title: 2015 Formula One World Championship

text: Mercedes began the season with a one–two finish in Australia, resulting in a twenty-eight-point lead after just one round. They finished over thirty seconds clear of Sebastian Vettel, who finished third and secured a podium finish in his first race with Ferrari. Red Bull's Daniel Ricciardo finished a lap down in sixth, prompting the team to continue to voice their frustrations with Renault, as they were forced to use its second of four allotted power units for Ricciardo on the very first day of the season. The team also voiced its displeasure over the progress Renault had made in terms of power, with the team principal, Christian Horner, saying the Renault Energy F1-2015 was still down on Mercedes's PU106B Hybrid. After the race, the Red Bull team advisor Helmut Marko suggested that Red Bull might exit Formula One entirely if changes to the regulations were not made to level the field or cut development costs. Renault countered with their own threat to pull out of Formula One as an engine supplier if its reputation continued to be damaged or if its participation was otherwise not profitable to the company. Mercedes followed up by finishing second and third in Malaysia, while Red Bull continued to struggle, rounding out the top ten a lap down. After four rounds, Mercedes led the field, having earned 159 points (with Lewis Hamilton acquiring 93 out of 100 possible points), while Red Bull's struggles continued. The team acquired twenty-six points, enough for a distant fourth, and Ricciardo entered the European stages of the season on his fourth and final permissible power unit with fifteen events remaining on the calendar.


title: 2015 Formula One World Championship

text: With McLaren's longest continuous testing session lasting twelve laps in Montmeló – a total of , a sixth of a total Grand Prix distance – before running into engine trouble, Honda elected to detune the power units for the opening Grands Prix in an effort to improve reliability and longevity while the manufacturer worked to improve these areas before homologation. After both cars qualified on the back row, Kevin Magnussen failed to reach the grid after suffering an abrupt engine failure while on his way from the pit lane to the grid. Jenson Button managed to finish the race, albeit in the last classified position, two laps behind the leaders. Magnussen relinquished his seat back to Alonso in Malaysia; both cars qualified ahead of only the Manor Marussia cars and eventually retired. The team showed signs of improvement in terms of performance and was able to compete with the midfield cars in China and Bahrain, although reliability continued to prove troublesome as Button's car was unable to compete in the latter Grand Prix.


title: 2015 Formula One World Championship

text: Following a tumultuous pre-season in which they went through a period of administration and were saved by late investment, Manor Marussia arrived in Melbourne with a car that had passed its mandatory crash tests but had completed no testing. After the team's arrival in Australia, while assembling the cars, it was discovered that their computers had been wiped completely clean of all data in preparation for auction, and they ultimately could not compete in the Grand Prix. The team managed to get their cars running and on the racetrack by the second round in Malaysia, and were able to set times within 107% of the leading times in practice, giving stewards reasonable grounds to allow the team to race when they failed to do so in qualifying. Merhi was able to finish the race three laps down in fifteenth, while Stevens did not start. Manor Marussia continued to show signs of consistency, with both cars qualifying within 107%, starting, and finishing both Grands Prix in China and Bahrain. They were one of two teams, the other being McLaren, to return to Europe without a championship point.


title: 2015 Formula One World Championship

text: Ferrari came into the season seemingly much more competitive than the previous season, finishing on the podium in the opening race. Kimi Räikkönen said the SF15-T was "much better" to drive than 2014's F14 T. In Malaysia, Vettel won comfortably and Räikkönen finished in fourth, despite suffering a tyre failure. The team then finished third and fourth in China and Räikkönen secured his first podium appearance since rejoining Ferrari the previous season with a second-place finish in Bahrain. With 107 points, the team returned to Europe 52 points behind Mercedes, and 46 points ahead of Williams, who were third. Sauber left the opening rounds with their first points since .


title: 2015 Formula One World Championship

text: Mercedes arrived at Spain already with a comfortable lead. Lewis Hamilton had scored ninety-three points out of a possible one hundred, giving him a twenty-seven-point lead over his teammate Nico Rosberg entering the eight-race European portion of the season.


title: 2015 Formula One World Championship

text: Rosberg quickly cut into Hamilton's championship lead by securing victories in Spain (reducing his deficit to twenty points) and Monaco. The latter win was aided by the result of a costly miscalculation by the Mercedes team to pit Hamilton with a 19-second lead during a safety car period (that briefly saw the use of the "Virtual Safety Car" for the first time in F1's history) with 14 laps remaining. Rosberg and Sebastian Vettel did not make pit stops, allowing both to narrowly pass Hamilton by the pit lane exit. Racing resumed on lap seventy-one and Rosberg quickly pulled away, remaining in the lead until the chequered flag. Vettel held off Hamilton for second and third, respectively. As a result, Hamilton's lead over Rosberg in the Drivers' Championship was cut in half, to just ten points. Meanwhile, Button secured McLaren's first points of the season by finishing eighth. This left the Marussia drivers of Stevens and Merhi, along with the other McLaren driver, Fernando Alonso, as the only full-time drivers not to score a point after seven rounds.


title: 2015 Formula One World Championship

text: At the following Grands Prix in Canada, Austria, and Britain, Mercedes put to rest the criticism following the result in Monaco through finishing first and second in the next three races, extending their championship lead to 160 points over Ferrari. Williams collected their first two podiums of the season in the form of third-place results by Valtteri Bottas in Canada and Felipe Massa in Austria, while Ferrari lost ground to Mercedes following a retirement in Austria and an eighth-place finish in Britain by Räikkönen. Other power unit manufacturers continued to struggle, with a Renault-powered car finishing in the top five only once, in Monaco, indicating their continued lack of power. Honda continued to have reliability issues and, up to the British Grand Prix, suffered nine retirements and two failures to start due to power unit problems, translating to only seven overall finishes out of 18 possible results.


title: 2015 Formula One World Championship

text: The Drivers' Championship remained closely contested between leader Lewis Hamilton and Nico Rosberg, with the gap between them never larger than twenty-eight points after Hamilton's victory in round eleven in Belgium. The two would trade victories between rounds six and nine, closing the gap to as little as ten points. Sebastian Vettel, who at one time was within three points of the lead, after his victory in Malaysia, and who was the only non-Mercedes winner after eleven rounds, could not overcome team errors in Canada and Austria, and fell fifty-nine points off the pace of Hamilton after round nine. He rebounded in Hungary by winning his second race of the season, reducing the gap to Hamilton to forty-two points in the process, but fell out of a point-scoring position in Belgium after a tyre failure on the penultimate lap, dropping him to sixty-seven points behind the leader.


title: 2015 Formula One World Championship

text: Hamilton closed out the European portion of the season with his seventh victory of the season in Italy. With Rosberg's retirement at the event, Hamilton entered the closing rounds of the season with a lead of fifty-three points over his teammate in the Drivers' Championship standings, the largest gap of the season at that point, while Vettel sat a further twenty-one points behind. Hamilton's tenth pole position in Belgium assured him of victory in the FIA Pole Trophy, the award for the driver who achieves the most pole positions during the season. Mercedes had built up a 181-point lead over Ferrari in the Constructors' Championship, with Williams in third, 263 points behind the leaders. After twelve rounds, half of the teams had been represented on the podium, while nine out of ten had scored points.


title: 2015 Formula One World Championship

text: Shortly before the thirteenth round in Singapore, Manor Marussia announced that the American GP2 driver Alexander Rossi would race for the team, replacing Merhi in five of the final seven rounds, while Merhi was retained for the remaining two. Vettel won his third victory of the season in Singapore, closing his gap to Nico Rosberg in second place to just eight points.


title: 2015 Formula One World Championship

text: Rosberg could not close the gap to Hamilton in Japan or Russia; despite winning pole position in both races, his leads were short-lived. He was passed by Hamilton on the opening corner in Japan and retired on lap seven in Russia. Vettel capitalised on the results with third and second-place finishes respectively, to take second place in the Drivers' Championship from Rosberg with four rounds remaining, while Hamilton extended his lead to sixty-six points, the highest lead he had held in the season. A victory in the United States, with Rosberg and Vettel finishing second and third respectively, secured the third Drivers' Championship for Hamilton with three races left to run. Rosberg won the final three races in Mexico, Brazil, and Abu Dhabi to reclaim second in the Drivers' Championship from Vettel, while Hamilton secured the Fastest Lap Award in Brazil.


title: 2015 Formula One World Championship

text: Lewis Hamilton ended the season winning not only the championship, but also the FIA Pole Trophy for most pole positions of the season and the DHL Fastest Lap Award. Ferrari won the inaugural DHL Pit Stop Award, posting the fastest pit stop time at seven of the first eighteen races of the season. Both Hamilton and Mercedes collected their championship trophies at a gala held in Paris on 4 December 2015. Toro Rosso's Max Verstappen collected three post-season awards for Rookie of the Year, Personality of the Year and Action of the Year (for his overtake on Felipe Nasr through Blanchimont corner at the Belgian Grand Prix).


title: 2015 Formula One World Championship

text: Sauber's early season preparations were disrupted by a series of legal challenges from the former Caterham driver Giedo van der Garde, who claimed the team had reneged on a contract that was signed in June 2014. Van der Garde filed a motion with the Supreme Court of Victoria in Australia in an effort to force the team to replace one of their drivers with him at the opening round in Melbourne, with the court finding in his favour. Van der Garde later agreed not to participate in the event, with the driver and team settling the dispute for an undisclosed sum and terminating the contract following the first round.


title: 2015 Formula One World Championship

text: Lotus suffered financially throughout the season, culminating in Pirelli withholding their tyres for the Friday practice sessions in Hungary. Before the Belgian Grand Prix, amid negotiations with Renault for a potential takeover, the former Lotus reserve driver Charles Pic initiated legal action against Lotus alleging lack of seat time in 2014, resulting in breach of contract. Belgian authorities later moved to impound the assets of Lotus for four days following Grosjean's podium finish. After talks between the FIA and Lotus, the team was allowed to leave Spa with their equipment and cars, and was able to start the following race in Italy.


title: 2015 Formula One World Championship

text: Points were awarded to the top ten classified finishers in every race, using the following structure:


title: 2015 Formula One World Championship

text: In the event of a tie, a count-back system was used as a tie-breaker, with a driver's best result used to decide the standings.


title: 2015 Formula One World Championship

text: Constructors' Championship points were awarded as per the Drivers' Championship with the results of both cars taken into account. In the event of a tie, a count-back system was used as a tie-breaker, with a constructor's best result used to decide the standings.


