since 2013.

In February 2016, Selig joined the Sandra Day O'Connor College of Law at Arizona State University.

Honors
Selig was awarded the U.S. Department of the Army Outstanding Civilian Service Award in April 2015 for supporting soldiers, veterans and their families through his work in Major League Baseball. On April 6, 2015, the Milwaukee Brewers retired uniform number 1 in his honor.

In 2014, Selig was inducted onto the inaugural Milwaukee Brewers Wall of Honor.

On December 4, 2016, it was announced Selig was elected into the National Baseball Hall of Fame Class of 2017. He was formally inducted on July 30, 2017.

In 2016, Selig was honored with the "Lombardi Award of Excellence" from the Vince Lombardi Cancer Foundation. The award was created to honor Coach Lombardi's legacy, and is awarded annually to an individual who exemplifies the spirit of the Coach.

Publications

 * Foreword to American Jews and America's Game: Voices of a Growing Legacy in Baseball by Larry Ruttman. Lincoln, Nebraska and London, England: University of Nebraska Press, 2013.

title: Bud Selig


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Bison

A bison (: bison) is a large bovine in the genus Bison (Greek: "wild ox" (bison) ) within the tribe Bovini. Two extant and numerous extinct species are recognised.

Of the two surviving species, the American bison, B. bison, found only in North America, is the more numerous. Although colloquially referred to as a buffalo in the United States and Canada, it is only distantly related to the true buffalo. The North American species is composed of two subspecies, the Plains bison, B. b. bison, and the wood bison, B. b. athabascae, which is the namesake of Wood Buffalo National Park in Canada. A third subspecies, the eastern bison (B. b. pennsylvanicus) is no longer considered a valid taxon, being a junior synonym of B. b. bison. References to "woods bison" or "wood bison" from the Eastern United States refer to this subspecies, not B. b. athabascae, which was not found in the region. The European bison, B. bonasus, or wisent, or zubr, or colloquially European buffalo, is found in Europe and the Caucasus, reintroduced after being extinct in the wild.

While bison species have been traditionally classified in their own genus, modern genetics indicates that they are nested within the genus Bos, which includes, among others, cattle, yaks and gaur, being most closely related to yaks. Bison are sometimes bred with domestic cattle and produce offspring called beefalo, in North America, or żubroń, in Poland.

Description

The American bison and the European bison (wisent) are the largest surviving terrestrial animals in North America and Europe. They are typical artiodactyl (cloven hooved) ungulates, and are similar in appearance to other bovines such as cattle and true buffalo. They are broad and muscular with shaggy coats of long hair. Adults grow up to 2 m in height and 3.5 m in length for American bison and up to 2.1 m in height and 2.9 m in length for European bison. American bison can weigh from around 400 to 1,270 kg and European bison can weigh from 800 to 1000 kg. European bison tend to be taller than American bison.

Bison are nomadic grazers and travel in herds. The bulls leave the herds of females at two or three years of age, and join a herd of males, which usually are smaller than female herds. Mature bulls rarely travel alone. Towards the end of the summer, for the reproductive season, the sexes necessarily commingle.

American bison are known for living in the Great Plains, but formerly had a much larger range, including much of the eastern United States and parts of Mexico. Both species were hunted close to extinction during the 19th and 20th centuries, but have since rebounded. The wisent in part owes its survival to the Chernobyl disaster, as the Chernobyl Exclusion Zone has become a kind of wildlife preserve for wisent and other rare megafauna such as the Przewalski's horse, though poaching has become a threat in recent years. The American Plains bison is no longer listed as endangered, but this does not mean the species is secure. Genetically pure B. b. bison currently number only about 20,000, separated into fragmented herds—all of which require active conservation measures. The wood bison is on the endangered species list in Canada and is listed as threatened in the United States, though numerous attempts have been made by beefalo ranchers to have it entirely removed from the Endangered Species List.

Although superficially similar, physical and behavioural differences exist between the American and European bison. The American species has 15 ribs, while the European bison has 14. The American bison has four lumbar vertebrae, while the European has five. (The difference in this case is that what would be the first lumbar vertebra has ribs attached to it in American bison and is thus counted as the 15th thoracic vertebra, compared to 14 thoracic vertebrae in wisent.) Adult American bison are less slim in build and have shorter legs. American bison tend to graze more, and browse less than their European relatives. Their anatomies reflect this behavioural difference; the American bison's head hangs lower than the European's. The body of the American bison is typically hairier, though its tail has less hair than that of the European bison. The horns of the European bison point through the plane of their faces, making them more adept at fighting through the interlocking of horns in the same manner as domestic cattle, unlike the American bison, which favours butting. American bison are more easily tamed than their European cousins, and breed with domestic cattle more readily.

Evolution and genetic history
The bovine tribe (Bovini) split about 5 to 10 million years ago into the buffalos (Bubalus and Syncerus) and a group leading to bison and taurine cattle. Genetic evidence from nuclear DNA indicates that the closest living relatives of bison are yaks, with bison being nested within the genus Bos, rendering Bos without including bison paraphyletic. While nuclear DNA indicates that both extant bison species are each other's closest living relatives, the mitochondrial DNA of European bison is more closely related to that of domestic cattle and aurochs (while the mitochondrial DNA of American bison is closely related to that of yaks). This discrepancy is either suggested to be the result of incomplete lineage sorting or ancient introgression. Bison are widely believed to have evolved from a lineage belonging to the extinct genus Leptobos during the Late Pliocene to Early Pleistocene in Asia. The earliest members of the bison lineage, known from the Late Pliocene to Early Pleistocene of the Indian Subcontinent (Bison sivalensis) and China (Bison palaeosinensis), approximately 3.4-2.6 million years ago (Ma) are placed in the subgenus Bison (Eobison). The oldest remains of Eobison in Europe are those Bison georgicus found in Dmanisi, Georgia, dated to around 1.76 Ma. More derived members of the genus are placed in the subgenus Bison (Bison), which first appeared towards the end of the Early Pleistocene, around 1.2 Ma, with early members of the subgenus including the widespread Bison schoetensacki.

The steppe bison (Bison priscus) first appeared during the mid-Middle Pleistocene in eastern Eurasia, and subsequently became widely distributed across Eurasia. During the late Middle Pleistocene, around 195,000-135,000 years ago, the steppe bison migrated across the Bering land bridge into North America, becoming ancestral to North American bison species, including the large Bison latifrons, and the smaller Bison antiquus, which became extinct at the end of the Late Pleistocene. Modern American bison are thought to have evolved from B. antiquus during the Late Pleistocene-Holocene transition via the intermediate form Bison occidentalis. The European bison, Bison bonasus, first appeared in Europe during the late Middle Pleistocene, where it existed in sympatry with the steppe bison. Its relationship with other extinct bison species is unclear, though it appears to be only distantly related to the steppe and American bisons, with possibly some interbreeding between the two lineages during the Middle Pleistocene. The steppe bison survived into the early-mid Holocene in Alaska-Yukon and eastern Siberia, before becoming extinct.

