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Tuesday, September 27, 2022

Hashtag activism

From Wikipedia, the free encyclopedia

Hashtag activism refers to the use of Twitter's hashtags for Internet activism. The Hashtag, has become one of the many ways that social media contributes to civic engagement and social movements. The use of the hashtag on social media provides users with an opportunity to share information and opinions about social issues in a way that others (followers) can interact and engage as part of a larger conversation with the potential to create change. The hashtag itself consists of a word or phrase that is connected to a social or political issue, and fosters a place where discourse can occur. Social Media, provides an important platform for historically marginalized populations. Through the use of hashtags these groups are able to communicate, mobilize, and advocate for issues less visible to the mainstream.

Supporters of the power of hashtag activism believe that it allows users to connect with individuals from all over the world and share information quickly. Critics, on the other hand, doubt that hashtag activism leads to real change, as users are simply indicating that they care enough to post a hashtag, rather than taking practical action to make a difference.

History

The Hashtag, as it is currently used across social media sites was first proposed on Twitter by former Google developer Chris Messina, in 2007. The purpose of the invention was to create a meta tag that allowed users to track dynamic content in relation to a particular event or topic. Twitter's initial response to the use of the hashtag for such purposes was negative. The social media site posted that "these things were for nerds" but later that year saw the impact with use of the #sandiegofire which allowed users to track content related to the fire, the safety of loved ones, and general updates. The use of the hashtag has now spread to other social media sites including Facebook, Instagram, and Tik Tok. Since 2007, the hashtag has been used to coordinate conversations online, find supporters, and arrange protests allowing for users to be active participate in social and political movements.

Notable examples

The following notable examples are organized by categories: human rights, awareness, political, and trends.

Race

#BlackLivesMatter

The Black Lives Matter movement calls for an end to police brutality and the killings of African-Americans in the U.S. The #BlackLivesMatter hashtag was first started by Alicia Garza, Patrisse Cullors, and Opal Tometi as a response to the trial and later acquittal of George Zimmerman who shot and killed 17-year-old Trayvon Martin. The hashtag saw a revival in 2014, after the shooting of Michael Brown in Ferguson, Missouri, and after a grand jury did not indict police officer Daniel Pantaleo in the death of Eric Garner.

#IStandWithAhmed

Barack Obama profile picture.jpg
President Obama Twitter Verified Badge.svg Twitter
@POTUS44

Cool clock, Ahmed. Want to bring it to the White House? We should inspire more kids like you to like science. It's what makes America great.

September 16, 2015

IstandwithAhmed: In 2015, a teenage student named Ahmed Mohamed was arrested at his high school in Irving, Texas after his teacher mistook his reassembled clock for a bomb. Ultimately, he was not convicted of any crimes, but he was suspended from school. Shortly after his story hit the news, a tech blogger named Anil Dash tweeted a picture of Ahmed being arrested in his NASA T-shirt along with the "#IstandwithAhmed." His tweet went viral and drew accusations of racism and Islamophobia against the school. It sparked an online movement where many individuals, including scientists and engineers, tweeted their support for Ahmed under the same hashtag.

#TakeAKnee

#TakeAknee has been a movement since 2016 and was created with the intention of calling attention to the police brutality and racial inequality taking place in America. This movement was enacted primarily by NFL athletes, most notably Colin Kaepernick, through kneeling for the duration of the national anthem; this act has stirred significant controversy because it is interpreted by nationalists as being a disrespectful act that insults the American flag, veterans, and the values the flag represents. This movement ultimately led to #BoycottNFL and controversy that resulted in the NFL ban requiring players to stand for the national anthem, or stay in the locker room. #TakeAKnee is often known as “the U.S. National Anthem Protest”, and is often compared to protests during the civil rights era, lending to a chain of protests led by athletes in different sports. While the police brutality being faced by African Americans was being protested, white American athletes were also seen taking a knee. As a whole, the #TakeAKnee movement created controversy questioning the legal and constitutional rights of individuals and their ability to protest the U.S. National Anthem.

#MyAsianAmericanStory

In August 2015, " a 15-year-old high student named Jason Fong created #MyAsianAmericanStory to highlight immigration stories of Asian Americans after presidential candidate Jeb Bush made a remark about Asian people and their "anchor babies." Fong stated that he started the hashtag to show that "Asian-Americans are part of the American narrative." Users of the tag tweeted about their diverse family immigration histories and encounters with racism. Fong said he was inspired to start #MyAsianAmericanStory in part by hashtags such as #BlackLivesMatter and participated in other hashtag campaigns such as #Asians4BlackLives in order to show his support for dismantling “a broken system that protects police misconduct.”

#thisis2016

In October 2016, following an anti-Asian incident in New York City and the subsequent open letter to the victim from Michael Luo, The New York Times released a video entitled "#thisis2016: Asian-Americans Respond". The video featured Asian Americans who had experienced racism. #thisis2016 subsequently emerged as a hashtag to highlight racism Asian Americans faced. Eventually, #BrownAsiansExist came to prominence following an open letter written to The New York Times expressing their disappointment in the lack of South and Southeast Asian Americans in their "#thisis2016" video. #BrownAsiansExist more broadly highlights the erasure of South Asian and Southeast Asian Americans in the American media's portrayal of Asian Americans.

#OscarsSoWhite

#OscarSoWhite is a hashtag campaign started by BroadwayBlack.com managing editor April Reign and was sparked by the Oscars nominees in 2016. All of the 20 actors nominated for lead and supporting actor categories were white, despite multiple films that year starring African American leads that had received critics' prizes and guild awards. The campaign sparked a conversation about diversity, representation, and racism in the film industry. The movement is connected to causing enough external pressure to significantly change the racial composition of Academy membership. Following the peak of the hashtag's popularity, the Academy instated 41% minority voters and 46% female voters. Production companies felt the pressure as well, and subsequently diversified their casting and staffing decisions as well, hiring Ava Duvernay, an African-American female director, to head the production of A Wrinkle in Time and hiring non-white actors in the traditionally white Star Wars series.