title: Jon Ossoff

text: Thomas Jonathan Ossoff ( ; born February 16, 1987) is an American politician serving as the senior United States senator from Georgia since 2021. A member of the Democratic Party, Ossoff was previously a documentary filmmaker and investigative journalist.


title: Jon Ossoff

text: Born in Atlanta to a Jewish father and an Australian mother, Ossoff was the Democratic nominee in the 2017 special election for Georgia's 6th congressional district, which had long been considered a Republican stronghold. The special election proved competitive. It generated national attention, and became the most expensive House election in U.S. history. Ossoff narrowly lost the race to former Georgia Secretary of State Karen Handel.


title: Jon Ossoff

text: In 2020, Ossoff won the Democratic nomination for the 2020 U.S. Senate election in Georgia to run against then-incumbent Republican senator David Perdue. Neither candidate reached the 50 percent threshold on the November 3 general election, triggering a runoff election on January 5, 2021, which Ossoff won. Ossoff serves alongside fellow Democrat Raphael Warnock, who defeated incumbent Republican Kelly Loeffler in the 2020 Senate special election runoff, also on January 5, 2021. The two races attracted significant national attention and spending, as they decided which party would control the Senate in the 117th Congress. Warnock and Ossoff's victories helped the Democrats attain a 50–50 split in the Senate, which is an effective majority due to the tie-breaking vote of the Vice President. He took office on January 20, 2021, ultimately becoming the senior senator from Georgia.


title: Jon Ossoff

text: With his victory, Ossoff became the youngest member of the Senate elected since Don Nickles in 1980 as well as the first Jewish member of the Senate from Georgia, the first Jewish senator from the Deep South since Benjamin F. Jonas of Louisiana, who was elected in 1878, and the first millennial United States senator. Warnock and Ossoff are the first Democrats to represent Georgia in the United States Senate since Zell Miller in 2005.


title: Jon Ossoff

text: Ossoff was born on February 16, 1987, in Atlanta, Georgia. He was raised in Northlake, an unincorporated community. Ossoff's mother, Heather Fenton, is an Australian immigrant who was born and raised in Sydney and immigrated to the United States at the age of 23. She co-founded NewPower PAC, an organization that works to elect women to local office across Georgia. His father, Richard Ossoff, who is of Russian Jewish and Lithuanian Jewish descent, owns Strafford Publications, a specialist publishing company. Ossoff was raised Jewish and, due to his mother being a gentile, formally converted to the religion prior to his bar mitzvah. His ancestors fled pogroms in the early 20th century, and he noted in an interview that he grew up among Holocaust survivor relatives and detailed how this greatly influenced him and his worldviews. He previously held dual Australian citizenship through his mother.


title: Jon Ossoff

text: He attended The Paideia School, an independent school in Atlanta. While in high school, he interned for civil rights leader and U.S. representative John Lewis. In 2009, Ossoff graduated from Georgetown University's Walsh School of Foreign Service with a Bachelor of Science degree. He attended classes taught by former U.S. secretary of state Madeleine Albright and former Israeli ambassador to the United States Michael Oren. He earned a Master of Science degree in international political economy from the London School of Economics in 2013.


title: Jon Ossoff

text: After receiving a recommendation from John Lewis, Ossoff worked as a national security staffer and legislative assistant for foreign affairs and defense policy for U.S. representative Hank Johnson from 2007 to 2012. From 2013 to 2021, Ossoff was the managing director and chief executive officer of Insight: The World Investigates (TWI), a London-based investigative television production company that works with reporters to create documentaries about corruption in foreign countries. The firm produced BBC investigations about ISIS war crimes and death squads in East Africa. Ossoff was involved in producing a documentary about the staging of a play in Sierra Leone. Ossoff had previously received an inheritance of an unknown amount from his grandfather, a former co-owner of a Massachusetts leather factory, of which he used $250,000 to co-fund Insight: TWI alongside company founder and former BBC reporter Ron McCullagh, who first met Ossoff when he was 16-years-old during a family vacation to France and with whom he kept in contact afterward.


title: Jon Ossoff

text: After learning that Republican Tom Price of Georgia's 6th congressional district had been appointed secretary of health and human services by president-elect Donald Trump, Ossoff announced his candidacy for the special election on January 5, 2017. Ossoff quickly emerged as the most viable Democratic candidate out of a large field of candidates. He was endorsed by congressmen Hank Johnson and John Lewis, and state House Democratic leader Stacey Abrams. He also received public support from U.S. senator and Democratic presidential candidate Bernie Sanders. Ossoff raised over $8.3 million by early April of that year.


title: Jon Ossoff

text: According to "The Atlanta Journal-Constitution", Ossoff "transformed what was expected to be a quiet battle for a long-safe Republican seat into a proxy fight over Trump, the health care overhaul, and the partisan struggle for suburbia". When he entered the race, the Cook Partisan Voting Index rated Georgia's 6th congressional district at R+14; the district was not considered competitive, and had been represented in Congress by Republicans since 1978. Less than two months before Ossoff's announcement, Price had been re-elected in a landslide, with 62 percent of the vote.


title: Jon Ossoff

text: Ossoff grew up in what is now the 6th district, where his family still resides, although as of the election, he lived about outside the district's boundaries in the neighboring 4th district. He said he only lived in the 4th temporarily so that his girlfriend, now wife, who was then an Emory University medical student, could walk to work. Members of the House are required only to live in the state they represent. The two became engaged during the campaign.


title: Jon Ossoff

text: On April 18, 2017, no candidate received 50 percent of the vote in the blanket primary. Ossoff led with about 48.1 percent of the vote, Republican candidate Karen Handel received 19.8 percent, while the remainder of votes were scattered for 16 other candidates. Because no candidate secured an absolute majority, the two leading candidates, Ossoff and Handel, competed in a runoff election on June 20, 2017. Ossoff won all but 1 percent of the Democratic vote, while the Republican vote was more heavily split. Republicans collectively won 51.2 percent of the overall vote.


title: Jon Ossoff

text: Ossoff broke national fundraising records for a U.S. House candidate. In total, his campaign raised more than $23 million, two-thirds of which was contributed by small-dollar donors nationwide. His opponent, Handel, and national Republican groups attacked him for raising significant small-dollar contributions from outside of Georgia, although Handel's campaign received the bulk of its support from super PACs and other outside groups, including those funded anonymously by so-called "dark money". Combined spending by the campaigns and outside groups on their behalf added up to over $55 million, which was the most expensive House election in U.S. history. During the campaign, Republican strategy focused on connecting him to Democratic minority leader Nancy Pelosi, regarded as a polarising and unpopular figure by Republicans; Ossoff declined to say whether he would, if elected, support Pelosi for Speaker.


title: Jon Ossoff

text: In the June 20 runoff, Ossoff was defeated by Handel, 51.78 to 48.22 percent. According to "Atlanta Magazine", "while his percentage of the total vote remained steady from April to now, Ossoff garnered 32,220 more votes in those three months, a 34 percent increase ... Ossoff and his allies might have scooped up nearly every Democrat vote there was to get—and it still wasn't enough to overcome the GOP's numerical advantage." "The New York Times" reported that he "produced probably the strongest Democratic turnout in an off-year election in at least a decade", "brought a surprising number of irregular young and nonwhite voters to the polls," and nearly doubled youth turnout in the 6th district from the 2014 midterm election. However, according to "The Atlanta Journal-Constitution", "surging Democratic turnout wasn't enough to overcome heavy GOP voting in a district where Republicans far outnumber Democrats". Following reports of the election results, Frank Bruni, in an op-ed for "The New York Times", characterized the race as "demoralizing for Democrats". This was as close as a Democrat had come to winning this district since it assumed its current configuration as a northern suburban district in 1992; Democratic challengers had won more than 40 percent of the vote only twice before.


title: Jon Ossoff

text: On February 23, 2018, Ossoff announced he would not seek the seat in the regular election in 2018; the seat was won by Democrat Lucy McBath in November 2018.


title: Jon Ossoff

text: Ossoff ran in the Democratic primary election to unseat then-incumbent Republican senator David Perdue in the 2020 Senate election in Georgia. On June 10, Ossoff advanced to the general election by winning 53 percent of the vote. In July 2020, Perdue's campaign ran a Facebook advertisement in which Ossoff's nose was digitally altered to be larger, which Ossoff criticized as "one of the most classic anti-Semitic tropes". Perdue's campaign said that Perdue had not seen the image and that the widening and elongation of his nose was done by a vendor. The Perdue campaign pulled the advertisement.


title: Jon Ossoff

text: By October 2020, Ossoff raised over $100 million for his campaign, making him the best-funded Senate candidate in U.S. history.


title: Jon Ossoff

text: In the November 3 general election, Perdue received 2,462,617 votes (49.73%), while Ossoff received 2,374,519 votes (47.95%). Since no candidate received a majority of the vote on November 3, the top two finishers (Perdue and Ossoff) advanced to a January 5, 2021 runoff election.


title: Jon Ossoff

text: The closing argument of the Ossoff campaign focused on the $2,000 stimulus payments that he and Raphael Warnock would approve if they were to win their elections and give Democrats a majority in the Senate.


title: Jon Ossoff

text: Ossoff declared victory on the morning of January 6, 2021, and most major news outlets called the race for him later that day. While Perdue won more counties, Ossoff won overwhelmingly in the inner ring of the Atlanta metropolitan area. He won Cobb and Gwinnett counties, which have recently swung Democratic, by over 40,200 and 74,200 votes, respectively. The latter exceeded his statewide margin of about 55,000 votes. He ran slightly behind Warnock, who defeated Kelly Loeffler by 70,400 votes by also running up his margins in the Atlanta area. Perdue conceded the election on January 8.


title: Jon Ossoff

text: The vote was certified on January 19, which allowed the newly elected senators to take office the following day. On January 20, Ossoff was sworn into the Senate by the Vice President Kamala Harris.


title: Jon Ossoff

text: When Ossoff took office, he became the first Jewish senator from Georgia and the first Jewish senator elected from the Deep South since Benjamin F. Jonas of Louisiana in 1878, the first senator born in the 1980s, and, at 33, the youngest member of the chamber and the first millennial senator to be elected. He was sworn into office using the Bible of Rabbi Jacob Rothschild, the late rabbi of the Hebrew Benevolent Congregation Temple in Atlanta, which was bombed in 1958 by white supremacists for Rothschild’s civil rights activism. Ossoff had his Bar Mitzvah at the Temple.