During the population bottleneck caused by the great slaughter of American bison during the 19th century, the number of bison remaining alive in North America declined to as low as 541. During that period, a handful of ranchers gathered remnants of the existing herds to save the species from extinction. These ranchers bred some of the bison with cattle in an effort to produce "cattleo" (today called "beefalo"). Accidental crossings were also known to occur. Generally, male domestic bulls were crossed with bison cows, producing offspring of which only the females were fertile. The crossbred animals did not demonstrate any form of hybrid vigor, so the practice was abandoned. Wisent-American bison hybrids were briefly experimented with in Germany (and found to be fully fertile) and a herd of such animals is maintained in Russia. A herd of cattle-wisent crossbreeds (zubron) is maintained in Poland. First-generation crosses do not occur naturally, requiring caesarean delivery. First-generation males are infertile. The U.S. National Bison Association has adopted a code of ethics that prohibits its members from deliberately crossbreeding bison with any other species. In the United States, many ranchers are now using DNA testing to cull the residual cattle genetics from their bison herds. The proportion of cattle DNA that has been measured in introgressed individuals and bison herds today is typically quite low, ranging from 0.56 to 1.8%.

There are also remnant purebred American bison herds on public lands in North America. Two subspecies of bison exist in North America: the plains bison and the wood bison. Herds of importance are found in Yellowstone National Park, Wind Cave National Park in South Dakota, Blue Mounds State Park in Minnesota, Elk Island National Park in Alberta, and Grasslands National Park in Saskatchewan. In 2015, a purebred herd of 350 individuals was identified on public lands in the Henry Mountains of southern Utah via genetic testing of mitochondrial and nuclear DNA. This study, published in 2015, also showed the Henry Mountains bison herd to be free of brucellosis, a bacterial disease that was imported with non-native domestic cattle to North America.

In 2021, the American Society of Mammalogists considered Bison to be a subgenus, and placed both bison species back into Bos.

Relationships of bovines based on nuclear DNA, after Sinding, et al. 2021.

Behavior
Wallowing is a common behavior of bison. A bison wallow is a shallow depression in the soil, either wet or dry. Bison roll in these depressions, covering themselves with mud or dust. Possible explanations suggested for wallowing behavior include grooming behavior associated with moulting, male-male interaction (typically rutting behavior), social behavior for group cohesion, play behavior, relief from skin irritation due to biting insects, reduction of ectoparasite load (ticks and lice), and thermoregulation. In the process of wallowing, bison may become infected by the fatal disease anthrax, which may occur naturally in the soil.

Bison temperament is often unpredictable. They usually appear peaceful, unconcerned, or even lazy, but they may attack without warning or apparent reason. They can move at speeds up to 35 mph and cover long distances at a lumbering gallop.

Their most obvious weapons are the horns borne by both males and females, but their massive heads can be used as battering rams, effectively using the momentum produced by what is a typical weight of 2000 to 2700 lb moving at 30 mph. The hind legs can also be used to kill or maim with devastating effect. In the words of early naturalists, they were dangerous, savage animals that feared no other animal and in prime condition could best any foe except for a brown bear or a pack of wolves.

The rutting, or mating, season lasts from June through September, with peak activity in July and August. At this time, the older bulls rejoin the herd, and fights often take place between bulls. The herd exhibits much restlessness during breeding season. The animals are belligerent, unpredictable, and most dangerous.

Habitat
American bison live in river valleys and on prairies and plains. Typical habitat is open or semiopen grasslands, as well as sagebrush, semiarid lands, and scrublands. Some lightly wooded areas are also known historically to have supported bison. They also graze in hilly or mountainous areas where the slopes are not steep. Although not particularly known as high-altitude animals, bison in the Yellowstone Park bison herd are frequently found at elevations above 8000 ft. The Henry Mountains bison herd is found on the plains around the Henry Mountains, Utah, as well as in mountain valleys of the Henry Mountains to an altitude of 10000 ft.

European bison most commonly live in lightly wooded to fully wooded areas as well as areas with increased shrubs and bushes. European bison can sometimes be found living on grasslands and plains as well.

Restrictions
Throughout most of their historical range, landowners have sought restrictions on free-ranging bison. Herds on private land are required to be fenced in.

In the state of Montana, free-ranging bison on public land are legally shot, due to transmission of disease to cattle and damage to public property.

In 2013, Montana legislative measures concerning the bison were proposed and passed, but opposed by Native American tribes as they impinged on sovereign tribal rights. Three such bills were vetoed by Steve Bullock, the governor of Montana. The bison's circumstances remain an issue of contention between Native American tribes and private landowners.

Diet
Bison are ruminants, able to ferment cellulose in a specialized stomach prior to digestion. Bison were once thought to almost exclusively consume grasses and sedges, but are now known to consume a wide-variety of plants including woody plants and herbaceous eudicots. Over the course of the year, bison shift which plants they select in their diet based on which plants have the highest protein or energy concentrations at a given time and will reliably consume the same species of plants across years. Protein concentrations of the plants they eat tend to be highest in the spring and decline thereafter, reaching their lowest in the winter. In Yellowstone National Park, bison browsed willows and cottonwoods, not only in the winter when few other plants are available, but also in the summer. Bison are thought to migrate to optimize their diet, and will concentrate their feeding on recently burned areas due to the higher quality forage that regrows after the burn. Wisent tend to browse on shrubs and low-hanging trees more often than do the American bison, which prefer grass to shrubbery and trees.

Reproduction
Female bison ("cows") typically reproduce after three years of age and can continue beyond 19 years of age. Cows produce calves annually as long as their nutrition is sufficient, but not after years when weight gain is low. Reproduction is dependent on a cow's mass and age. Heavier cows produce heavier calves (weighed in the fall at weaning), and weights of calves are lower for older cows (after age 8).

Predators
Owing to their size, bison have few predators. Five exceptions are humans, grey wolves, cougars, grizzly bears, and coyotes. Wolves generally take down a bison while in a pack, but cases of a single wolf killing bison have been reported. Grizzly bears also consume bison, often by driving off the pack and consuming the wolves' kill. Grizzly bears and coyotes also prey on bison calves. Historically and prehistorically, lions, cave lions, tigers, dire wolves, Smilodon, Homotherium, cave hyenas, and Neanderthals posed threats to bison.