#PublishingPaidMe

Women's rights

#YesAllWomen

YesAllWomen is a Twitter hashtag and social media campaign in which users share examples or stories of misogyny and violence against women. #YesAllWomen was created in reaction to another hashtag #NotAllMen, to express that all women are affected by sexism and harassment, even though not all men are sexist. The hashtag quickly became used by women throughout social media to share their experiences of misogyny and sexism. The hashtag was popular in May 2014 surrounding discussions of the 2014 Isla Vista killings.

#ShoutYourAbortion

#ShoutYourAbortion is a hashtag and social media campaign used on Twitter that encourages women who have experience with abortion to break the silence surrounding it. The hashtag was created by American writer Lindy West and friends Amelia Bonow and Kimberly Morrison in response to the US House of Representatives efforts to defund Planned Parenthood following the Planned Parenthood 2015 undercover videos controversy.

#ilooklikeanengineer

In August 2015, the #ilooklikeanengineer campaign started. The movement was started by Isis Anchalee to promote discussion of gender issues. Anchalee created the hashtag in response to backlash regarding her face being featured in an ad campaign for the company she works for. One year after the creation of #ilooklikeanengineer 250,000 people had used the hashtag.

#MeToo

#MeToo is a Twitter hashtag that raises awareness about sexual assault by encouraging survivors to share their stories. The hashtag was initially first used in 2007 by Tarana Burke but was later popularized and brought to the attention of the media on October 15, 2017, when Alyssa Milano, using Twitter, encouraged individuals to speak up about their experience with assault and say 'Me Too'. Initially meant to simply raise awareness but has developed into a movement and as of October 2018, the hashtag has been used 19 million times. The movement has sparked many other movements like #HowIWillChange and has also led to certain punishments towards the perpetrators. As a reaction, the #HimToo hashtag was created. It that refers to the social media campaign for false rape allegation.

#MosqueMeToo

In February 2018, the Mosque Me Too movement started, following the Me Too movement which gained worldwide prominence in October 2017 and the following months. Muslim women started sharing their experiences of sexual abuse at Muslim holy sites and on pilgrimages such as Hajj, Mecca, Saudi Arabia, using the hashtag #MosqueMeToo.

#WomensMarch

On January 21, 2017, an estimated 2.6 million individuals marched around the world in response to the rhetoric of newly elected President Donald Trump. The march was organized primarily online through Facebook. Now occurring annually, the goal of the Women's March is to raise awareness and advocates for human rights through peaceful protest.

Similar to other hashtag movements, #WomensMarch has an online presence. The movement has a Facebook page that is active, verified under the name Women's March, that was created on November 20, 2016. As of April 2, 2019 the page is liked by over 800,000 individuals and has a following of more than 850,000 users. Outside of the official page, there are multiple pages defined by geographic region including but not limited to Women's March on Connecticut, Women's March on San Diego, and Women's March Milan. In addition to Facebook, the Women's March Movement has an active profile on Instagram and as of April 2019 the page has 1.2 million followers.

#EleNão

Protester in Porto Alegre, Brazil, participating in the Ele Não movement.

On September 19, 2018, the Ele Não movement ("Ele Não" is Portuguese for "not him"), also known as the protests against Jair Bolsonaro, were demonstrations led by women which took place in several regions of Brazil and the world. The main goal was to protest against Bolsonaro and his presidential campaign and his sexist declarations.

#WhereisPengShuai

After the November 2021 disappearance of Chinese Tennis athlete, Peng Shuai, the hashtag #WhereisPengShuai appeared on Twitter and was Tweeted by athletes such as Serena Williams and Naomi Osaka.

Other examples

A 2012 Twitter discussion among women working in games, collated under the hashtag #1reasonwhy, indicated that sexist practices such as the oversexualization of female video game characters, workplace harassment and unequal pay for men and women were common in the games industry.

The hashtag #NotYourAsianSidekick was initiated by Suey Park and Juliet Shen in December 2013 on Twitter. Suey Park is a freelance writer who is most known for her Twitter campaign to cancel the Colbert Show, while Juliet Shen ran a blog on Asian American feminism. They started the hashtag town hall as a way to create a platform for structured conversation around misogyny and issues specific to Asian American women. In less than 24 hours, #NotYourAsianSidekick had been used over 45,000 times.

DeafTalent is a hashtag used to highlight through social media the capabilities of the deaf and hard of hearing community. Prior to the hashtag's emergence, in the creative industry, hearing actors had been cast in deaf roles. The SAGE Deaf Studies Encyclopedia wrote, "In response to this, the social media hashtags #DeafTalent and #POCDeafTalent were created. The hashtags, while originally used to point out problematic portrayals of deaf characters and sign language in the media, are now also used to celebrate the wide breadth and multiplicity of deaf actors, artists, and other talent in the world."

The hashtag, #Boymom, has taken to social media platforms in order to display the so-called "chaotic" and "messy" experiences mothers of boys go through. Instagram appears to be the platform with the most #Boymom hashtags, with nearly 12.9 million hashtags. Interestingly, #Girlmom falls significantly behind in numbers with only 4.8 million. Currently, there is much speculation surrounding this hashtag. People argue that it creates an environment for children where they feel unable to fully express their gender. Some people even go as far as to say that it perpetuates the sexist idea that sons are valued more than daughters.

Awareness

#Kony2012

A Kony 2012 poster

Kony 2012 is a short film produced by Invisible Children, Inc. (authors of Invisible Children). It was released on March 5, 2012.

The film's purpose was to promote the charity's "Stop Kony" movement to make African cult and militia leader, indicted war criminal and the International Criminal Court fugitive Joseph Kony globally known in order to have him arrested by the end of 2012, when the campaign expired. The film spread virally through the #Kony2012 hashtag.