title: Jon Ossoff

text: Ossoff is the first Democrat elected to a full term in the Senate from Georgia since Max Cleland in 1996. He and Warnock are the first Democratic U.S. senators from Georgia since Zell Miller left office in 2005. Ossoff assumed the role of senior U.S. senator from Georgia once he was sworn into office, making him the youngest senior senator since Robert M. La Follette Jr. and the most junior senior senator since Hiram Fong, who was 99th in seniority from Hawaii's admission until the end of the 86th Congress in 1961.


title: Jon Ossoff

text: On January20, 2021, Ossoff was sworn into the United States Senate in the 117th Congress by Vice President Kamala Harris.


title: Jon Ossoff

text: Ossoff supported all of President Joe Biden's cabinet nominees. He voted in favor of Avril Haines's nomination for director of national intelligence and General Lloyd Austin's nomination to serve as secretary of defense, as well as the required waiver for Austin to legally hold the position.


title: Jon Ossoff

text: On December 3, Ossoff petitioned Secretary of Education Miguel Cardona requesting Morris Brown College, a historically black college which Ossoff pledged to help during his campaign, regain their accreditation after having lost it in 2002 due to "years of financial issues and mismanagement." Accreditation would allow students of the college (50 at the time of the request) to be eligible for federal financial aid. The college's students were granted the ability to apply for federal financial aid by the Department of the Education one week later on December 10, 2021. After Ossoff’s petition in December 2021, The school regained accreditation in April 2022.


title: Jon Ossoff

text: In January 2022, Ossoff introduced legislation that would ban members of Congress and their spouses from trading stocks.


title: Jon Ossoff

text: According to "The New Yorker" in 2017, Ossoff has "progressive positions on women's issues and health care" and "moderate stances on jobs and security". Matthew Yglesias of "Vox" called his 2017 run for office an "Obama-style campaign", placing himself in the middle between progressive and conservative members within the Democratic Party. According to "The Washington Post", the 2017 Ossoff campaign opted not to turn the special election into a referendum on Trump's alleged scandals, but to focus on "policy decisions by the president and congressional Republicans". "The Atlanta Journal-Constitution" wrote that he "often tried to avoid nationalizing that campaign over fears of losing moderate voters". "The New York Times" observed that his 2017 campaign distanced itself from the national Democratic Party.


title: Jon Ossoff

text: In 2020, "The Atlanta Journal-Constitution" wrote that Ossoff was "more unapologetic about embracing liberal policy ideas than his Democratic predecessors during past statewide races. And where he once hesitated to hit Trump directly, he now pulls no punches as he seeks to tie Perdue to his White House ally."


title: Jon Ossoff

text: Ossoff supports abortion rights. He pledged to support only those judges who would uphold "Roe v. Wade", and he supports Planned Parenthood. In response to the June 2022 overturning of "Roe v. Wade", Ossoff stated that the Supreme Court "stripped American women of autonomy over their most personal health care decisions."


title: Jon Ossoff

text: On the issue of cannabis legalization, Ossoff says "It's past time to legalize, regulate, and tax cannabis – whose prohibition only enriches cartels, bail bondsmen, and the owners of private prisons." Ossoff says that as a member of the Senate he will push for "nationwide legalization" of cannabis, a substance that he says is "much less dangerous than alcohol".


title: Jon Ossoff

text: Ossoff opposes prison sentencing for nonviolent drug offenses. His website says, "Violent crime, murder, rape, human trafficking, and corruption are rampant, while we spend billions locking up nonviolent drug offenders."


title: Jon Ossoff

text: Ossoff opposes both defunding the police, as well as abolishing the U.S. Immigration and Customs Enforcement. He supports task forces to fight organized crime and political corruption, and he wants to establish national standards for the use of force by police. Ossoff has advocated for demilitarizing the police and banning private prisons.


title: Jon Ossoff

text: Ossoff supports reinstating Glass-Steagall, and he supports ending speculative trading. He has supported stimulus spending in the wave of the COVID-19 pandemic. Ossoff supported an additional round of stimulus checks of $1,200 in late 2020. Ossoff supports increasing economic relief for businesses and households affected by COVID-19 pandemic, and believes testing, treatment, and vaccines for COVID-19 should be free. Ossoff voted in favor of the American Rescue Plan Act of 2021, an economic stimulus bill aimed at speeding up the United States' recovery from the economic and health effects of the COVID-19 pandemic and the ongoing recession.


title: Jon Ossoff

text: He supports funding infrastructure. He supports financial regulation to restrict unfair practices by overseas competitors.


title: Jon Ossoff

text: His campaign promised to prioritize making education more affordable, while making trade school, vocational training, public colleges free, and supports debt forgiveness.


title: Jon Ossoff

text: He accepts the Scientific opinion on climate change, and has said that "climate change is a threat to our security and prosperity". He supports U.S. participation in the Paris Agreement. He is not in favor of the Green New Deal. Ossoff is pro GHG restrictions, and in 2017, he advocated investigations into failures to enforce environmental laws. He supports protection of endangered species and habitats, and he criticized the Trump administration's rollbacks of environmental standards.


title: Jon Ossoff

text: In 2022, U.S. Senator Jon Ossoff blocked a proposed titanium mine in the Okefenoke Swamp after the U.S. Fish and Wildlife Service warned of severe potential damage to the wildlife refuge. The mine was proposed by Twin Pines Minerals LLC in 2018.


title: Jon Ossoff

text: Ossoff supports renewable energy. He believes human driven climate change is responsible for global warming, and supports investing in clean energy.


title: Jon Ossoff

text: Ossoff resisted criticizing President Joe Biden for the withdrawal of troops from Afghanistan in August 2021, as other Democratic politicians had at the time, instead stating he was focused on "supporting the State Department and the Department of Defense as they work with limited time to expedite the evacuation" of stranded Americans and American-allied Afghans. Ossoff would condemn the subsequent airport attack in Kabul, which killed 13 American military personnel, stating: "I condemn this cowardly and despicable terrorist attack."


title: Jon Ossoff

text: Ossoff led a group of 25 Democratic senators who called for an immediate ceasefire in a joint statement during the 2021 Israel–Palestine crisis. The statement said: "Israel has the right to defend itself from Hamas' rocket attacks, in a manner proportionate with the threat its citizens are facing." Ossoff has stated Israel's situation holds high importance to him due to him having Orthodox relatives in the country, saying he wishes for "a future where all people in the region live in peace, live in prosperity and have equal rights."


title: Jon Ossoff

text: Ossoff has called for the repeal of "wasteful, anti-competitive special interest subsidies that make it hard for entrepreneurs to raise capital, enter the market, create jobs, and compete with larger firms who have lobbyists in Washington". He has said the government funds "$16 billion in duplicate programs. That can be cut," an assertion that PolitiFact rated "Mostly True". Ossoff refused to accept donations from PACs.


title: Jon Ossoff

text: Ossoff supports statehood for the District of Columbia and for Puerto Rico. He is open to term limits for federal judges, and he voted to pass the John R. Lewis Voting Rights Advancement Act and the Freedom to Vote Act in 2022. He opposes the decision in Citizens United v. FEC.


title: Jon Ossoff

text: Ossoff has supported various gun control measures, including background checks, red flag laws, and an assault weapons ban. He was endorsed by Everytown for Gun Safety.


title: Jon Ossoff

text: Ossoff supports the Affordable Care Act (also known as Obamacare). His health care policy includes three principles: "One, no American should suffer or die from preventable or treatable illness. Two, no one should go broke because they get sick. And three, no business should go under or lay off employees because it can't keep up with health insurance premiums." He does not support pushing for a single-payer health care system, such as Medicare for All. He opposed both the March 2017 and May 2017 versions of the American Health Care Act, the House Republican bill that would have repealed the Affordable Care Act. He said that the May 2017 version was worse than the earlier one "because it does even less to protect those with pre-existing conditions". He supports improving and redesigning the ACA.


title: Jon Ossoff

text: Ossoff told "The Atlanta Journal-Constitution" that he supported tax credits for small businesses related to health care. He supports Medicaid and Medicare funding, and he wants to empower Medicare to negotiate lower drug prices while expanding Medicaid and investing in new public health clinics. He supports a public option over a single-payer healthcare system.


title: Jon Ossoff

text: Ossoff supports comprehensive immigration reform that would both strengthen enforcement along the Mexican border and provide a path to citizenship for some undocumented immigrants. He opposes Trump's border wall, but he maintains his support for strengthening borders while providing a path for DREAMers.


title: Jon Ossoff

text: Ossoff describes his support for the LGBT community as "unwavering". He also supports the Equality Act, which would prohibit discrimination on the basis of sex, gender identity, and sexual orientation.


title: Jon Ossoff

text: Ossoff supports taxing to balance the budget, and he has advocated for undoing Trump-era tax cuts. He wants to reduce the tax burden for small businesses and simplify family living by lowering taxes on all but the wealthiest Americans. He opposes an increase in current federal income tax rates.


title: Jon Ossoff

text: Ossoff has been sharply critical of President Donald Trump, criticizing what he calls Trump's "divisive approach to government", in addition to his COVID policies, and saying: "I have great respect for the office. I don't have great personal admiration for the man himself." After Trump sent out a tweet the day before Ossoff's primary on April 19, 2017, calling him a "super Liberal Democrat" who wanted to "protect criminals, allow illegal immigration and raise taxes," Ossoff dismissed Trump's claims and called him "misinformed". FactCheck.org found that Trump's claim was a distortion, and that there was no evidence that Ossoff had ever advocated for any broad-based tax hikes. Nevertheless, Ossoff said that he would be willing to work with Trump on issues of mutual interest, such as infrastructure spending. After Trump's disclosure of classified information to Russia, Ossoff said of impeachment that "I don't think we're there." He called for "a full and transparent and independent assessment of what level of interference there was by Russian intelligence services in the U.S. election. And overseers in Congress and any independent counsel or commission to do so should follow those facts wherever they lead."


title: Jon Ossoff

text: Ossoff voted to convict Trump during his second impeachment on the charge of incitement of insurrection following the 2021 United States Capitol attack, joining all Democrats and seven Republicans.