Infections and illness
For American bison, a main illness is malignant catarrhal fever, though brucellosis is a serious concern in the Yellowstone Park bison herd. Bison in the Antelope Island bison herd are regularly inoculated against brucellosis, parasites, Clostridium infection, infectious bovine rhinotracheitis, and bovine vibriosis.

The major illnesses in European bison are foot-and-mouth disease and balanoposthitis. Inbreeding of a small population plays a role in a number of genetic defects and lowers immunity to disease; that poses greater risk to the population.

Name
Although called "buffalo" in American English, they are only distantly related to two "true buffalo", the Asian water buffalo and the African buffalo. Samuel de Champlain applied the French term buffle to the bison in 1616 (published 1619), after seeing skins and a drawing shown to him by members of the Nipissing First Nation, who said they travelled 40 days (from east of Lake Huron) to trade with another nation who hunted the animals. Though "bison" might be considered more scientifically correct, "buffalo" is also considered correct as a result of standard usage in American English, and is listed in many dictionaries as an acceptable name for American buffalo or bison. "Buffalo" has a much longer history than "bison", which was first recorded in 1774.

Human impact
Bison was a significant resource for indigenous peoples of North America for food and raw materials until near extinction in the late 19th century. For the indigenous peoples of the Plains, it was their principal food source. Native Americans highly valued their relationship with the bison and saw them as sacred, treating them respectfully to ensure their abundance and longevity. In his biography, Lakota teacher and elder John Fire Lame Deer describes the relationship as such:

"The buffalo gave us everything we needed. Without it we were nothing. Our tipis were made of his skin. His hide was our bed, our blanket, our winter coat. It was our drum, throbbing through the night, alive, holy. Out of his skin we made our water bags. His flesh strengthened us, became flesh of our flesh. Not the smallest part of it was wasted. His stomach, a red-hot stone dropped into it, became our soup kettle. His horns were our spoons, the bones our knives, our women's awls and needles. Out of his sinews we made our bowstrings and thread. His ribs were fashioned into sleds for our children, his hoofs became rattles. His mighty skull, with the pipe leaning against it, was our sacred altar. The name of the greatest of all Sioux was Tatanka Iyotake—Sitting Bull. When you killed off the buffalo you also killed the Indian—the real, natural, 'wild' Indian."

European colonials were almost exclusively accountable for the near-extinction of the American bison in the 1800s. At the beginning of the century, tens of millions of bison roamed North America. Colonists slaughtered an estimated 50 million bison during the 19th century, although the causes of decline and the numbers killed are disputed and debated. Railroads were advertising "hunting by rail", where trains encountered large herds alongside or crossing the tracks. Men aboard fired from the train's roof or windows, leaving countless animals to rot where they died. This overhunting was in part motivated by the U.S. government's desire to limit the range and power of indigenous plains Indians whose diets and cultures depended on the buffalo herds. The overhunting of the bison reduced their population to hundreds.

The American bison's nadir came in 1889, with an estimated population of only 1,091 animals (both wild and captive). Repopulation attempts via enforced protection of government herds and extensive ranching began in 1910 and have continued (with excellent success) to the present day, with some caveats. Extensive farming has increased the bison's population to nearly 150,000, and it is officially no longer considered an endangered species. However, from a genetic standpoint, most of these animals are actually hybrids with domestic cattle and only two populations in Yellowstone National Park in the United States and Elk Island National Park in Canada remain as genetically pure bison. These genetically pure animals account for only ~5% of the currently extant American bison population, reflecting the loss of most of the species' genetic diversity.

As of July 2015, an estimated 4,900 bison lived in Yellowstone National Park, the largest U.S. bison population on public land. During 1983–1985 visitors experienced 33 bison-related injuries (range = 10–13/year), so the park implemented education campaigns. After years of success, five injuries associated with bison encounters occurred in 2015, because visitors did not maintain the required distance of 75 ft (23 m) from bison while hiking or taking pictures.

Nutrition
Bison is an excellent source of complete protein and a rich source (20% or more of the Daily Value, DV) of multiple vitamins, including riboflavin, niacin, vitamin B6, and vitamin B12, and is also a rich source of minerals, including iron, phosphorus, and zinc. Additionally, bison is a good source (10% or more of the DV) of thiamine.

Livestock
The earliest plausible accounts of captive bison are those of the zoo at Tenochtitlan, the Aztec capital, which held an animal the Spaniards called "the Mexican bull". In 1552, Francisco Lopez de Gomara described Plains Indians herding and leading bison like cattle in his controversial book, Historia general de las Indias. Gomara, having never visited the Americas himself, likely misinterpreted early ethnographic accounts as the more familiar pastoralist relationship of the Old World. Today, bison are increasingly raised for meat, hides, wool, and dairy products. The majority of bison in the world are raised for human consumption or fur clothing. Bison meat is generally considered to taste very similar to beef, but is lower in fat and cholesterol, yet higher in protein than beef, which has led to the development of beefalo, a fertile hybrid of bison and domestic cattle. A market even exists for kosher bison meat; these bison are slaughtered at one of the few kosher mammal slaughterhouses in the U.S. and Canada, and the meat is then distributed worldwide.

In America, the commercial industry for bison has been slow to develop despite individuals, such as Ted Turner, who have long marketed bison meat. In the 1990s, Turner found limited success with restaurants for high-quality cuts of meat, which include bison steaks and tenderloin. Lower-quality cuts suitable for hamburger and hot dogs have been described as "almost nonexistent". This created a marketing problem for commercial farming because the majority of usable meat, about 400 pounds for each bison, is suitable for these products. In 2003, the United States Department of Agriculture purchased $10 million worth of frozen overstock to save the industry, which would later recover through better use of consumer marketing. Restaurants have played a role in popularizing bison meat, like Ted's Montana Grill, which added bison to their menus. Ruby Tuesday first offered bison on their menus in 2005.

In Canada, commercial bison farming began in the mid-1980s, concerning an unknown number of animals then. The first census of the bison occurred in 1996, which recorded 45,235 bison on 745 farms, and grew to 195,728 bison on 1,898 farms for the 2006 census.

Several pet food companies use bison as a red meat alternative in dog foods. The companies producing these formulas include Natural Balance Pet Foods, Freshpet, the Blue Buffalo Company, Solid Gold, Canidae, and Taste of the Wild (made by Diamond Pet Foods, Inc., owned by Schell and Kampeter, Inc.).