#WhyIStayed

In 2014, a media release of security camera footage that appeared to show NFL player, Ray Rice, punching his then-fiancée, Janay Rice, sparked public conversation on why victims of abuse stay in abusive relationships. In response to this question, writer and domestic abuse survivor Beverly Gooden started the #WhyIStayed campaign via Twitter in an effort to "change the tone of the conversation". The hashtag began to trend nationally five hours after its creation and was used more than 46,000 times that day. Beverly appeared on NPR's All Things Considered to discuss hashtag activism.

#BringBackOurGirls

First Lady Michelle Obama initiated the #BringBackOurGirls hashtag.
 

Boko Haram kidnapped over 200 schoolgirls from Chibok, Nigeria in May 2014, refusing to return the girls. The hashtag #BringBackOurGirls was created and used in hopes of keeping the story in the news and bringing international attention to it. The hashtag was first used by a corporate lawyer named Ibrahim Abdullahi, and has also been used by the likes of First Lady Michelle Obama, who used it to raise awareness for the kidnapped girls. The hashtag in itself has received 2 million retweets.

#AmINext

In the Fall of 2014, a Canadian Inuit woman named Holly Jarrett created the #AmINext hashtag campaign to raise awareness about the Canadian Government's lack of response to the high rate of violence against Indigenous women. The campaign involves people taking photos of themselves with signs holding "#AmINext" and posting it to social media. The campaign was meant to encourage a national conversation about the invisibility and vulnerability of the female Indigenous demographic and call attention to the minimal efforts of the Government in investigating the murders and disappearances. Holly was personally inspired to carry out the campaign as her cousin, Loretta Saunders, an Inuit woman from Labrador, went missing and was ultimately found dead on the side of a Canadian highway. After the campaign, the government filed a national DNA missing person's index and introduced 30 safety initiatives to help indigenous women.

#PrayforParis

The epicenter of Paris encountered unexpected terrorist attacks, leading to worldwide efforts to spread awareness about this incident. During this event, terrorists were wearing suicide belts and the subsequent violence was shocking. The terrorists were planning to enter the stadium along with other people. Despite the person being prevented from entering, it demonstrated the severity of how people are risking their own lives, indirectly affecting others. Following the incident, more than 70 million people began to share this news on various social media platforms in order to reach a broader audience. For example, on Facebook, the social media platform enabled users to change their profile picture to a transparent overlay of the French flag. The purpose of changing a user's Facebook profile picture was to indicate support to the victims of this unfortunate event. Twitter was also utilized. However, rather than creating a transparent overlay on a Twitter's user profile, a hashtag was created to emphasize support. This simple hashtag of #PrayforParis allowed users to spread support so that audiences were not only informed about the event, but could also click on a hyperlink to learn more about the cause and other user's perspectives. Although social media platforms were useful in spreading awareness, the effect of younger individuals were just as notable. For example, a young child drew his thoughts on paper, including the message: "Shot after shot, bang after bang, wasting innocent lives!"

#FakeNews

While "fake news" or politically motivated disinformation (PMD) is not a new occurrence, the sentiment and spread of distrust of news coverage has become more notable since the 2016 U.S. elections cycle. The hashtag, #FakeNews, gained major popularity in 2016 when Donald Trump claimed that the negative press coverage he received was due to the spread of false stories. Since the emergence of this hashtag, there has been an increase in policy-related bills and laws regarding the proliferation of inaccurate information globally, which further politicized the issue and raised concerns of impending censorship. The emergence of social media has allowed for "fake news" to spread much quicker than regular news and information, pushing technology companies to take a more active role in detecting and removing "fake news".

"Pope Francis shocks world, endorses Donald Trump for president”

An example of #FakeNews comes from a website named WTOF 5 News. The headline reads: “Pope Francis shocks world, endorses Donald Trump for president” With the help from Facebook, this fake news article received over 960,000 engagements from the popular social media site, making it one of the post popular fake news articles of 2016.

#ProtectOurWinters

Protect Our Winters is a movement and a nonprofit organization started by snowboarder, Jeremy Jones and other winter sport athletes to raise awareness about global warming and climate change. The movement started in 2016 as a response to it being one of the hottest years. The movement demonstrates the effects of global warming with data about the winter sports industry and rise in carbon dioxide percentage. Protect Our Winters or POW calls for people to not only be aware of the effects global warming but to take action by volunteering, voting for legislature or donating to the cause.

#FreeBritney

In April 2019, the Britney Spears fan podcast Britney's Gram uncovered the first alleged abuses within her conservatorship arrangement and created the hashtag #FreeBritney. The term itself had been in use by certain fans since 2008. Alongside advocating for the termination and investigation of Spears's conservatorship, the hashtag and accompanying social movement have been used to raise awareness of guardianship and conservatorship abuse across the United States. The hashtag has led to legislative change in California surrounding legal procedures within conservatorship, and has inspired various bipartisan inquiries of guardianship and conservatorship law in Congress.

#flygskam

Flygskam is a Swedish word that literally translates as “flight shame”. It's the name of an anti-flying movement that originated in Sweden last year, which encourages people to stop taking flights to lower carbon emissions. The idea was originally championed by Olympic athlete Bjorn Ferry and gained momentum after teenage activist Greta Thunberg's mother, the opera singer Malena Ernman, publicly announced she would stop flying, with various Swedish celebrities the following suit. Thunberg herself traveled largely by train during her recent two-week tour of Europe. The activism has seen real results in Sweden as the sales of airline ticket sales declined by 4% in January 2020 due to the increasing public awareness to the carbon footprint resulted by commercial flights.

#CoronaVirus

#Coronavirus, #COVID-19, and #Covid_19 represent a few of the most common hashtags referring to Coronavirus 2019 that started in Wuhan, China. The Hashtag has increased rapidly with the World Health Organization's (WHO) declaration of the virus as pandemic on the 11th of March, 2020. Looking at the trajectory of this Hashtag on Twitter from Symplur, it shows a notable decrease in the number of Hashtags from 50763 on 13 April 2020 to 35795 on 18 April 2020.