title: Jon Ossoff

text: Following passage of Georgia's controversial Election Integrity Act of 2021, signed into law by Republican Governor Brian Kemp and passed by the Republican-led state legislature, several businesses from the Major League Baseball organization to the production of Will Smith film "Emancipation" boycotted the state in protest. In an interview with CNN, Ossoff expressed his displeasure with the bill, while also saying he didn't support the corporate boycotts, stating Georgians "rely upon and hope for and welcome jobs, investment and opportunity."


title: Jon Ossoff

text: Ossoff has been described as able to effectively appeal to young people by using TikTok, the social media app most popular with Generation Z. On the night he was elected to the Senate, Ossoff's posts on Twitter from the previous decade have attracted renewed attention on social media, including several references to "Star Wars", the musical group Imagine Dragons, and anime. He is described as the "first Extremely Online senator".


title: Jon Ossoff

text: In January 2021, "Vogue" reported on an "adoring" Instagram account of self-declared "simps" expressing affection toward Ossoff. After Ossoff’s election, in July 2021, "The Daily Beast" reported on an “Ossimp Patrol” on Twitter that monitors “Ossoff simps” on the platform, and replies to their tweets with an ActBlue link prompting to donate to Senator Raphael Warnock’s 2022 reelection campaign, and get out the vote organizations in Georgia and Texas. When shown this by "The Daily Beast", Ossoff is said to have "paused for a moment" and "furrowed his brow" before saying he wasn't aware of any of this, but did commend the "great community" he had that supported him during his 2020-21 senate campaign.


title: Jon Ossoff

text: Ossoff is married to Alisha Kramer, an obstetrics and gynecology resident at Emory University, and a graduate of Georgetown University and Emory University School of Medicine. Ossoff married Kramer in 2017 after 12 years of dating. On the night of Ossoff's election to the United States Senate in January 2021, Kramer was working an overnight shift in Emory University Hospital in Atlanta. They have one daughter, born in December 2021.


title: Lichen

text: A lichen ( , ) is a composite organism that arises from algae or cyanobacteria living among filaments of multiple fungi species in a mutualistic relationship. Lichens have properties different from those of their component organisms. They come in many colors, sizes, and forms and are sometimes plant-like, but are not plants. They may have tiny, leafless branches (fruticose); flat leaf-like structures (foliose); grow crust-like, adhering tightly to a surface (substrate) like a thick coat of paint (crustose); have a powder-like appearance (leprose); or other growth forms.


title: Lichen

text: A "macrolichen" is a lichen that is either bush-like or leafy; all other lichens are termed "microlichens". Here, "macro" and "micro" do not refer to size, but to the growth form. Common names for lichens may contain the word "moss" (e.g., "reindeer moss", "Iceland moss"), and lichens may superficially look like and grow with mosses, but they are not closely related to mosses or any plant. Lichens do not have roots that absorb water and nutrients as plants do, but like plants, they produce their own nutrition by photosynthesis. When they grow on plants, they do not live as parasites, but instead use the plant's surface as a substrate.


title: Lichen

text: Lichens occur from sea level to high alpine elevations, in many environmental conditions, and can grow on almost any surface. They are abundant growing on bark, leaves, mosses, or other lichens and hanging from branches "living on thin air" (epiphytes) in rainforests and in temperate woodland. They grow on rock, walls, gravestones, roofs, exposed soil surfaces, rubber, bones, and in the soil as part of biological soil crusts. Various lichens have adapted to survive in some of the most extreme environments on Earth: arctic tundra, hot dry deserts, rocky coasts, and toxic slag heaps. They can even live inside solid rock, growing between the grains.


title: Lichen

text: It is estimated that 6–8% of Earth's land surface is covered by lichens. There are about 20,000 known species. Some lichens have lost the ability to reproduce sexually, yet continue to speciate. They can be seen as being relatively self-contained miniature ecosystems, where the fungi, algae, or cyanobacteria have the potential to engage with other microorganisms in a functioning system that may evolve as an even more complex composite organism. Lichens may be long-lived, with some considered to be among the oldest living things. They are among the first living things to grow on fresh rock exposed after an event such as a landslide. The long life-span and slow and regular growth rate of some species can be used to date events (lichenometry).


title: Lichen

text: The English word "lichen" derives from the Greek ("tree moss, lichen, lichen-like eruption on skin") via Latin . The Greek noun, which literally means "licker", derives from the verb , "to lick". In American English, "lichen" is pronounced the same as the verb "liken" (). In British English, both this pronunciation and one rhyming with "kitchen" () are used.


title: Lichen

text: Lichens grow in a wide range of shapes and forms (morphologies). The shape of a lichen is usually determined by the organization of the fungal filaments. The nonreproductive tissues, or vegetative body parts, are called the "thallus". Lichens are grouped by thallus type, since the thallus is usually the most visually prominent part of the lichen. Thallus growth forms typically correspond to a few basic internal structure types. Common names for lichens often come from a growth form or color that is typical of a lichen genus.


title: Lichen

text: There are variations in growth types in a single lichen species, grey areas between the growth type descriptions, and overlapping between growth types, so some authors might describe lichens using different growth type descriptions.


title: Lichen

text: When a crustose lichen gets old, the center may start to crack up like old-dried paint, old-broken asphalt paving, or like the polygonal "islands" of cracked-up mud in a dried lakebed. This is called being rimose or areolate, and the "island" pieces separated by the cracks are called areolas. The areolas appear separated, but are (or were) connected by an underlying prothallus or hypothallus. When a crustose lichen grows from a center and appears to radiate out, it is called crustose placodioid. When the edges of the areolas lift up from the substrate, it is called squamulose.


title: Lichen

text: These growth form groups are not precisely defined. Foliose lichens may sometimes branch and appear to be fruticose. Fruticose lichens may have flattened branching parts and appear leafy. Squamulose lichens may appear where the edges lift up. Gelatinous lichens may appear leafy when dry. Means of telling them apart in these cases are in the sections below.


title: Lichen

text: Structures involved in reproduction often appear as discs, bumps, or squiggly lines on the surface of the thallus. The thallus is not always the part of the lichen that is most visually noticeable. Some lichens can grow "inside" solid rock between the grains (endolithic lichens), with only the sexual fruiting part visible growing outside the rock. These may be dramatic in color or appearance. Forms of these sexual parts are not in the above growth form categories. The most visually noticeable reproductive parts are often circular, raised, plate-like or disc-like outgrowths, with crinkly edges, and are described in sections below.


title: Lichen

text: Lichens come in many colors. Coloration is usually determined by the photosynthetic component. Special pigments, such as yellow usnic acid, give lichens a variety of colors, including reds, oranges, yellows, and browns, especially in exposed, dry habitats. In the absence of special pigments, lichens are usually bright green to olive gray when wet, gray or grayish-green to brown when dry. This is because moisture causes the surface skin (cortex) to become more transparent, exposing the green photobiont layer. Different colored lichens covering large areas of exposed rock surfaces, or lichens covering or hanging from bark can be a spectacular display when the patches of diverse colors "come to life" or "glow" in brilliant displays following rain.


title: Lichen

text: Different colored lichens may inhabit different adjacent sections of a rock face, depending on the angle of exposure to light. Colonies of lichens may be spectacular in appearance, dominating much of the surface of the visual landscape in forests and natural places, such as the vertical "paint" covering the vast rock faces of Yosemite National Park.


title: Lichen

text: Color is used in identification. The color of a lichen changes depending on whether the lichen is wet or dry. Color descriptions used for identification are based on the color that shows when the lichen is dry. Dry lichens with a cyanobacterium as the photosynthetic partner tend to be dark grey, brown, or black.


title: Lichen

text: The underside of the leaf-like lobes of foliose lichens is a different color from the top side (dorsiventral), often brown or black, sometimes white. A fruticose lichen may have flattened "branches", appearing similar to a foliose lichen, but the underside of a leaf-like structure on a fruticose lichen is the "same" color as the top side. The leaf-like lobes of a foliose lichen may branch, giving the appearance of a fruticose lichen, but the underside will be a "different" color from the top side.


title: Lichen

text: A lichen consists of a simple photosynthesizing organism, usually a green alga or cyanobacterium, surrounded by filaments of a fungus. Generally, most of a lichen's bulk is made of interwoven fungal filaments, but this is reversed in filamentous and gelatinous lichens. The fungus is called a "mycobiont". The photosynthesizing organism is called a "photobiont". Algal photobionts are called "phycobionts". Cyanobacteria photobionts are called "cyanobionts".


title: Lichen

text: The part of a lichen that is not involved in reproduction, the "body" or "vegetative tissue" of a lichen, is called the "thallus". The thallus form is very different from any form where the fungus or alga are growing separately. The thallus is made up of filaments of the fungus called "hyphae". The filaments grow by branching then rejoining to create a mesh, which is called being "anastomosed". The mesh of fungal filaments may be dense or loose.


title: Lichen

text: Generally, the fungal mesh surrounds the algal or cyanobacterial cells, often enclosing them within complex fungal tissues that are unique to lichen associations. The thallus may or may not have a protective "skin" of densely packed fungal filaments, often containing a second fungal species, which is called a "cortex." Fruticose lichens have one cortex layer wrapping around the "branches". Foliose lichens have an upper cortex on the top side of the "leaf", and a separate lower cortex on the bottom side. Crustose and squamulose lichens have only an upper cortex, with the "inside" of the lichen in direct contact with the surface they grow on (the "substrate"). Even if the edges peel up from the substrate and appear flat and leaf-like, they lack a lower cortex, unlike foliose lichens. Filamentous, byssoid, leprose, gelatinous, and other lichens do not have a cortex, which is called being ecorticate.


title: Lichen

text: Fruticose, foliose, crustose, and squamulose lichens generally have up to three different types of tissue, differentiated by having different densities of fungal filaments. The top layer, where the lichen contacts the environment, is called a "cortex". The cortex is made of densely tightly woven, packed, and glued together (agglutinated) fungal filaments. The dense packing makes the cortex act like a protective "skin", keeping other organisms out, and reducing the intensity of sunlight on the layers below. The cortex layer can be up to several hundred micrometers (μm) in thickness (less than a millimeter). The cortex may be further topped by an epicortex of secretions, not cells, 0.6–1 μm thick in some lichens. This secretion layer may or may not have pores.