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Bison


text:
Baryon

In particle physics, a baryon is a type of composite subatomic particle, including the proton and the neutron, that contains an odd number of valence quarks, conventionally three. Baryons belong to the hadron family of particles; hadrons are composed of quarks. Baryons are also classified as fermions because they have half-integer spin.

The name "baryon", introduced by Abraham Pais, comes from the Greek word for "heavy" (βαρύς, barýs), because, at the time of their naming, most known elementary particles had lower masses than the baryons. Each baryon has a corresponding antiparticle (antibaryon) where their corresponding antiquarks replace quarks. For example, a proton is made of two up quarks and one down quark; and its corresponding antiparticle, the antiproton, is made of two up antiquarks and one down antiquark.

Baryons participate in the residual strong force, which is mediated by particles known as mesons. The most familiar baryons are protons and neutrons, both of which contain three quarks, and for this reason they are sometimes called triquarks. These particles make up most of the mass of the visible matter in the universe and compose the nucleus of every atom (electrons, the other major component of the atom, are members of a different family of particles called leptons; leptons do not interact via the strong force). Exotic baryons containing five quarks, called pentaquarks, have also been discovered and studied.

A census of the Universe's baryons indicates that 10% of them could be found inside galaxies, 50 to 60% in the circumgalactic medium, and the remaining 30 to 40% could be located in the warm–hot intergalactic medium (WHIM).

Background
Baryons are strongly interacting fermions; that is, they are acted on by the strong nuclear force and are described by Fermi–Dirac statistics, which apply to all particles obeying the Pauli exclusion principle. This is in contrast to the bosons, which do not obey the exclusion principle.

Baryons, alongside mesons, are hadrons, composite particles composed of quarks. Quarks have baryon numbers of B = $1⁄3$ and antiquarks have baryon numbers of B = −$1⁄3$. The term "baryon" usually refers to triquarks—baryons made of three quarks (B = $1⁄3$ + $1⁄3$ + $1⁄3$ = 1).

Other exotic baryons have been proposed, such as pentaquarks—baryons made of four quarks and one antiquark (B = $1⁄3$ + $1⁄3$ + $1⁄3$ + $1⁄3$ − $1⁄3$ = 1), but their existence is not generally accepted. The particle physics community as a whole did not view their existence as likely in 2006, and in 2008, considered evidence to be overwhelmingly against the existence of the reported pentaquarks. However, in July 2015, the LHCb experiment observed two resonances consistent with pentaquark states in the Λ$0 b$ → J/ψK$−$p decay, with a combined statistical significance of 15σ.

In theory, heptaquarks (5 quarks, 2 antiquarks), nonaquarks (6 quarks, 3 antiquarks), etc. could also exist.

Baryonic matter
Nearly all matter that may be encountered or experienced in everyday life is baryonic matter, which includes atoms of any sort, and provides them with the property of mass. Non-baryonic matter, as implied by the name, is any sort of matter that is not composed primarily of baryons. This might include neutrinos and free electrons, dark matter, supersymmetric particles, axions, and black holes.

The very existence of baryons is also a significant issue in cosmology because it is assumed that the Big Bang produced a state with equal amounts of baryons and antibaryons. The process by which baryons came to outnumber their antiparticles is called baryogenesis.

Baryogenesis
Experiments are consistent with the number of quarks in the universe being conserved alongside the total baryon number, with antibaryons being counted as negative quantities. Within the prevailing Standard Model of particle physics, the number of baryons may change in multiples of three due to the action of sphalerons, although this is rare and has not been observed under experiment. Some grand unified theories of particle physics also predict that a single proton can decay, changing the baryon number by one; however, this has not yet been observed under experiment. The excess of baryons over antibaryons in the present universe is thought to be due to non-conservation of baryon number in the very early universe, though this is not well understood.

Isospin and charge

The concept of isospin was first proposed by Werner Heisenberg in 1932 to explain the similarities between protons and neutrons under the strong interaction. Although they had different electric charges, their masses were so similar that physicists believed they were the same particle. The different electric charges were explained as being the result of some unknown excitation similar to spin. This unknown excitation was later dubbed isospin by Eugene Wigner in 1937.

This belief lasted until Murray Gell-Mann proposed the quark model in 1964 (containing originally only the u, d, and s quarks). The success of the isospin model is now understood to be the result of the similar masses of u and d quarks. Since u and d quarks have similar masses, particles made of the same number then also have similar masses. The exact specific u and d quark composition determines the charge, as u quarks carry charge +$0 b$ while d quarks carry charge −$0 b→J/ψK$. For example, the four Deltas all have different charges ( (uuu), (uud),  (udd),  (ddd)), but have similar masses (~1,232 MeV/c2) as they are each made of a combination of three u or d quarks. Under the isospin model, they were considered to be a single particle in different charged states.

The mathematics of isospin was modeled after that of spin. Isospin projections varied in increments of 1 just like those of spin, and to each projection was associated a "charged state". Since the "Delta particle" had four "charged states", it was said to be of isospin I = $3⁄2$. Its "charged states", , , and , corresponded to the isospin projections I3 = +$1⁄2$, I3 = +$2⁄3$, I3 = −$1⁄3$, and I3 = −$3⁄2$, respectively. Another example is the "nucleon particle". As there were two nucleon "charged states", it was said to be of isospin $3⁄2$. The positive nucleon (proton) was identified with I3 = +$1⁄2$ and the neutral nucleon  (neutron) with I3 = −$1⁄2$. It was later noted that the isospin projections were related to the up and down quark content of particles by the relation:
 * $$I_\mathrm{3}=\frac{1}{2}[(n_\mathrm{u}-n_\mathrm{\bar{u}})-(n_\mathrm{d}-n_\mathrm{\bar{d}})],$$

where the n's are the number of up and down quarks and antiquarks.

In the "isospin picture", the four Deltas and the two nucleons were thought to be the different states of two particles. However, in the quark model, Deltas are different states of nucleons (the N++ or N− are forbidden by Pauli's exclusion principle). Isospin, although conveying an inaccurate picture of things, is still used to classify baryons, leading to unnatural and often confusing nomenclature.