#PublishingPaidMe

Created in 2020 by L.L. McKinney, this hashtag was used by authors to discuss the pay differences received by publishers for black and non-black authors.

Political

#ArabSpring

#ArabSpring spread across social media early 2011, spreading awareness of the anti-government protest in the North Africa and the Middle East. The #ArabSpring is Twitter hashtag used in anti-government protests across the Middle East in 2010.

A memorial service held at Harder Stadium after the Isla Vista killings

#NotOneMore

The hashtag #NotOneMore developed shortly after the May 23, 2014, shooting in Isla Vista, Santa Barbara, California. During this incident, six students attending the University of California, Santa Barbara, lost their lives. Richard Martinez, the father of one of the victims, quickly spoke out about gun control, calling for stricter gun control during memorial ceremonies and rallies, chanting "Not One More!" The phrase became a hashtag on social media afterwards. Richard also worked with Everytown's digital team to create a tool to allow participants to send postcards to their senators, congressional representatives, and governor containing the phrase "Not One More."

#NODAPL

#NODAPL, also referred to as the Dakota Access Pipeline protests, is a Twitter hashtag and social media campaign for the struggle against the proposed and partially built Dakota Access Pipeline. The role social media played in this movement is so substantial that the movement itself is now often referred to by its hashtag: #NoDAPL. The hashtag reflected a grassroots campaign that began in early 2016 in reaction to the approved construction of the Dakota Access Pipeline in the northern United States. The Standing Rock Sioux and allied organizations took legal action aimed at stopping construction of the project, while youth from the reservation began a social media campaign which gradually evolved into a larger movement with dozens of associated hashtags. The campaign aimed to raise awareness on the threat of the pipeline on the sacred burial grounds as well as the quality of water in the area. In June 2021, a federal judge struck down the Standing Rock Sioux Tribe's lawsuit, but left the option of reopening the case should any prior orders be violated.
 
The #noDAPL hashtag used in real life, outside social media.

#Oromoprotests

In 2014, IOYA (The International Oromo Youth Association) created the #Oromoprotests hashtag to bring awareness to Oromo student protests against the Ethiopian government's plan to expand Addis Ababa and annex areas occupied by Oromo farmers and residents. The hashtag was utilized again starting in late November/December 2015 to bring attention to renewed Oromo protests and the Ethiopian government's violent crackdown on students, journalists and musicians. While the Oromo held protests before, this was the first time the Oromo could be united across the country by using new social media platforms.

#Sosblakaustralia

In March 2015, an activism campaign took hold in Australia. #Sosblakaustralia was a campaign started in a small aboriginal town in Western Australia. This campaign was to combat an initiative that would close down 150 rural aboriginal communities. Though this movement started in a rural community of 200 #Sosblakaustralia with poor Internet connection, it eventually spread to thousands of followers including Australian celebrities such as Hugh Jackman, this caused the movement to expand as far as London. In 18 days this movement had over 50,000 followers and had reached over 1,000,000 people worldwide.

#IdleNoMore

In the Winter of 2012–2013, in Canada, a campaign was started by Canadian indigenous activists using #IdleNoMore in order to combat future legislation that would threaten indigenous land and water. The movement has continued to grow and unify native communities and the hashtag has made expansion possible. Idle No More started in Canada it has spread to native people around the world including the United States and Australia where indigenous people face similar issues. The use of the hashtag and social media has been instrumental in spreading Idle No More's message to indigenous people around the world giving those who otherwise would be voiceless a means to participate in activism.

#UmbrellaRevolution

A sign of the Umbrella Revolution protest in Hong Kong

The response of the umbrella became a symbol in Admiralty, Mong Kok and Causeway Bay districts, Hong Kong to protest about the free election systems in China. The protestors had been camped on the streets and the public parks. The umbrella was used to protect the protesters in defence of the democratic political process in 2014 when police used tear gas in attempts to get them to leave. "Umbrella Revolution" and "Umbrella Movement" have been used to identify this event through British media outlet BBC. through social network services such as Twitter and Instagram made the events in Hong Kong reach many other people not directly involved with the protest with the use of #UmbrellaRevolution and created a worldwide social awareness to how Hong Kong was responding to support of the democratic process.

#MarchforOurLives

The March for Our Lives protest began after the Marjory Stoneman Douglas High School shooting in Parkland, Florida on February 14, 2018. In response to a surge of gun violence in schools and the 17 dead after the Parkland shooting, people began to rally around the hashtag #neveragain. The hashtag, indicative of the larger movement against gun violence, spread across social networks and went viral in early 2018.

Additionally, the movement organized walkouts in remembrance of the lives lost due to gun violence. In March 2018, hundreds of marches were organized across the country in support of stricter gun laws, many of which were met with resistance from anti-protesters. Since February 2018 there have been 123 laws passed nationwide at the state-level to address concerns of gun control.

On February 17, 2018, a Facebook page was started by students to encourage their participation in the movement; and as of April 2019 the page has been liked by more than 280,000 individuals and has a following of more than 300,000. The Instagram page @marchforourlives is live and as of April 2019 has over 200 posts and just over 360,000 followers.

#PutItToThePeople

The United Kingdom-based People's Vote campaign group was launched in April 2018 and calls for a confirmatory public vote on the final Brexit deal between the United Kingdom and the European Union and uses #PutItToThePeople as its activism hashtag.

#EndFathersDay

In 2014, some editors spoofed being black feminists, spreading the meme, #EndFathersDay. Fox News picked the hoax to denounce. After much research, the fake accounts were outed.