title: Lichen

text: Below the cortex layer is a layer called the "photobiontic layer" or "symbiont layer". The symbiont layer has less densely packed fungal filaments, with the photosynthetic partner embedded in them. The less dense packing allows air circulation during photosynthesis, similar to the anatomy of a leaf. Each cell or group of cells of the photobiont is usually individually wrapped by hyphae, and in some cases penetrated by a haustorium. In crustose and foliose lichens, algae in the photobiontic layer are diffuse among the fungal filaments, decreasing in gradation into the layer below. In fruticose lichens, the photobiontic layer is sharply distinct from the layer below.


title: Lichen

text: The layer beneath the symbiont layer called is called the "medulla". The medulla is less densely packed with fungal filaments than the layers above. In foliose lichens, there is usually, as in "Peltigera", another densely packed layer of fungal filaments called the lower cortex. Root-like fungal structures called "rhizines" (usually) grow from the lower cortex to attach or anchor the lichen to the substrate. Fruticose lichens have a single cortex wrapping all the way around the "stems" and "branches". The medulla is the lowest layer, and may form a cottony white inner core for the branchlike thallus, or it may be hollow. Crustose and squamulose lichens lack a lower cortex, and the medulla is in direct contact with the substrate that the lichen grows on.


title: Lichen

text: In crustose areolate lichens, the edges of the areolas peel up from the substrate and appear leafy. In squamulose lichens the part of the lichen thallus that is not attached to the substrate may also appear leafy. But these leafy parts lack a lower cortex, which distinguishes crustose and squamulose lichens from foliose lichens. Conversely, foliose lichens may appear flattened against the substrate like a crustose lichen, but most of the leaf-like lobes can be lifted up from the substrate because it is separated from it by a tightly packed lower cortex.


title: Lichen

text: Gelatinous, byssoid, and leprose lichens lack a cortex (are ecorticate), and generally have only undifferentiated tissue, similar to only having a symbiont layer.


title: Lichen

text: In lichens that include both green algal "and" cyanobacterial symbionts, the cyanobacteria may be held on the upper or lower surface in small pustules called "cephalodia".


title: Lichen

text: "Pruinia" is a whitish coating on top of an upper surface. An "epinecral layer" is "a layer of horny dead fungal hyphae with indistinct lumina in or near the cortex above the algal layer".


title: Lichen

text: In August 2016, it was reported that some macrolichens have more than one species of fungus in their tissues.


title: Lichen

text: A lichen is a composite organism that emerges from algae or cyanobacteria living among the filaments (hyphae) of the fungi in a mutually beneficial symbiotic relationship. The fungi benefit from the carbohydrates produced by the algae or cyanobacteria via photosynthesis. The algae or cyanobacteria benefit by being protected from the environment by the filaments of the fungi, which also gather moisture and nutrients from the environment, and (usually) provide an anchor to it. Although some photosynthetic partners in a lichen can survive outside the lichen, the lichen symbiotic association extends the ecological range of both partners, whereby most descriptions of lichen associations describe them as symbiotic. Both partners gain water and mineral nutrients mainly from the atmosphere, through rain and dust. The fungal partner protects the alga by retaining water, serving as a larger capture area for mineral nutrients and, in some cases, provides minerals obtained from the substrate. If a cyanobacterium is present, as a primary partner or another symbiont in addition to a green alga as in certain tripartite lichens, they can fix atmospheric nitrogen, complementing the activities of the green alga.


title: Lichen

text: In three different lineages the fungal partner has independently lost the mitochondrial gene atp9, which has key functions in mitochondrial energy production. The loss makes the fungi completely dependent on their symbionts.


title: Lichen

text: The algal or cyanobacterial cells are photosynthetic and, as in plants, they reduce atmospheric carbon dioxide into organic carbon sugars to feed both symbionts. Phycobionts (algae) produce sugar alcohols (ribitol, sorbitol, and erythritol), which are absorbed by the mycobiont (fungus). Cyanobionts produce glucose. Lichenized fungal cells can make the photobiont "leak" out the products of photosynthesis, where they can then be absorbed by the fungus.


title: Lichen

text: It appears many, probably the majority, of lichen also live in a symbiotic relationship with an order of basidiomycete yeasts called Cyphobasidiales. The absence of this third partner could explain why growing lichen in the laboratory is difficult. The yeast cells are responsible for the formation of the characteristic cortex of the lichen thallus, and could also be important for its shape.


title: Lichen

text: The lichen combination of alga or cyanobacterium with a fungus has a very different form (morphology), physiology, and biochemistry than the component fungus, alga, or cyanobacterium growing by itself, naturally or in culture. The body (thallus) of most lichens is different from those of either the fungus or alga growing separately. When grown in the laboratory in the absence of its photobiont, a lichen fungus develops as a structureless, undifferentiated mass of fungal filaments (hyphae). If combined with its photobiont under appropriate conditions, its characteristic form associated with the photobiont emerges, in the process called morphogenesis. In a few remarkable cases, a single lichen fungus can develop into two very different lichen forms when associating with either a green algal or a cyanobacterial symbiont. Quite naturally, these alternative forms were at first considered to be different species, until they were found growing in a conjoined manner.


title: Lichen

text: Evidence that lichens are examples of successful symbiosis is the fact that lichens can be found in almost every habitat and geographic area on the planet. Two species in two genera of green algae are found in over 35% of all lichens, but can only rarely be found living on their own outside of a lichen.


title: Lichen

text: In a case where one fungal partner simultaneously had two green algae partners that outperform each other in different climates, this might indicate having more than one photosynthetic partner at the same time might enable the lichen to exist in a wider range of habitats and geographic locations.


title: Lichen

text: At least one form of lichen, the North American beard-like lichens, are constituted of not two but three symbiotic partners: an ascomycetous fungus, a photosynthetic alga, and, unexpectedly, a basidiomycetous yeast.


title: Lichen

text: Phycobionts can have a net output of sugars with only water vapor. The thallus must be saturated with liquid water for cyanobionts to photosynthesize.


title: Lichen

text: Algae produce sugars that are absorbed by the fungus by diffusion into special fungal hyphae called appressoria or haustoria in contact with the wall of the algal cells. The appressoria or haustoria may produce a substance that increases permeability of the algal cell walls, and may penetrate the walls. The algae may contribute up to 80% of their sugar production to the fungus.


title: Lichen

text: Lichen associations may be examples of mutualism or commensalism, but the lichen relationship can be considered parasitic under circumstances where the photosynthetic partner can exist in nature independently of the fungal partner, but not vice versa. Photobiont cells are routinely destroyed in the course of nutrient exchange. The association continues because reproduction of the photobiont cells matches the rate at which they are destroyed. The fungus surrounds the algal cells, often enclosing them within complex fungal tissues unique to lichen associations. In many species the fungus penetrates the algal cell wall, forming penetration pegs (haustoria) similar to those produced by pathogenic fungi that feed on a host. Cyanobacteria in laboratory settings can grow faster when they are alone rather than when they are part of a lichen.


title: Lichen

text: Symbiosis in lichens is so well-balanced that lichens have been considered to be relatively self-contained miniature ecosystems in and of themselves. It is thought that lichens may be even more complex symbiotic systems that include non-photosynthetic bacterial communities performing other functions as partners in a holobiont.


title: Lichen

text: Many lichens are very sensitive to environmental disturbances and can be used to cheaply assess air pollution, ozone depletion, and metal contamination. Lichens have been used in making dyes, perfumes, and in traditional medicines. A few lichen species are eaten by insects or larger animals, such as reindeer. Lichens are widely used as environmental indicators or bio-indicators. When air is very badly polluted with sulphur dioxide, there may be no lichens present; only some green algae can tolerate those conditions. If the air is clean, then shrubby, hairy and leafy lichens become abundant. A few lichen species can tolerate fairly high levels of pollution, and are commonly found in urban areas, on pavements, walls and tree bark. The most sensitive lichens are shrubby and leafy, while the most tolerant lichens are all crusty in appearance. Since industrialisation, many of the shrubby and leafy lichens such as "Ramalina", "Usnea" and "Lobaria" species have very limited ranges, often being confined to the areas which have the cleanest air.


title: Lichen

text: Some fungi can only be found living "on" lichens as obligate parasites. These are referred to as lichenicolous fungi, and are a different species from the fungus living inside the lichen; thus they are not considered to be part of the lichen.


title: Lichen

text: Moisture makes the cortex become more transparent. This way, the algae can conduct photosynthesis when moisture is available, and is protected at other times. When the cortex is more transparent, the algae show more clearly and the lichen looks greener.


title: Lichen

text: Lichens can show intense antioxidant activity. Secondary metabolites are often deposited as crystals in the apoplast. Secondary metabolites are thought to play a role in preference for some substrates over others.


title: Lichen

text: Sometimes lichens contain structures made from fungal metabolites, for example crustose lichens sometimes have a polysaccharide layer in the cortex.


title: Lichen

text: In crustose lichens, the area along the margin is where the most active growth is taking place. Most crustose lichens grow only 1–2 mm in diameter per year.


title: Lichen

text: Lichens may be long-lived, with some considered to be among the oldest living organisms. Lifespan is difficult to measure because what defines the "same" individual lichen is not precise. Lichens grow by vegetatively breaking off a piece, which may or may not be defined as the "same" lichen, and two lichens can merge, then becoming the "same" lichen. An Arctic species called "map lichen" ("Rhizocarpon geographicum") has been dated at 8,600 years, apparently the world's oldest living organism.


title: Lichen

text: Unlike simple dehydration in plants and animals, lichens may experience a "complete" loss of body water in dry periods. Lichens are capable of surviving extremely low levels of water content (poikilohydric). They quickly absorb water when it becomes available again, becoming soft and fleshy.


title: Lichen

text: In tests, lichen survived and showed remarkable results on the adaptation capacity of photosynthetic activity within the simulation time of 34 days under Martian conditions in the Mars Simulation Laboratory (MSL) maintained by the German Aerospace Center (DLR).


title: Lichen

text: The European Space Agency has discovered that lichens can survive unprotected in space. In an experiment led by Leopoldo Sancho from the Complutense University of Madrid, two species of lichen—"Rhizocarpon geographicum" and "Xanthoria elegans"—were sealed in a capsule and launched on a Russian Soyuz rocket 31 May 2005. Once in orbit, the capsules were opened and the lichens were directly exposed to the vacuum of space with its widely fluctuating temperatures and cosmic radiation. After 15 days, the lichens were brought back to earth and were found to be unchanged in their ability to photosynthesize.