Flavour quantum numbers
The strangeness flavour quantum number S (not to be confused with spin) was noticed to go up and down along with particle mass. The higher the mass, the lower the strangeness (the more s quarks). Particles could be described with isospin projections (related to charge) and strangeness (mass) (see the uds octet and decuplet figures on the right). As other quarks were discovered, new quantum numbers were made to have similar description of udc and udb octets and decuplets. Since only the u and d mass are similar, this description of particle mass and charge in terms of isospin and flavour quantum numbers works well only for octet and decuplet made of one u, one d, and one other quark, and breaks down for the other octets and decuplets (for example, ucb octet and decuplet). If the quarks all had the same mass, their behaviour would be called symmetric, as they would all behave in the same way to the strong interaction. Since quarks do not have the same mass, they do not interact in the same way (exactly like an electron placed in an electric field will accelerate more than a proton placed in the same field because of its lighter mass), and the symmetry is said to be broken.

It was noted that charge (Q) was related to the isospin projection (I3), the baryon number (B) and flavour quantum numbers (S, C, B′, T) by the Gell-Mann–Nishijima formula:
 * $$Q = I_3 +\frac{1}{2}\left(B + S + C + B^\prime + T\right),$$

where S, C, B′, and T represent the strangeness, charm, bottomness and topness flavour quantum numbers, respectively. They are related to the number of strange, charm, bottom, and top quarks and antiquark according to the relations:
 * $$\begin{align}

S &= -\left(n_\mathrm{s} - n_\mathrm{\bar{s}}\right), \\ C &= +\left(n_\mathrm{c} - n_\mathrm{\bar{c}}\right), \\ B^\prime &= -\left(n_\mathrm{b} - n_\mathrm{\bar{b}}\right), \\ T &= +\left(n_\mathrm{t} - n_\mathrm{\bar{t}}\right), \end{align}$$ meaning that the Gell-Mann–Nishijima formula is equivalent to the expression of charge in terms of quark content:
 * $$Q = \frac{2}{3}\left[(n_\mathrm{u} - n_\mathrm{\bar{u}}) + (n_\mathrm{c} - n_\mathrm{\bar{c}}) + (n_\mathrm{t} - n_\mathrm{\bar{t}})\right] - \frac{1}{3}\left[(n_\mathrm{d} - n_\mathrm{\bar{d}}) + (n_\mathrm{s} - n_\mathrm{\bar{s}}) + (n_\mathrm{b} - n_\mathrm{\bar{b}})\right].$$

Spin, orbital angular momentum, and total angular momentum
Spin (quantum number S) is a vector quantity that represents the "intrinsic" angular momentum of a particle. It comes in increments of $3⁄2$ ħ (pronounced "h-bar"). The ħ is often dropped because it is the "fundamental" unit of spin, and it is implied that "spin 1" means "spin 1 ħ". In some systems of natural units, ħ is chosen to be 1, and therefore does not appear anywhere.

Quarks are fermionic particles of spin $1⁄2$ (S = $1⁄2$). Because spin projections vary in increments of 1 (that is 1 ħ), a single quark has a spin vector of length $1⁄2$, and has two spin projections (Sz = +$1⁄2$ and Sz = −$1⁄2$). Two quarks can have their spins aligned, in which case the two spin vectors add to make a vector of length S = 1 and three spin projections (Sz = +1, Sz = 0, and Sz = −1). If two quarks have unaligned spins, the spin vectors add up to make a vector of length S = 0 and has only one spin projection (Sz = 0), etc. Since baryons are made of three quarks, their spin vectors can add to make a vector of length S = $1⁄2$, which has four spin projections (Sz = +$1⁄2$, Sz = +$1⁄2$, Sz = −$1⁄2$, and Sz = −$3⁄2$), or a vector of length S = $3⁄2$ with two spin projections (Sz = +$1⁄2$, and Sz = −$1⁄2$).

There is another quantity of angular momentum, called the orbital angular momentum (azimuthal quantum number L), that comes in increments of 1 ħ, which represent the angular moment due to quarks orbiting around each other. The total angular momentum (total angular momentum quantum number J) of a particle is therefore the combination of intrinsic angular momentum (spin) and orbital angular momentum. It can take any value from L − S to L + S, in increments of 1.

Particle physicists are most interested in baryons with no orbital angular momentum (L = 0), as they correspond to ground states—states of minimal energy. Therefore, the two groups of baryons most studied are the S = $3⁄2$; L = 0 and S = $1⁄2$; L = 0, which corresponds to J = $1⁄2$+ and J = $1⁄2$+, respectively, although they are not the only ones. It is also possible to obtain J = $1⁄2$+ particles from S = $1⁄2$ and L = 2, as well as S = $1⁄2$ and L = 2. This phenomenon of having multiple particles in the same total angular momentum configuration is called degeneracy. How to distinguish between these degenerate baryons is an active area of research in baryon spectroscopy.

Parity
If the universe were reflected in a mirror, most of the laws of physics would be identical—things would behave the same way regardless of what we call "left" and what we call "right". This concept of mirror reflection is called "intrinsic parity" or simply "parity" (P). Gravity, the electromagnetic force, and the strong interaction all behave in the same way regardless of whether or not the universe is reflected in a mirror, and thus are said to conserve parity (P-symmetry). However, the weak interaction does distinguish "left" from "right", a phenomenon called parity violation (P-violation).

Based on this, if the wavefunction for each particle (in more precise terms, the quantum field for each particle type) were simultaneously mirror-reversed, then the new set of wavefunctions would perfectly satisfy the laws of physics (apart from the weak interaction). It turns out that this is not quite true: for the equations to be satisfied, the wavefunctions of certain types of particles have to be multiplied by −1, in addition to being mirror-reversed. Such particle types are said to have negative or odd parity (P = −1, or alternatively P = –), while the other particles are said to have positive or even parity (P = +1, or alternatively P = +).

For baryons, the parity is related to the orbital angular momentum by the relation:
 * $$P=(-1)^L.\ $$

As a consequence, baryons with no orbital angular momentum (L = 0) all have even parity (P = +).

Nomenclature
Baryons are classified into groups according to their isospin (I) values and quark (q) content. There are six groups of baryons: nucleon, Delta , Lambda , Sigma , Xi , and Omega. The rules for classification are defined by the Particle Data Group. These rules consider the up, down and strange  quarks to be light and the charm , bottom , and top  quarks to be heavy. The rules cover all the particles that can be made from three of each of the six quarks, even though baryons made of top quarks are not expected to exist because of the top quark's short lifetime. The rules do not cover pentaquarks.
 * Baryons with (any combination of) three and/or  quarks are s (I = $3⁄2$) or  baryons (I = $1⁄2$).
 * Baryons containing two and/or  quarks are  baryons (I = 0) or  baryons (I = 1). If the third quark is heavy, its identity is given by a subscript.
 * Baryons containing one or  quark are  baryons (I = $3⁄2$). One or two subscripts are used if one or both of the remaining quarks are heavy.
 * Baryons containing no or  quarks are  baryons (I = 0), and subscripts indicate any heavy quark content.
 * Baryons that decay strongly have their masses as part of their names. For example, Σ0 does not decay strongly, but Δ++(1232) does.