#NoBanNoWall

#NoBanNoWall is a hashtag and social media campaign created in response to Donald Trump's purported "Muslim ban" and 2016 presidential campaign promises to build a physical wall on the US-Mexico border. In 2017, President Donald Trump issued multiple executive orders threatening to break up families and turn away refugees. Saki Barzinji and Imraan Siddiqi started #NoBanNoWall in an effort to rally Muslim, Latino, and other communities to stand up against xenophobic immigration policies. On January 25, 2017, protestors gathered at Washington Square Park and chanted, “No ban; no wall,” which inspired the Twitter hashtag #NoBanNoWall to protest Trump's travel ban. The impact of the movement was seen in airports immediately after the hashtag started trending. A judge in New York accepted a request from the ACLU to provide a warrant blocking deportation in airports. The movement became a platform for people to share stories of them or their families immigrating to the US, and worked to combat the growing public fear of certain foreigners.

#FireDrillFridays

Inspired by Greta Thunberg and started by Greenpeace and Jane Fonda, #FireDrillFridays brings awareness to the climate change crisis. Calling for a Green New Deal in the United States government, the movement organized protests on the Capitol every Friday beginning in October 2019. The campaign also advocates for complete stoppage of new fossil fuel projects and to phase out existing fossil fuel projects. #FireDrillFridays gained popularity with celebrity arrests. Due to the COVID-19 pandemic, Fonda moved #FireDrillFridays online to continue rallying for government action.

#WalkAway

The #WalkAway campaign is a social-media campaign that was launched ahead of the United States 2018 mid-term elections with the stated purpose of encouraging liberals to leave the Democratic Party. The campaign has been organizing events in support of Donald Trump. It was noted and criticized for using astroturfing methods of gathering support, by counterfeiting a popular movement of people who have left the party.

Other examples

In September 2014, The Hokkolorob Movement (Let The Voice Raise Movement) started. It is a series of protests initiated by the students of Jadavpur University in Kolkata, India that began on September 3, 2014. The term "hok kolorob" ("make some noise") was first used as a hashtag on Facebook.

Trends

#icebucketchallenge and #ALS

The #icebucketchallenge is an act where a bucket of ice water is dumped over the head of an individual and documented by videos or pictures, and a "challenge" is issued to another person (or persons) to do the same. The "challenged" individual then either has to respond by dumping ice water on their head, or donate money to a Motor neuron disease or amyotrophic lateral sclerosis (ALS, also referred to as Lou Gehrig's disease) charity. However, doing both is also an option. The encouragement of the challenge is to circulate the video or photo on social media websites and applications with their community, friends, and family to show their support in raising awareness of ALS/MND. The involvement of #icebucketchallenge with the global audience of social media generated so much awareness and support that in early August 2014, the national ALS charity foundation president Barbara Newhouse, directly attributed the movement to a fundraising "surge" of $168,000 that accumulated in just a week. That figure contrasted with the $14,000 raised in the same time the year prior prompted the CEO and her 38 years in the industry to view the difference in support as "crazy." A month after the August 2014 fundraising week the number of videos that were directly associated with the #icebucketchallenge was tallied on the Facebook website from June 1 to September 1 at 17 million, according to the Facebook Newsroom. As the videos continued to climb, so did the challenges. Eventually, public figures such as James Franco, Charlie Rose, and even former president George W. Bush took an activist role in raising money for research and awareness of the ALS disease.

#Hallyu

The Hallyu Wave, which literally translates to “flow of Korea” (or more commonly known as the Korean Wave) represents the social movement in connection to South Korean culture and entertainment. Economically, Hallyu is tremendously profitable, attracting millions of tourists and fans per year and produces many forms of entertainment, such as Korean pop music and television drama series, ultimately generating billions of US dollars in annual revenue which further strengthens its economic prosperity and stability. Furthermore, being a powerful social movement in its own right, Hallyu holds considerable influence in politics as well. The ninth president of South Korea, Roh Moo-hyun, once stated that Hallyu can be used to improve or repair the tense relations between the Koreas. Still, North Korea does not have its own rendition of Hallyu and even rejects it; for example, when Psy's "Gangnam Style" was released in 2012, North Korea viewed the song with contempt because while South Korea was attracting positive attention, it was also undermining the impoverished conditions of North Korea at the same time.

LGBT rights

In 2014, protests of the then-recently enacted anti-gay laws included targeting the corporate sponsors for the 2014 Winter Olympics in Sochi Russia. Among the sponsors was McDonald's, whose marketing included the hashtag #CheersToSochi, which was hijacked by the queer activist group Queer Nation.

In June 2015, The United States Supreme Court ruled in favor of same-sex marriage nationwide. This led to the creation of the hashtag #lovewins. This hashtag earned over 4.5 billion impressions on Twitter. President Barack Obama joined in and tweeted using the hashtag.

#Girlslikeus

Started by Janet Mock in 2012. This hashtag was used to support Jenna Talackova during the Miss Universe pageant.

#DignidadLiteraria

#OwnVoices

This hashtag is used to showcase authors from marginalized or underrepresented groups who write characters from those same groups of people. This hashtag represents stories being told by people who have lived those experiences.

Effectiveness

Hashtag activism has been referred to by critics as a form of slacktivism. Slacktivism is using social media as a vehicle to provide minimal support for a political or social issue. Hashtags, likes, shares, and re-posts are all seen by critics as superficial support that provide minimal change and require little effort. The ease of hashtag activism has led to concerns that it might lead to overuse and public fatigue. Critics worry that hashtag activism allows participants to be satisfied with a public symbol of concern, rather than taking action. The passive nature of the practice can lack the passion once displayed in movements from earlier eras.

Other critiques of hashtag activism stem from the belief that online social movements are often started by privileged individuals, rather than by those who are most affected by the cause itself.

Notable critics of hashtag activism include former Alaska governor Sarah Palin, Canadian journalist Malcolm Gladwell, and Nigerian American writer Teju Cole, who all have argued that hashtag activism encourages lazy, ineffective participation that does not elicit any change.