title: Lichen

text: Many lichens reproduce asexually, either by a piece breaking off and growing on its own (vegetative reproduction) or through the dispersal of diaspores containing a few algal cells surrounded by fungal cells. Because of the relative lack of differentiation in the thallus, the line between diaspore formation and vegetative reproduction is often blurred. Fruticose lichens can easily fragment, and new lichens can grow from the fragment (vegetative reproduction). Many lichens break up into fragments when they dry, dispersing themselves by wind action, to resume growth when moisture returns. "Soredia" (singular: "soredium") are small groups of algal cells surrounded by fungal filaments that form in structures called soralia, from which the soredia can be dispersed by wind. "Isidia" (singular: "isidium") are branched, spiny, elongated, outgrowths from the thallus that break off for mechanical dispersal. Lichen propagules (diaspores) typically contain cells from both partners, although the fungal components of so-called "fringe species" rely instead on algal cells dispersed by the "core species".


title: Lichen

text: Structures involved in reproduction often appear as discs, bumps, or squiggly lines on the surface of the thallus. Though it has been argued that sexual reproduction in photobionts is selected against, there is strong evidence that suggests meiotic activities (sexual reproduction) in "Trebouxia". Many lichen fungi reproduce sexually like other fungi, producing spores formed by meiosis and fusion of gametes. Following dispersal, such fungal spores must meet with a compatible algal partner before a functional lichen can form.


title: Lichen

text: Some lichen fungi belong to the phylum Basidiomycota ("basidiolichens") and produce mushroom-like reproductive structures resembling those of their nonlichenized relatives.


title: Lichen

text: Most lichen fungi belong to Ascomycetes ("ascolichens"). Among the ascolichens, spores are produced in spore-producing structures called "ascomata". The most common types of ascomata are the "apothecium" (plural: apothecia) and "perithecium" (plural: perithecia). Apothecia are usually cups or plate-like discs located on the top surface of the lichen thallus. When apothecia are shaped like squiggly line segments instead of like discs, they are called "lirellae". Perithecia are shaped like flasks that are immersed in the lichen thallus tissue, which has a small hole for the spores to escape the flask, and appear like black dots on the lichen surface.


title: Lichen

text: The three most common spore body types are raised discs called "apothecia" (singular: apothecium), bottle-like cups with a small hole at the top called "perithecia" (singular: perithecium), and "pycnidia" (singular: pycnidium), shaped like perithecia but without asci (an ascus is the structure that contains and releases the sexual spores in fungi of the Ascomycota).


title: Lichen

text: The apothecium has a layer of exposed spore-producing cells called "asci" (singular: ascus), and is usually a different color from the thallus tissue. When the apothecium has an outer margin, the margin is called the "exciple". When the exciple has a color similar to colored thallus tissue the apothecium or lichen is called "lecanorine", meaning similar to members of the genus "Lecanora". When the exciple is blackened like carbon it is called "lecideine" meaning similar to members of the genus "Lecidea". When the margin is pale or colorless it is called "biatorine".


title: Lichen

text: A "podetium" (plural: podetia) is a lichenized stalk-like structure of the fruiting body rising from the thallus, associated with some fungi that produce a fungal apothecium. Since it is part of the reproductive tissue, podetia are not considered part of the main body (thallus), but may be visually prominent. The podetium may be branched, and sometimes cup-like. They usually bear the fungal pycnidia or apothecia or both. Many lichens have apothecia that are visible to the naked eye.


title: Lichen

text: Most lichens produce abundant sexual structures. Many species appear to disperse only by sexual spores. For example, the crustose lichens "Graphis scripta" and "Ochrolechia parella" produce no symbiotic vegetative propagules. Instead, the lichen-forming fungi of these species reproduce sexually by self-fertilization (i.e. they are homothallic). This breeding system may enable successful reproduction in harsh environments.


title: Lichen

text: "Mazaedia" (singular: mazaedium) are apothecia shaped like a dressmaker's pin in pin lichens, where the fruiting body is a brown or black mass of loose ascospores enclosed by a cup-shaped exciple, which sits on top of a tiny stalk.


title: Lichen

text: Lichens are classified by the fungal component. Lichen species are given the same scientific name (binomial name) as the fungus species in the lichen. Lichens are being integrated into the classification schemes for fungi. The alga bears its own scientific name, which bears no relationship to that of the lichen or fungus. There are about 13,500–17,000 identified lichen species. Nearly 20% of known fungal species are associated with lichens.


title: Lichen

text: ""Lichenized fungus"" may refer to the entire lichen, or to just the fungus. This may cause confusion without context. A particular fungus species may form lichens with different algae species, giving rise to what appear to be different lichen species, but which are still classified (as of 2014) as the same lichen species.


title: Lichen

text: Formerly, some lichen taxonomists placed lichens in their own division, the "Mycophycophyta", but this practice is no longer accepted because the components belong to separate lineages. Neither the ascolichens nor the basidiolichens form monophyletic lineages in their respective fungal phyla, but they do form several major solely or primarily lichen-forming groups within each phylum. Even more unusual than basidiolichens is the fungus "Geosiphon pyriforme", a member of the Glomeromycota that is unique in that it encloses a cyanobacterial symbiont inside its cells. "Geosiphon" is not usually considered to be a lichen, and its peculiar symbiosis was not recognized for many years. The genus is more closely allied to endomycorrhizal genera. Fungi from Verrucariales also form marine lichens with the brown algae "Petroderma maculiforme", and have a symbiotic relationship with seaweed (such as rockweed) and "Blidingia minima", where the algae are the dominant components. The fungi is thought to help the rockweeds to resist desiccation when exposed to air. In addition, lichens can also use yellow-green algae ("Heterococcus") as their symbiotic partner.


title: Lichen

text: Lichens independently emerged from fungi associating with algae and cyanobacteria multiple times throughout history.


title: Lichen

text: The fungal component of a lichen is called the "mycobiont". The mycobiont may be an Ascomycete or Basidiomycete. The associated lichens are called either ascolichens or basidiolichens, respectively. Living as a symbiont in a lichen appears to be a successful way for a fungus to derive essential nutrients, since about 20% of all fungal species have acquired this mode of life.


title: Lichen

text: Thalli produced by a given fungal symbiont with its differing partners may be similar, and the secondary metabolites identical, indicating that the fungus has the dominant role in determining the morphology of the lichen. But the same mycobiont with different photobionts may also produce very different growth forms. Lichens are known in which there is one fungus associated with two or even three algal species.


title: Lichen

text: Although each lichen thallus generally appears homogeneous, some evidence seems to suggest that the fungal component may consist of more than one genetic individual of that species.


title: Lichen

text: The photosynthetic partner in a lichen is called a "photobiont". The photobionts in lichens come from a variety of simple prokaryotic and eukaryotic organisms. In the majority of lichens the photobiont is a green alga (Chlorophyta) or a cyanobacterium. In some lichens both types are present; in such cases, the alga is typically the primary partner, with the cyanobacteria being located in cryptic pockets. Algal photobionts are called "phycobionts", while cyanobacterial photobionts are called "cyanobionts". According to one source, about 90% of all known lichens have phycobionts, and about 10% have cyanobionts, while another source states that two thirds of lichens have green algae as phycobiont, and about one third have a cyanobiont. Approximately 100 species of photosynthetic partners from 40 genera and five distinct classes (prokaryotic: Cyanophyceae; eukaryotic: Trebouxiophyceae, Phaeophyceae, Chlorophyceae) have been found to associate with the lichen-forming fungi.


title: Lichen

text: Common algal photobionts are from the genera "Trebouxia", "Trentepohlia", "Pseudotrebouxia", or "Myrmecia". "Trebouxia" is the most common genus of green algae in lichens, occurring in about 40% of all lichens. "Trebouxioid" means either a photobiont that is in the genus "Trebouxia", or resembles a member of that genus, and is therefore presumably a member of the class Trebouxiophyceae. The second most commonly represented green alga genus is "Trentepohlia". Overall, about 100 species of eukaryotes are known to occur as photobionts in lichens. All the algae are probably able to exist independently in nature as well as in the lichen.


title: Lichen

text: A "cyanolichen" is a lichen with a cyanobacterium as its main photosynthetic component (photobiont). Most cyanolichen are also ascolichens, but a few basidiolichen like Dictyonema and Acantholichen have cyanobacteria as their partner.


title: Lichen

text: The most commonly occurring cyanobacterium genus is "Nostoc". Other common cyanobacterium photobionts are from "Scytonema". Many cyanolichens are small and black, and have limestone as the substrate. Another cyanolichen group, the jelly lichens of the genera "Collema" or "Leptogium" are gelatinous and live on moist soils. Another group of large and foliose species including "Peltigera", "Lobaria", and "Degelia" are grey-blue, especially when dampened or wet. Many of these characterize the Lobarion communities of higher rainfall areas in western Britain, e.g., in the Celtic rain forest. Strains of cyanobacteria found in various cyanolichens are often closely related to one another. They differ from the most closely related free-living strains.


title: Lichen

text: The lichen association is a close symbiosis. It extends the ecological range of both partners but is not always obligatory for their growth and reproduction in natural environments, since many of the algal symbionts can live independently. A prominent example is the alga "Trentepohlia", which forms orange-coloured populations on tree trunks and suitable rock faces. Lichen propagules (diaspores) typically contain cells from both partners, although the fungal components of so-called "fringe species" rely instead on algal cells dispersed by the "core species".


title: Lichen

text: The same cyanobiont species can occur in association with different fungal species as lichen partners. The same phycobiont species can occur in association with different fungal species as lichen partners. More than one phycobiont may be present in a single thallus.


title: Lichen

text: A single lichen may contain several algal genotypes. These multiple genotypes may better enable response to adaptation to environmental changes, and enable the lichen to inhabit a wider range of environments.


title: Lichen

text: There are about 20,000 known lichen species. But what is meant by "species" is different from what is meant by biological species in plants, animals, or fungi, where being the same species implies that there is a common ancestral lineage. Because lichens are combinations of members of two or even three different biological kingdoms, these components "must" have a "different" ancestral lineage from each other. By convention, lichens are still called "species" anyway, and are classified according to the species of their fungus, not the species of the algae or cyanobacteria. Lichens are given the same scientific name (binomial name) as the fungus in them, which may cause some confusion. The alga bears its own scientific name, which has no relationship to the name of the lichen or fungus.