It is also a widespread (but not universal) practice to follow some additional rules when distinguishing between some states that would otherwise have the same symbol.
 * Baryons in total angular momentum J = $1⁄2$ configuration that have the same symbols as their J = $5⁄2$ counterparts are denoted by an asterisk ( * ).
 * Two baryons can be made of three different quarks in J = $3⁄2$ configuration. In this case, a prime ( ′ ) is used to distinguish between them.
 * Exception: When two of the three quarks are one up and one down quark, one baryon is dubbed Λ while the other is dubbed Σ.

Quarks carry a charge, so knowing the charge of a particle indirectly gives the quark content. For example, the rules above say that a contains a c quark and some combination of two u and/or d quarks. The c quark has a charge of (Q = +$5⁄2$), therefore the other two must be a u quark (Q = +$3⁄2$), and a d quark (Q = −$7⁄2$) to have the correct total charge (Q = +1).

title: Baryon


text:
Talk:Baryon

Elementary
My references say that baryons are elementary particles, they consist of quarks and cannot be broken down. Mesons also fit this description.

Two web sources for you to examine - and

Also my dictionary says: Hadron Pronunciation: (had'ron), [key] —n. Physics.

any elementary particle that is subject to the strong interaction. Hadrons are subdivided into baryons and mesons. Cf. quark.

All the sources I've seen don't call baryons as elementary particles, because they are composites, even if they can't be physically ripped apart. I would guess the usage varies, and so suggest that they not be called elementary.

Give some citations - I'm sure we can sort it out. I've given three, but I acknowledge that they are all quoting generalist literature. By the way, the link to boson simply redirects to particle physics... surely they deserve their own article. - MMGB

 * Elementary refers to any particle which is not composed of smaller particles. "Broken down" is not meant in a physical sense. There are exactly 16 elementary particles known to date: 6 quarks, 6 leptons, and 4 gauge bosons (not including antiparticles or gluon flavors). The jury is still out on the Higgs boson and the graviton. See http://www.neutron.anl.gov/hyper-physics/Particles.html for a good diagram -- Xaonon

Well I guess this is a case where infoplease got it wrong - some other sources I have checked confirm this position. If/When we have an article on elementary particles this confusion should be addressed directly.

Someone mentioned that mesons may be a superposition of quark-antiquark pairs, but I think it would be less confusing and more accurate to describe them as a pair where each of the quark and antiquarks may be in a superposition of states (colors and generations). Does this sound fair?

Does anyone know the mass of a baryon? Is it just the mass of a proton? or neutron? --PY

 * It varies between different types of baryon. If a specific baryon is a proton, then it has the mass of a proton; if a neutron, then it has the mass of a neutron; and so on. -- Paul A

PY, I believe that you are assuming that the baryon is a particle when it is actually a classification of particles. There are dozens of different baryons, each with its own mass.

Keep in mind that there was not a general consensus that hadrons were made of quarks until the mid-1970s. Older references could well describe them as elementary particles simply because their constituents were undiscovered or not generally accepted; even today they are sometimes called elementary particles because of a kind of language inertia. But we probably shouldn't call them that. --Matt McIrvin 00:29, 1 Oct 2004 (UTC)

Include table?
This article lacks a table summarising the properties of the mentioned baryons. Obviously a comprehensive table of known baryons would be a bit too large for the article. :) But something like this might be nice: http://hyperphysics.phy-astr.gsu.edu/hbase/particles/baryon.html

A mention of the quantum numbers associated with baryons would be nice as well. (Baryon number, strangeness etc.)

Here's a first attempt, perhaps someone can check that there are no errors in it? (Either of fact or of format :) ). It includes all of the baryons mentioned in the article, in the order mentioned.

1at least 1030

It looks fine to me, except that some numbers aren't being written in proper scientific notation. Instead of 0.6×10-23, for example, it should be 6x10-24. I would edit it myself, but I haven't quite had the time to thoroughly look through the editing system.

 * The numbers are written that way so you can more easily compare the decay times of related particles. Tho in the case you cited (the Deltas), none of the related particles seem to have made the table, so there's no reason that one should be in a funny format. -- Xerxes 14:52, 2005 Mar 10 (UTC)

After reading your post, I edited the scientific notation of the Deltas.

Are you sure that the neutron has a half-life of nine hundred and twenty seconds? That seems awfully short. Didn't someone have to build a really, really big detector to try to determine the half-life, because it was extremely long? [...] Okay, I looked it up, and neutrons do decay that quickly, but only when not bound inside nuclei. Should this be mentioned? I was led to the impression that we should all be big masses of Hydrogen-1 by now. grendel|khan 23:23, 2005 Mar 11 (UTC)

Thank you to the author of this article. You did a great job explaining in detail the topic; yet not too esoteric that someone without a strong background in physics won't understand the information (such as I). --jorgekluney

Number of baryons
Baryons are made from 3 quarks, any quarks. Since there are 6 different quarks, then we have 6^3 combinations of 3 quarks. However, from the Delta+ and the proton, each with quark composition u/u/d, it looks like the spin orientation have to be taken into account. Since each quark can be in +1/2 or -1/2 isospin state, then we have 12 different quarks/quarkstates possible for each of the three quarks, which gives us 12^3 different combinations of three quarks. If we remove the degeneracies (such as ssd (3/2),sds(3/2),dss(3/2)), then we have 364 (12+11+10...+11+10+9...+10+9+8+...3+2+1+2+1+1) distinct combination of quarks/quarkstates.

Now I'm not sure of this, but I think that it is the modulus of the spin that is important, so particles with spin -3/2 and -1/2 really are the same than the particles with spin 3/2 and spin 1/2. Removing these degeneracies leaves us with half the particles, and thus there are 182 distinct baryons that can be made from three quarks.