While critics worry that hashtag activism results in a lack of true action offline, supporters believe it to be an easy and effective way for users to share their opinions, find information, and provide moral support to issues. The hashtag allows users to interact with one another to mobilize efforts without supporters needing to be in the same physical location or the same time of day. As posting a hashtag or reading posts linked to the hashtag requires little effort, more people are able to participate. This can build awareness by connecting it to personal stories, experiences, emotions and thoughts. Identifying shared experiences builds rhetorical connections between people who would never otherwise meet, enabling users of hashtags such as #MeToo and #BlackLivesMatter to support and validate each other and helps to expand and enrich awareness by providing access to multiple narratives.

Supporters such as Bev Goodman, who initiated the #WhyIStayed movement about domestic violence, believe that hashtag activism can begin a chain of events that can lead to sustained engagement and political action. For instance, in 2012 when the Susan G. Komen for the Cure foundation decided to stop funding mammograms through Planned Parenthood, social media users tweeted, #standwithpp, and #singon; later that same week, Komen reversed its decision. Social media fosters a fast-paced environment that allows organizations to quickly see how individuals react to policies and decisions, which in turn creates the opportunity for those responses to be taken into account if the organization is open to changing the policy or decision.

Monday, September 26, 2022

Biodiversity action plan

From Wikipedia, the free encyclopedia

A biodiversity action plan (BAP) is an internationally recognized program addressing threatened species and habitats and is designed to protect and restore biological systems. The original impetus for these plans derives from the 1992 Convention on Biological Diversity (CBD). As of 2009, 191 countries have ratified the CBD, but only a fraction of these have developed substantive BAP documents.

The principal elements of a BAP typically include: (a) preparing inventories of biological information for selected species or habitats; (b) assessing the conservation status of species within specified ecosystems; (c) creation of targets for conservation and restoration; and (d) establishing budgets, timelines and institutional partnerships for implementing the BAP.

Species plans

Snow leopard, Pakistan, an endangered species

A fundamental method of engagement to a BAP is thorough documentation regarding individual species, with emphasis upon the population distribution and conservation status. This task, while fundamental, is highly daunting, since only an estimated ten percent of the world’s species are believed to have been characterized as of 2006, most of these unknowns being fungi, invertebrate animals, micro-organisms and plants. For many bird, mammal and reptile species, information is often available in published literature; however, for fungi, invertebrate animals, micro-organisms and many plants, such information may require considerable local data collection. It is also useful to compile time trends of population estimates in order to understand the dynamics of population variability and vulnerability. In some parts of the world complete species inventories are not realistic; for example, in the Madagascar dry deciduous forests, many species are completely undocumented and much of the region has never even been systematically explored by scientists.

A species plan component of a country’s BAP should ideally entail a thorough description of the range, habitat, behaviour, breeding and interaction with other species. Once a determination has been made of conservation status (e.g. rare, endangered, threatened, vulnerable), a plan can then be created to conserve and restore the species population to target levels. Examples of programmatic protection elements are: habitat restoration; protection of habitat from urban development; establishment of property ownership; limitations on grazing or other agricultural encroachment into habitat; reduction of slash-and-burn agricultural practises; outlawing killing or collecting the species; restrictions on pesticide use; and control of other environmental pollution. The plan should also articulate which public and private agencies should implement the protection strategy and indicate budgets available to execute this strategy.

Agricultural Plans

Agricultural practices can reduce the biodiversity of a region significantly. Biodiversity Action Plans for agricultural production are necessary to ensure a biodiversity friendly production. It has not been common for companies to integrate biodiversity aspects into their value chain, but some companies and organizations have shown overall efforts for implementing better practices.

An existing example for guidelines on biodiversity practices in agriculture is the Biodiversity Action Plan for spice production in India. By planning and implementing biodiversity friendly measures, farmers can mitigate negative impacts and support positive influences.

Habitat plans

Where a number of threatened species depend upon a specific habitat, it may be appropriate to prepare a habitat protection element of the Biodiversity Action Plan. Examples of such special habitats are: raised acidic bogs of Scotland; Waterberg Biosphere bushveld in South Africa; California’s coastal wetlands; and Sweden’s Stora Alvaret on the island of Öland. In this case also, careful inventories of species and also the geographic extent and quality of the habitat must be documented. Then, as with species plans, a program can be created to protect, enhance and/or restore habitat using similar strategies as discussed above under the species plans.

Specific countries

Some examples of individual countries which have produced substantive Biodiversity Action Plans follow. In every example the plans concentrate on plants and vertebrate animals, with very little attention to neglected groups such as fungi, invertebrate animals and micro-organisms, even though these are also part of biodiversity. Preparation of a country BAP may cost up to 100 million pounds sterling, with annual maintenance costs roughly ten percent of the initial cost. If plans took into account neglected groups, the cost would be higher. Obviously costs for countries with small geographical area or simplified ecosystems have a much lesser cost. For example, the St. Lucia BAP has been costed in the area of several million pounds sterling.

Australia

Australia has developed a detailed and rigorous Biodiversity Action Plan. This document estimates that the total number of indigenous species may be 560,000, many of which are endemic. A key element of the BAP is protection of the Great Barrier Reef, which is actually in a much higher state of health than most of the world’s reefs, Australia having one of the highest percentages of treated wastewater. There are however serious ongoing concerns, particularly in regards to the ongoing negative impact on water quality from land use practices. Also, climate change impact is feared to be significant.

Considerable analysis has been conducted on the sustainable yield of firewood production, a major threat to deforestation in most tropical countries. Biological inventory work; assessment of harvesting practices; and computer modeling of the dynamics of treefall, rot and harvest; have been carried out to adduce data on safe harvesting rates. Extensive research has also been conducted on the relation of brush clearance to biodiversity decline and impact on water tables; for example, these effects have been analyzed in the Toolibin Lake wetlands region.

New Zealand

New Zealand has ratified the Convention on Biological Diversity and as part of The New Zealand Biodiversity Strategy and Biodiversity Action Plans are implemented on ten separate themes.

Local government and some companies also have their own Biodiversity Action Plan.