title: Lichen

text: Depending on context, "lichenized fungus" may refer to the entire lichen, or to the fungus when it is in the lichen, which can be grown in culture in isolation from the algae or cyanobacteria. Some algae and cyanobacteria are found naturally living outside of the lichen. The fungal, algal, or cyanobacterial component of a lichen can be grown by itself in culture. When growing by themselves, the fungus, algae, or cyanobacteria have very different properties than those of the lichen. Lichen properties such as growth form, physiology, and biochemistry, are very different from the combination of the properties of the fungus and the algae or cyanobacteria.


title: Lichen

text: The same fungus growing in combination with different algae or cyanobacteria, can produce lichens that are very different in most properties, meeting non-DNA criteria for being different "species". Historically, these different combinations were classified as different species. When the fungus is identified as being the same using modern DNA methods, these apparently different species get reclassified as the "same" species under the current (2014) convention for classification by fungal component. This has led to debate about this classification convention. These apparently different "species" have their own independent evolutionary history.


title: Lichen

text: There is also debate as to the appropriateness of giving the same binomial name to the fungus, and to the lichen that combines that fungus with an alga or cyanobacterium (synecdoche). This is especially the case when combining the same fungus with different algae or cyanobacteria produces dramatically different lichen organisms, which would be considered different species by any measure other than the DNA of the fungal component. If the whole lichen produced by the same fungus growing in association with different algae or cyanobacteria, were to be classified as different "species", the number of "lichen species" would be greater.


title: Lichen

text: The largest number of lichenized fungi occur in the Ascomycota, with about 40% of species forming such an association. Some of these lichenized fungi occur in orders with nonlichenized fungi that live as saprotrophs or plant parasites (for example, the Leotiales, Dothideales, and Pezizales). Other lichen fungi occur in only five orders in which all members are engaged in this habit (Orders Graphidales, Gyalectales, Peltigerales, Pertusariales, and Teloschistales). Overall, about 98% of lichens have an ascomycetous mycobiont. Next to the Ascomycota, the largest number of lichenized fungi occur in the unassigned fungi imperfecti, a catch-all category for fungi whose sexual form of reproduction has never been observed. Comparatively few basidiomycetes are lichenized, but these include agarics, such as species of "Lichenomphalia", clavarioid fungi, such as species of "Multiclavula", and corticioid fungi, such as species of "Dictyonema".


title: Lichen

text: The outcome of the "Pd test" is called "Pd", which is also used as an abbreviation for the chemical used in the test, para-phenylenediamine. If putting a drop on a lichen turns an area bright yellow to orange, this helps identify it as belonging to either the genus "Cladonia" or "Lecanora".


title: Lichen

text: The fossil record for lichens is poor. The extreme habitats that lichens dominate, such as tundra, mountains, and deserts, are not ordinarily conducive to producing fossils. There are fossilized lichens embedded in amber. The fossilized "Anzia" is found in pieces of amber in northern Europe and dates back approximately 40 million years. Lichen fragments are also found in fossil leaf beds, such as "Lobaria" from Trinity County in northern California, USA, dating back to the early to middle Miocene.


title: Lichen

text: The oldest fossil lichen in which both symbiotic partners have been recovered is "Winfrenatia", an early zygomycetous (Glomeromycotan) lichen symbiosis that may have involved controlled parasitism, is permineralized in the Rhynie Chert of Scotland, dating from early Early Devonian, about 400 million years ago. The slightly older fossil "Spongiophyton" has also been interpreted as a lichen on morphological and isotopic grounds, although the isotopic basis is decidedly shaky. It has been demonstrated that Silurian-Devonian fossils "Nematothallus" and "Prototaxites" were lichenized. Thus lichenized Ascomycota and Basidiomycota were a component of Early Silurian-Devonian terrestrial ecosystems. Newer research suggests that lichen evolved after the evolution of land plants.


title: Lichen

text: The ancestral ecological state of both Ascomycota and Basidiomycota was probably saprobism, and independent lichenization events may have occurred multiple times. In 1995, Gargas and colleagues proposed that there were at least five independent origins of lichenization; three in the basidiomycetes and at least two in the Ascomycetes. Lutzoni et al. (2001) suggest lichenization probably evolved earlier and was followed by multiple independent losses. Some non-lichen-forming fungi may have secondarily lost the ability to form a lichen association. As a result, lichenization has been viewed as a highly successful nutritional strategy.


title: Lichen

text: Lichenized Glomeromycota may extend well back into the Precambrian. Lichen-like fossils consisting of coccoid cells (cyanobacteria?) and thin filaments (mucoromycotinan Glomeromycota?) are permineralized in marine phosphorite of the Doushantuo Formation in southern China. These fossils are thought to be 551 to 635 million years old or Ediacaran. Ediacaran acritarchs also have many similarities with Glomeromycotan vesicles and spores. It has also been claimed that Ediacaran fossils including "Dickinsonia", were lichens, although this claim is controversial. Endosymbiotic Glomeromycota comparable with living "Geosiphon" may extend back into the Proterozoic in the form of 1500 million year old "Horodyskia" and 2200 million year old "Diskagma". Discovery of these fossils suggest that fungi developed symbiotic partnerships with photoautotrophs long before the evolution of vascular plants, though the Ediacaran lichen hypothesis is largely rejected due to an inappropriate definition of lichens based on taphonomy and substrate ecology. However, a 2019 study by the same scientist who rejected the Ediacaran lichen hypothesis, Nelsen, used new time-calibrated phylogenies to conclude that there is no evidence of lichen before the existence of vascular plants.


title: Lichen

text: Lecanoromycetes, one of the most common classes of lichen-forming fungi, diverged from its ancestor, which may have also been lichen forming, around 258 million years ago, during the late Paleozoic period. However, the closely related clade Euritiomycetes appears to have become lichen-forming only 52 million years ago, during the early Cenozoic period.


title: Lichen

text: Lichens cover about 7% of the planet's surface and grow on and in a wide range of substrates and habitats, including some of the most extreme conditions on earth. They are abundant growing on bark, leaves, and hanging from epiphyte branches in rain forests and in temperate woodland. They grow on bare rock, walls, gravestones, roofs, and exposed soil surfaces. They can survive in some of the most extreme environments on Earth: arctic tundra, hot dry deserts, rocky coasts, and toxic slag heaps. They can live inside solid rock, growing between the grains, and in the soil as part of a biological soil crust in arid habitats such as deserts. Some lichens do not grow on anything, living out their lives blowing about the environment.


title: Lichen

text: When growing on mineral surfaces, some lichens slowly decompose their substrate by chemically degrading and physically disrupting the minerals, contributing to the process of weathering by which rocks are gradually turned into soil. While this contribution to weathering is usually benign, it can cause problems for artificial stone structures. For example, there is an ongoing lichen growth problem on Mount Rushmore National Memorial that requires the employment of mountain-climbing conservators to clean the monument.


title: Lichen

text: Lichens are not parasites on the plants they grow on, but only use them as a substrate. The fungi of some lichen species may "take over" the algae of other lichen species. Lichens make their own food from their photosynthetic parts and by absorbing minerals from the environment. Lichens growing on leaves may have the appearance of being parasites on the leaves, but they are not. Some lichens in "Diploschistes" parasitise other lichens. "Diploschistes muscorum" starts its development in the tissue of a host "Cladonia" species.


title: Lichen

text: In the arctic tundra, lichens, together with mosses and liverworts, make up the majority of the ground cover, which helps insulate the ground and may provide forage for grazing animals. An example is "Reindeer moss", which is a lichen, not a moss.


title: Lichen

text: There are only two species of known permanently submerged lichens; "Hydrothyria venosa" is found in fresh water environments, and "Verrucaria serpuloides" is found in marine environments.


title: Lichen

text: A crustose lichen that grows on rock is called a "saxicolous lichen". Crustose lichens that grow on the rock are epilithic, and those that grow immersed inside rock, growing between the crystals with only their fruiting bodies exposed to the air, are called "endolithic lichens". A crustose lichen that grows on bark is called a "corticolous lichen". A lichen that grows on wood from which the bark has been stripped is called a "lignicolous lichen". Lichens that grow immersed inside plant tissues are called "endophloidic lichens" or "endophloidal lichens". Lichens that use leaves as substrates, whether the leaf is still on the tree or on the ground, are called "epiphyllous" or "foliicolous". A "terricolous lichen" grows on the soil as a substrate. Many squamulous lichens are terricolous. "Umbilicate lichens" are foliose lichens that are attached to the substrate at only one point. A "vagrant lichen" is not attached to a substrate at all, and lives its life being blown around by the wind.


title: Lichen

text: In addition to distinct physical mechanisms by which lichens break down raw stone, recent studies indicate lichens attack stone chemically, entering newly chelated minerals into the ecology.The lichen exudates, which have powerful chelating capacity, the widespread occurrence of mineral neoformation, particularly metal oxalates, together with the characteristics of weathered substrates, all confirm the significance of lichens as chemical weathering agents.Over time, this activity creates new fertile soil from lifeless stone.


title: Lichen

text: Lichens may be important in contributing nitrogen to soils in some deserts through being eaten, along with their rock substrate, by snails, which then defecate, putting the nitrogen into the soils. Lichens help bind and stabilize soil sand in dunes. In deserts and semi-arid areas, lichens are part of extensive, living biological soil crusts, essential for maintaining the soil structure. Lichens have a long fossil record in soils dating back 2.2 billion years.


title: Lichen

text: Lichens are pioneer species, among the first living things to grow on bare rock or areas denuded of life by a disaster. Lichens may have to compete with plants for access to sunlight, but because of their small size and slow growth, they thrive in places where higher plants have difficulty growing. Lichens are often the first to settle in places lacking soil, constituting the sole vegetation in some extreme environments such as those found at high mountain elevations and at high latitudes. Some survive in the tough conditions of deserts, and others on frozen soil of the Arctic regions.


title: Lichen

text: A major ecophysiological advantage of lichens is that they are poikilohydric ("poikilo"- variable, "hydric"- relating to water), meaning that though they have little control over the status of their hydration, they can tolerate irregular and extended periods of severe desiccation. Like some mosses, liverworts, ferns and a few resurrection plants, upon desiccation, lichens enter a metabolic suspension or stasis (known as cryptobiosis) in which the cells of the lichen symbionts are dehydrated to a degree that halts most biochemical activity. In this cryptobiotic state, lichens can survive wider extremes of temperature, radiation and drought in the harsh environments they often inhabit.