Did I understand it correctly? It would also be interesting if someone updated the list of baryons to take into account all the possibilities, with placeholders for the undiscovered particles Headbomb 22:11, 22 March 2008 (UTC)

bottom baryons, charmed baryons, where are they?
The article makes no mention of baryons with heavy quark content. See for example the summary page from the Review of Particle Physics ( W.-M. Yao et al., Journal of Physics G 33, 1 (2006) ). Erkcan 16:48, 24 July 2006 (UTC)
 * Sorry, it does mention at the very bottom, but the description mentions nucleons and hyperons only. Erkcan 16:51, 24 July 2006 (UTC)

Charmed baryons also have their own page -- I'll add a link to it. I'm not convinced that it should be a separate page (as opposed to a section within this one) but since it's nearly empty it's a moot point for now. As far as the ordering within this page goes, I think that introducing the light baryons and the octet+decuplet first and bringing up heavy flavours later is the right thing to do; isospin and strangeness are complicated enough without adding a third dimension right off the bat. Do you have any thoughts on what a heavy baryon section should cover? I had trouble coming up with a middle ground between "very vague" and "painful detail". Physicsdog 07:41, 27 July 2006 (UTC)

 * I also think that charmed and bottom baryons should be a section here. As for what should go in that section, I haven't got a good suggestion yet. As for the ordering within the page, I have no objection to your logic, but the current description (at the very top) seems to be misleading: It reads as if baryons = nucleons + hyperons. Just few sentences below it again says baryons = nucleons + lambda, omega, xi, delta. I understand that we might not want to go into c and b baryons right away, but IMHO the article looks somewhat inconsistent at the moment. Erkcan 16:04, 28 July 2006 (UTC)

baryons, mesons, and hadrons
I moved the following text from the article to here:
 * -- Here it says Baryons and Mesons are known as Hadrons, but then it says mesons are a type of bosons. Are bosons Hadrons or are hadrons bosons, etc....

Kingdon 16:21, 10 May 2007 (UTC)

In cosmology
In cosmology, it seems that baryonic matter can refer to both protons and electrons:
 * [Electrons and protons] are often grouped together and called baryons, nomenclature which is obviously ridiculous (electrons are leptons, not baryons) but nonetheless common.
 * -Dodelson, Modern Cosmology

Is this a common enough practice to mention in the article? --Starwed (talk) 11:47, 28 February 2008 (UTC)

 * This is very common practice in cosmology, and astrophysics in general. "Baryonic matter" basically refers to anything which is not dark matter or dark energy. I am surprised it is not mentioned in the article. Slauhale (talk) 22:59, 10 October 2018 (UTC)

Strangeness Convention
Please note that the diagrams (black-and-white, with pink circles for the states) in the "isospin" and the "baryons" page show the value of the strangeness opposite of the standard convention (which in turn is followed in the "mesons" page and the table above, under the "Include Table?" heading. For example, the Omega- baryon has strangeness -3, but is in the diagram on the "baryons" and the "isospin" pages is shown to have strangeness "3", with the strangeness axis oriented downward. I do not know enough about this wiki editing system to edit the figures and fix this. Tristan (talk) 02:42, 3 October 2009 (UTC)

Hadron overhaul
Please give input at Talk:Hadron. Thanks. Headbomb {{{sup|ταλκ}}κοντριβς – WP Physics} 02:01, 24 January 2010 (UTC)

Delta parity
The article states that the intrinsic parity of a baryon is (-1)^L and therefore the parity of all ground state baryons is positive. It would be useful if some expert on the subject added some scattering process where the relative parity between a Nucleon and a Delta becomes determined. Otherwise the statement seems a little bit unsubstantiated. Kotika98 (talk) 14:34, 6 July 2010 (UTC)

Delta spin
The Delta ( (uuu)) has the spin of all three quarks aligned. What is the particle formed when one of the quarks is anti-parallel to the others? It should have spin 1/2, yet doesn't appear in the octet. Why is that? --Michael C. Price talk 10:02, 19 October 2010 (UTC)

First Sentence
"A baryon be a composite particle made of three quarks." What are we, pirates? Hahaha. Fixing it now, but it was too funny not to point out. Bugbrain 04 (talk) 00:49, 28 January 2011 (UTC)

Baryons have no gluons
I'm glad that this article makes no mention of the fanciful claim that Baryons might possibly contain gluons that would then contribute to their total masses, like say the proton article does. Hcobb (talk) 15:18, 9 January 2012 (UTC)
 * If emission and absorption of (virtual) gluons by quarks would not take place in baryons, they wouldn't be stable. And the analysis of the structure functions obtained from deep inelastic scattering of electrons and neutrinos by nucleons shows that 1/2 of the nucleon momentum is carried by particles that interact neither electromagnetically nor weakly (like quarks do). So why do you consider identifying these particles with the gluons fanciful? Impulseigenzustand (talk) 04:09, 16 July 2013 (UTC)

a single quark has a spin vector of length 1⁄2
I know what the author of this wants to say, but it is not correct. The quantum number S is 1/2, the length of the vector is ħ*sqrt(S(S+1)) != S. Impulseigenzustand (talk) 04:16, 16 July 2013 (UTC)

Why does Pauli exclusion principle prohibit nucleon with charge +2 ?
The parenthetical remark in the following fragment of the article confused me:
 * In the "isospin picture", the four Deltas and the two nucleons were thought to be the different states of two particles. However in the quark model, Deltas are different states of nucleons (the N++ or N− are forbidden by Pauli's exclusion principle). Isospin, although conveying an inaccurate picture of things, is still used to classify baryons, leading to unnatural and often confusing nomenclature.

As I understood the rest of the article, the difference between Δ (Delta-particles) and N (nucleons) is their spin. In a Δ the spins of the quarks are aligned to give S = 3/2, while in an N one quark has an opposite spin to the other quarks, giving S = 1/2. So the quarks are more similar in a Δ, leading to the question why does Pauli apply to N and not to Δ? Perhaps this needs to be clarified somewhere. -- Jitse Niesen (talk) 10:19, 14 August 2013 (UTC)

 * I'm not really sure what your background is, but Pauli, in a more formal way, means that baryons need to be overall antisymmetric with respect to the exchange of any two of its constituents. The degrees of liberty involved are space, color, flavour, and spin. For spin = 1/2 (as in nucleons), the spatial part is symmetrical. Color is always antisymmetrical (rgb - rbg - grb + gbr + brg - bgr) [exchange the first letter with the second letter, and you obtain the same thing with a - sign [grb - brg - rgb + bgr + rbg - gbr)]. Spin and flavour are individually of mixed symmetry, and together symmetrical (very long term, so I won't bother writing it down).

 * If you wanted a N++, its flavour part would necessarily be symmetrical (uuu), which means spin would need to be symmetrical. But you cannot make an symmetrical spin 1/2 part, you can only make those with mixed symmetries. So you cannot have uuu (analogue of the Δ++) or ddd (analogue of the Δ−), or sss (which would be the analogue of the Ω−), or any baryons with the same three quarks in a spin-1/2 configuration.