St. Lucia

The St. Lucia BAP recognizes impacts of large numbers of tourists to the marine and coastal diversity of the Soufrière area of the country. The BAP specifically acknowledges that the carrying capacity for human use and water pollution discharge of sensitive reef areas was exceeded by the year 1990. The plan also addresses conservation of the historic island fishing industry. In 1992, several institutions in conjunction with native fishermen to produce a sustainable management plan for fishery resources, embodied in the Soufrière Marine Management Area.

The St. Lucia BAP features significant involvement from the University of the West Indies. Specific detailed attention is given to three species of threatened marine turtles, to a variety of vulnerable birds and a number of pelagic fishes and cetaceans. In terms of habitat conservation the plan focusses attention on the biologically productive mangrove swamps and notes that virtually all mangrove areas had already come under national protection by 1984.

Tanzania

The Tanzania national BAP addresses issues related to sustainable use of Lake Manyara, an extensive freshwater lake, whose usage by humans accelerated in the period 1950 to 1990. The designation of the Lake Manyara Biosphere Reserve under UNESCO's Man and the Biosphere Programme in 1981 combines conservation of the lake and surrounding high value forests with sustainable use of the wetlands area and simple agriculture. This BAP has united principal lake users in establishing management targets. The biosphere reserve has induced sustainable management of the wetlands, including monitoring groundwater and the chemistry of the escarpment water source.

United Kingdom

Fowlsheugh cliffs, Scotland, a protected seabird breeding habitat

The United Kingdom Biodiversity Action Plan covers not only terrestrial species associated with lands within the UK, but also marine species and migratory birds, which spend a limited time in the UK or its offshore waters. The UK plan encompasses "391 Species Action Plans, 45 Habitat Action Plans and 162 Local Biodiversity Action Plans with targeted actions". This plan is noteworthy because of its extensive detail, clarity of endangerment mechanisms, specificity of actions, follow up monitoring program and its inclusion of migrating cetaceans and pelagic birds.

On August 28, 2007, the new Biodiversity Action Plan (BAP) [launched in 1997] identified 1,149 species and 65 habitats in the UK that needed conservation and greater protection. The updated list included the hedgehog, house sparrow, grass snake and the garden tiger moth, while otters, bottlenose dolphins and red squirrels remained in need of habitat protection.

In May 2011, the European Commission adopted a new strategy to halt the loss of biodiversity and ecosystem services in the EU by 2020, in line with the commitments made at the 10th meeting of the Convention on Biological Diversity (CBD) held in Nagoya, Japan in 2010. In 2012 the UK BAP was succeeded by the 'UK Post-2010 Biodiversity Framework'.

UK BAP website

To support the work of the UK BAP, the UK BAP website was created by JNCC in 2001. The website contained information on the BAP process, hosted all relevant documents, and provided news and relevant updates. In March 2011, as part of the UK government’s review of websites, the UK BAP site was ‘closed’, and the core content was migrated into the JNCC website. Content from the original UK BAP website has been archived by the National Archives as snapshots from various dates (for example, UK BAP: copy March 2011; copy 2012).

United States

Twenty-six years prior to the international biodiversity convention, the United States had launched a national program to protect threatened species in the form of the 1966 Endangered Species Act. The legislation created broad authority for analyzing and listing species of concern, and mandated that Species Recovery Plans be created. Thus, while the USA is an unratified signer of the accord, arguably it has the longest track record and most comprehensive program of species protection of any country. There are about 7000 listed species (e.g. endangered or threatened), of which about half have approved Recovery Plans. While this number of species seems high compared to other countries, the value is rather indicative of the total number of species characterized, which is extremely large.

Uzbekistan

Five major divisions of habitat have been identified in Uzbekistan’s BAP: Wetlands (including reed habitat and man-made marsh); desert ecosystems (including sandy, stony and clay); steppes; riparian ecosystems; and mountain ecosystems. Over 27,000 species have been inventoried in the country, with a high rate of endemism for fishes and reptiles. Principal threats to biodiversity are related to human activities associated with overpopulation and generally related to agricultural intensification. Major geographic regions encompassed by the BAP include the Aral Sea Programme (threatened by long-term drainage and salination, largely for cotton production), the Nuratau Biosphere Reserve, and the Western Tien Shan Mountains Programme (in conjunction with Kazakhstan and Kyrgyzstan).

Criticism

Some developing countries criticize the emphasis of BAPs, because these plans inherently favour consideration of wildlife protection above food and industrial production, and in some cases may represent an obstacle to population growth. The plans are costly to produce, a fact which makes it difficult for many smaller countries and poorer countries to comply. In terms of the plans themselves, many countries have adopted pro-forma plans including little research and even less in the way of natural resource management. Almost universally, this has resulted in plans which emphasize plants and vertebrate animals, and which overlook fungi, invertebrate animals and micro-organisms. With regard to specific world regions, there is a notable lack of substantive participation by most of the Middle Eastern countries and much of Africa, the latter of which may be impeded by economic considerations of plan preparation. Some governments such as the European Union have diverted the purpose of a biodiversity action plan, and implemented the convention accord by a set of economic development policies with referencing certain ecosystems' protection.

Biodiversity planning: a new way of thinking

The definition of biodiversity under the Convention on Biological Diversity now recognises that biodiversity is a combination of ecosystem structure and function, as much as its components e.g. species, habitats and genetic resources. Article 2 states:

in addressing the boundless complexity of biological diversity, it has become conventional to think in hierarchical terms, from the genetic material within individual cells, building up through individual organisms, populations, species and communities of species, to the biosphere overall...At the same time, in seeking to make management intervention as efficient as possible, it is essential to take an holistic view of biodiversity and address the interactions that species have with each other and their non-living environment, i.e. to work from an ecological perspective.

The World Summit on Sustainable Development endorsed the objectives of the Convention on Biological Diversity to “achieve by 2010 a significant reduction of the current rate of biodiversity loss at the global, regional and national level as a contribution to poverty alleviation and to the benefit of life on Earth”. To achieve this outcome, biodiversity management will depend on maintaining structure and function.