title: Lichen

text: Lichens do not have roots and do not need to tap continuous reservoirs of water like most higher plants, thus they can grow in locations impossible for most plants, such as bare rock, sterile soil or sand, and various artificial structures such as walls, roofs, and monuments. Many lichens also grow as epiphytes ("epi"- on the surface, "phyte"- plant) on plants, particularly on the trunks and branches of trees. When growing on plants, lichens are not parasites; they do not consume any part of the plant nor poison it. Lichens produce allelopathic chemicals that inhibit the growth of mosses. Some ground-dwelling lichens, such as members of the subgenus "Cladina" (reindeer lichens), produce allelopathic chemicals that leach into the soil and inhibit the germination of seeds, spruce and other plants. Stability (that is, longevity) of their substrate is a major factor of lichen habitats. Most lichens grow on stable rock surfaces or the bark of old trees, but many others grow on soil and sand. In these latter cases, lichens are often an important part of soil stabilization; indeed, in some desert ecosystems, vascular (higher) plant seeds cannot become established except in places where lichen crusts stabilize the sand and help retain water.


title: Lichen

text: Lichens may be eaten by some animals, such as reindeer, living in arctic regions. The larvae of a number of Lepidoptera species feed exclusively on lichens. These include common footman and marbled beauty. They are very low in protein and high in carbohydrates, making them unsuitable for some animals. The Northern flying squirrel uses it for nesting, food and winter water.


title: Lichen

text: If lichens are exposed to air pollutants at all times, without any deciduous parts, they are unable to avoid the accumulation of pollutants. Also lacking stomata and a cuticle, lichens may absorb aerosols and gases over the entire thallus surface from which they may readily diffuse to the photobiont layer. Because lichens do not possess roots, their primary source of most elements is the air, and therefore elemental levels in lichens often reflect the accumulated composition of ambient air. The processes by which atmospheric deposition occurs include fog and dew, gaseous absorption, and dry deposition. Consequently, many environmental studies with lichens emphasize their feasibility as effective biomonitors of atmospheric quality.


title: Lichen

text: Not all lichens are equally sensitive to air pollutants, so different lichen species show different levels of sensitivity to specific atmospheric pollutants. The sensitivity of a lichen to air pollution is directly related to the energy needs of the mycobiont, so that the stronger the dependency of the mycobiont on the photobiont, the more sensitive the lichen is to air pollution. Upon exposure to air pollution, the photobiont may use metabolic energy for repair of its cellular structures that would otherwise be used for maintenance of its photosynthetic activity, therefore leaving less metabolic energy available for the mycobiont. The alteration of the balance between the photobiont and mycobiont can lead to the breakdown of the symbiotic association. Therefore, lichen decline may result not only from the accumulation of toxic substances, but also from altered nutrient supplies that favor one symbiont over the other.


title: Lichen

text: This interaction between lichens and air pollution has been used as a means of monitoring air quality since 1859, with more systematic methods developed by William Nylander in 1866.


title: Lichen

text: Lichens are eaten by many different cultures across the world. Although some lichens are only eaten in times of famine, others are a staple food or even a delicacy. Two obstacles are often encountered when eating lichens: lichen polysaccharides are generally indigestible to humans, and lichens usually contain mildly toxic secondary compounds that should be removed before eating. Very few lichens are poisonous, but those high in vulpinic acid or usnic acid are toxic. Most poisonous lichens are yellow.


title: Lichen

text: In the past, Iceland moss ("Cetraria islandica") was an important source of food for humans in northern Europe, and was cooked as a bread, porridge, pudding, soup, or salad. "Bryoria fremontii" (edible horsehair lichen) was an important food in parts of North America, where it was usually pitcooked. Northern peoples in North America and Siberia traditionally eat the partially digested reindeer lichen ("Cladina" spp.) after they remove it from the rumen of caribou or reindeer that have been killed. Rock tripe ("Umbilicaria" spp. and "Lasalia" spp.) is a lichen that has frequently been used as an emergency food in North America, and one species, "Umbilicaria esculenta", ("iwatake" in Japanese) is used in a variety of traditional Korean and Japanese foods.


title: Lichen

text: Lichenometry is a technique used to determine the age of exposed rock surfaces based on the size of lichen thalli. Introduced by Beschel in the 1950s, the technique has found many applications. it is used in archaeology, palaeontology, and geomorphology. It uses the presumed regular but slow rate of lichen growth to determine the age of exposed rock. Measuring the diameter (or other size measurement) of the largest lichen of a species on a rock surface indicates the length of time since the rock surface was first exposed. Lichen can be preserved on old rock faces for up to 10,000 years, providing the maximum age limit of the technique, though it is most accurate (within 10% error) when applied to surfaces that have been exposed for less than 1,000 years. Lichenometry is especially useful for dating surfaces less than 500 years old, as radiocarbon dating techniques are less accurate over this period. The lichens most commonly used for lichenometry are those of the genera "Rhizocarpon" (e.g. the species "Rhizocarpon geographicum", map lichen) and "Xanthoria".


title: Lichen

text: Lichens have been shown to degrade polyester resins, as can be seen in archaeological sites in the Roman city of Baelo Claudia in Spain. Lichens can accumulate several environmental pollutants such as lead, copper, and radionuclides. Some species of lichen, such as "Parmelia sulcata" (called a hammered shield lichen, among other names) and "Lobaria pulmonaria" (lung lichen), and many in the "Cladonia" genus, have been shown to produce serine proteases capable of the degradation of pathogenic forms of prion protein (PrP), which may be useful in treating contaminated environmental reservoirs.


title: Lichen

text: Many lichens produce secondary compounds, including pigments that reduce harmful amounts of sunlight and powerful toxins that deter herbivores or kill bacteria. These compounds are very useful for lichen identification, and have had economic importance as dyes such as cudbear or primitive antibiotics.


title: Lichen

text: A pH indicator (which can indicate acidic or basic substances) called litmus is a dye extracted from the lichen "Roccella tinctoria" ("dyer's weed") by boiling. It gives its name to the well-known litmus test.


title: Lichen

text: Traditional dyes of the Scottish Highlands for Harris tweed and other traditional cloths were made from lichens, including the orange "Xanthoria parietina" ("common orange lichen") and the grey foliaceous "Parmelia saxatilis" common on rocks and known colloquially as "crottle".


title: Lichen

text: There are reports dating almost 2,000 years old of lichens being used to make purple and red dyes. Of great historical and commercial significance are lichens belonging to the family "Roccellaceae", commonly called orchella weed or orchil. Orcein and other lichen dyes have largely been replaced by synthetic versions.


title: Lichen

text: Historically, in traditional medicine of Europe, "Lobaria pulmonaria" was collected in large quantities as "lungwort", due to its lung-like appearance (the "doctrine of signatures" suggesting that herbs can treat body parts that they physically resemble). Similarly, "Peltigera leucophlebia" ("ruffled freckled pelt") was used as a supposed cure for thrush, due to the resemblance of its cephalodia to the appearance of the disease.


title: Lichen

text: Lichens produce metabolites being researched for their potential therapeutic or diagnostic value. Some metabolites produced by lichens are structurally and functionally similar to broad-spectrum antibiotics while few are associated respectively to antiseptic similarities. Usnic acid is the most commonly studied metabolite produced by lichens. It is also under research as a bactericidal agent against "Escherichia coli" and "Staphylococcus aureus".


title: Lichen

text: Colonies of lichens may be spectacular in appearance, dominating the surface of the visual landscape as part of the aesthetic appeal to visitors of Yosemite National Park, Sequoia National Park, and the Bay of Fires. Orange and yellow lichens add to the ambience of desert trees, tundras, and rocky seashores. Intricate webs of lichens hanging from tree branches add a mysterious aspect to forests. Fruticose lichens are used in model railroading and other modeling hobbies as a material for making miniature trees and shrubs.


title: Lichen

text: In early Midrashic literature, the Hebrew word ""vayilafeth"" in Ruth 3:8 is explained as referring to Ruth entwining herself around Boaz like lichen. The 10th century Arab physician, Al-Tamimi, mentions lichens dissolved in vinegar and rose water being used in his day for the treatment of skin diseases and rashes.


title: Lichen

text: The plot of John Wyndham's science fiction novel "Trouble with Lichen" revolves around an anti-aging chemical extracted from a lichen.


title: Lichen

text: Although lichens had been recognized as organisms for quite some time, it was not until 1867, when Swiss botanist Simon Schwendener proposed his dual theory of lichens, that lichens are a combination of fungi with algae or cyanobacteria, whereby the true nature of the lichen association began to emerge. Schwendener's hypothesis, which at the time lacked experimental evidence, arose from his extensive analysis of the anatomy and development in lichens, algae, and fungi using a light microscope. Many of the leading lichenologists at the time, such as James Crombie and Nylander, rejected Schwendener's hypothesis because the common consensus was that all living organisms were autonomous.


title: Lichen

text: Other prominent biologists, such as Heinrich Anton de Bary, Albert Bernhard Frank, Beatrix Potter, Melchior Treub and Hermann Hellriegel were not so quick to reject Schwendener's ideas and the concept soon spread into other areas of study, such as microbial, plant, animal and human pathogens. When the complex relationships between pathogenic microorganisms and their hosts were finally identified, Schwendener's hypothesis began to gain popularity. Further experimental proof of the dual nature of lichens was obtained when Eugen Thomas published his results in 1939 on the first successful re-synthesis experiment.


title: Lichen

text: In the 2010s, a new facet of the fungi-algae partnership was discovered. Toby Spribille and colleagues found that many types of lichen that were long thought to be ascomycete-algae pairs were actually ascomycete-basidiomycete-algae trios.


title: Kempegowda International Airport

text: Kempegowda International Airport is an international airport serving Bangalore, the capital of Karnataka, India. Spread over , it is located about north of the city near the suburb of Devanahalli. It is owned and operated by Bengaluru International Airport Limited (BIAL), a public–private consortium. The airport opened in May 2008 as an alternative to increased congestion at HAL Airport, the original primary commercial airport serving the city. It is named after Kempe Gowda I, the founder of Bangalore. Kempegowda International Airport became Karnataka's first fully solar powered airport developed by CleanMax Solar.