 * If you need to read more on it, I would suggest ISBN 978-0471164333 and ISBN 978-0471164357 (to get how spin and symmetries work), and then ISBN 978-3527406012 for how that works with light baryons and mesons. I would recommend my own thesis [G. Landry, (2013), "Symétries et nomenclature des baryons: Proposition d'une nouvelle nomenclature", (Université de Moncton).], as it directly tackles this stuff in more details than you would usually encounter, but it's a thesis, which can be annoying to obtain, and it's in French, which you may not understand. Headbomb {talk / contribs / physics / books} 21:45, 14 August 2013 (UTC)

Thanks. That's very helpful in pointing out the right direction. I did one university course on quantum mechanics a dozen years ago, which covered some of this stuff, but not in great detail and I forgot most of it. My mistake was in supposing that the Pauli principle has the narrow meaning of "no two in the same state", while - as I now saw, rather embarrassingly, in the second (!) sentence of Pauli exclusion principle - it refers to the anti-symmetry of the wave function. -- Jitse Niesen (talk) 11:34, 15 August 2013 (UTC)

 * Note that "no two in the same state" follows from antisymmetry. Take for example, the following antisymmetric state
 * $$\frac{1}{\sqrt{2}}\left( |ud \rangle - | du \rangle \right)$$
 * What happens if you substitute u for d (or vice-versa)? This becomes 0 (i.e. it's a forbidden state). Headbomb {talk / contribs / physics / books} 15:10, 15 August 2013 (UTC)

Binding energy and mass

 * The success of the isospin model is now understood to be the result of the similar masses of the u and d quarks.

Isn't most of the mass of baryons the mass-energy of strong interaction? --130.233.162.130 (talk) 12:42, 8 November 2013 (UTC)
 * Yes, but the reason why the proton (N+) and neutron (N0) [for example] have similiar masses of roughly 939 MeV/c2 is because the up and down quarks have similar masses. If you change the proton's down quark to a strange quark (uud → uus), you get a Σ+ baryon which is much more massive (roughly 1190 MeV/c2), in great part because the strange quark is more massive than the down quarks. Headbomb {talk / contribs / physics / books} 12:58, 8 November 2013 (UTC)
 * Weinberg's QFT v.2 disagrees:
 * "It is striking that the masses of the charged an neutral pions turn out to be equal, even though we have made no assumption about the ratio of $m_{u}$ and $m_{d}$. We shall see below that this ratio is not near unity; isospin is a good quantum number not because the $u$ and $d$ quark masses are nearly equal, but because they are small."
 * I believe this sentence is actually wrong, and instead needs a link to chiral symmetry breaking or chiral perturbation theory with an explanation that the success is now understood to be a result of the small masses of the u and d quarks. Patricius12 (talk) 22:28, 5 November 2022 (UTC)

Star Trek use of the word baryons/baryon
Does any science-minded person who knows Star Trek well know whether it uses the word baryons/baryon in a similar or same way as current science? (It has been said that Star Trek (by some point) often tried to accurately use real science (as known then) mixed with Star-Trek-universe science.) The more info (and in layman's terms) about its use of this, the better. Thanks! Misty MH (talk) 02:40, 17 February 2014 (UTC)

Assessment comment
Substituted at 09:03, 29 April 2016 (UTC)

t Baryons?
Ok, so t quarks are expected to be unstable, and thus no baryons including them are expected to be stable. My question is this: do these hypothetical baryon configurations have supporting research and names? The article doesn't really speak to this, and my feeling is that it should, since my understanding is that a baryon by definition includes these cases, even if they are not realized in nature.

In other words, the current article is somewhat dismissive, without being thorough. I don't really doubt that these particles aren't realized, but I feel a responsible article on baryon should stick to the definition, and not be dismissive of classes that fit the definition. I also don't feel like it should breathlessly wait for experiments to determine whether they exist or not. That doesn't seem necessary or useful, although experimental results about existence are definitely noteworthy. 75.139.254.117 (talk) 22:50, 28 December 2016 (UTC)

 * They have names yes (the usual heavy baryon name rules, originally outlined in the 1986 Review of Particle Physics, e.g. Λt is a Lambda with one s quark replaced by a t quark), but as far as research goes, it's a bit like Element 10000 (highest so far is Element 118 and most doubt it's possible to create them beyond Element 173 or so). No one's found them, no one's expecting to be found, and if they could somehow form, they would be so excruciatingly difficult to produce and detect that we couldn't neither make them nor detect them. Headbomb {talk / contribs / physics / books} 02:45, 29 December 2016 (UTC)

Drawing attention to a related discussion on Baryon terminology
Editors on this page may want to contribute at: Talk:Exotic baryon.

Thanks! FT2 (Talk 18:17, 24 September 2018 (UTC)

Why an odd number of valence quarks ?
Why an odd number (to get spin 1/2?) and why 'valence' ?

Valence quark redirects to quark model but neither clearly explain what they are. Are the non-valence quarks just the virtual quarks in the gluon binding ? Are all three uud quarks in a proton considered 'valence'? Do we need 'valence' in the first sentence ? Are tetraquarks (with an even number of quarks) baryons or not ? - Rod57 (talk) 11:46, 2 April 2021 (UTC)

There's an argument that hadron may be a better redirect than quark model for valence quark. One can think of valence quarks as the real interacting bound quarks and non-valence quarks as virtual quarks created temporarily by gluon splitting in the course of the valence quarks interacting. uud = the valence quarks of a proton. A tetraquark is more closely related to a meson while pentaquarks are more closely related to baryons. Advolvens (talk) 23:16, 4 April 2021 (UTC)

Baryonic budget
As of 2011, more than 40% of the total baryonic budget had not been discovered yet in "representative samples of the universe, found in large galaxy clusters".( which also cites A.Simionescu (2011), Baryons in the outskirts of the X-ray brightest galaxy clusters, in ''Proceedings, Exploring the X-Ray Universe: Suzaku and Beyond (SUZAKU 2011(: Palo Alto, USA, July 20-22, 2011, 5-12).

title: Talk:Baryon


text:
Talk:Byzantine fire

A google search turned up 4,590 for Greek fire and 46 for Byzantine fire. I think that the Byzantine fire version is mainly from the game Age of Empires. Not, shall we say, a reliable source. ; ) --MichaelTinkler
 * was it like Greek Fire (although I think we know how that was made...)? edit conflict here -- I think Greek fire was made with pitch and other nasty sticky stuff...JHK

title: Talk:Byzantine fire