Biodiversity is not singularly definable but may be understood via a series of management principles under BAPs, such as:

1. that biodiversity is conserved across all levels and scales – structure, function and composition are conserved at site, regional, state and national scales. 2. that examples of all ecological communities are adequately managed for conservation. 3. ecological communities are managed to support and enhance viable populations of animals, fungi, micro-organisms and plants and ecological functions.

Biodiversity and wildlife are not the same thing. The traditional focus on threatened species in BAPs is at odds with the principles of biodiversity management because, by the time species become threatened, the processes that maintain biodiversity are already compromised. Individual species are also regarded as generally poor indicators of biodiversity when it comes to actual planning. A species approach to BAPs only serves to identify and at best, apply a patch to existing problems. Increasingly, biodiversity planners are looking through the lens of ecosystem services. Critics of biodiversity are often confusing the need to protect species (their intrinsic value) with the need to maintain ecosystem processes, which ultimately maintain human society and do not compromise economic development. Hence, a core principle of biodiversity management, that traditional BAPs overlook, is the need to incorporate cultural, social and economic values in the process.

Modern day BAPs use an analysis of ecosystem services, key ecological process drivers, and use species as one of many indicators of change. They would seek to maintain structure and function by addressing habitat connectivity and resilience and may look at communities of species (threatened or otherwise) as one method of monitoring outcomes. Ultimately, species are the litmus test for biodiversity – viable populations of species can only be expected to exist in relatively intact habitats. However, the rationale behind BAPs is to "conserve and restore" biodiversity. One of the fastest developing areas of management is biodiversity offsets. The principles are in keeping with ecological impact assessment, which in turn depends on good quality BAPs for evaluation. Contemporary principles of biodiversity management, such as those produced by the Business Biodiversity Offsets Program are now integral to any plans to manage biodiversity, including the development of BAPs.

Bird flight

From Wikipedia, the free encyclopedia
 
A flock of domestic pigeons each in a different phase of its flap.

Bird flight is the primary mode of locomotion used by most bird species in which birds take off and fly. Flight assists birds with feeding, breeding, avoiding predators, and migrating.

Bird flight is one of the most complex forms of locomotion in the animal kingdom. Each facet of this type of motion, including hovering, taking off, and landing, involves many complex movements. As different bird species adapted over millions of years through evolution for specific environments, prey, predators, and other needs, they developed specializations in their wings, and acquired different forms of flight.

Various theories exist about how bird flight evolved, including flight from falling or gliding (the trees down hypothesis), from running or leaping (the ground up hypothesis), from wing-assisted incline running or from proavis (pouncing) behavior.

Basic mechanics of bird flight

Lift, Drag and Thrust

The fundamentals of bird flight are similar to those of aircraft, in which the aerodynamic forces sustaining flight are lift, drag, and thrust. Lift force is produced by the action of air flow on the wing, which is an airfoil. The airfoil is shaped such that the air provides a net upward force on the wing, while the movement of air is directed downward. Additional net lift may come from airflow around the bird's body in some species, especially during intermittent flight while the wings are folded or semi-folded (cf. lifting body).

Aerodynamic drag is the force opposite to the direction of motion, and hence the source of energy loss in flight. The drag force can be separated into two portions, lift-induced drag, which is the inherent cost of the wing producing lift (this energy ends up primarily in the wingtip vortices), and parasitic drag, including skin friction drag from the friction of air and body surfaces and form drag from the bird's frontal area. The streamlining of bird's body and wings reduces these forces. Unlike aircraft, which have engines to produce thrust, birds flap their wings with a given flapping amplitude and frequency to generate thrust.

Flight

Birds use mainly three types of flight, distinguished by wing motion.

Gliding flight

Lesser flamingos flying in formation.

When in gliding flight, the upward aerodynamic force is equal to the weight. In gliding flight, no propulsion is used; the energy to counteract the energy loss due to aerodynamic drag is either taken from the potential energy of the bird, resulting in a descending flight, or is replaced by rising air currents ("thermals"), referred to as soaring flight. For specialist soaring birds (obligate soarers), the decision to engage in flight are strongly related to atmospheric conditions that allow individuals to maximise flight-efficiency and minimise energetic costs.

Flapping flight

When a bird flaps, as opposed to gliding, its wings continue to develop lift as before, but the lift is rotated forward to provide thrust, which counteracts drag and increases its speed, which has the effect of also increasing lift to counteract its weight, allowing it to maintain height or to climb. Flapping involves two stages: the down-stroke, which provides the majority of the thrust, and the up-stroke, which can also (depending on the bird's wings) provide some thrust. At each up-stroke the wing is slightly folded inwards to reduce the energetic cost of flapping-wing flight. Birds change the angle of attack continuously within a flap, as well as with speed.

Bounding flight

Small birds often fly long distances using a technique in which short bursts of flapping are alternated with intervals in which the wings are folded against the body. This is a flight pattern known as "bounding" or "flap-bounding" flight. When the bird's wings are folded, its trajectory is primarily ballistic, with a small amount of body lift. The flight pattern is believed to decrease the energy required by reducing the aerodynamic drag during the ballistic part of the trajectory, and to increase the efficiency of muscle use.

Hovering

The ruby-throated hummingbird can beat its wings 52 times a second.
 
Several bird species use hovering, with one family specialized for hovering – the hummingbirds. True hovering occurs by generating lift through flapping alone, rather than by passage through the air, requiring considerable energy expenditure. This usually confines the ability to smaller birds, but some larger birds, such as a kite or osprey can hover for a short period of time. Although not a true hover, some birds remain in a fixed position relative to the ground or water by flying into a headwind. Hummingbirds, kestrels, terns and hawks use this wind hovering.

Most birds that hover have high aspect ratio wings that are suited to low speed flying. Hummingbirds are a unique exception – the most accomplished hoverers of all birds. Hummingbird flight is different from other bird flight in that the wing is extended throughout the whole stroke, which is a symmetrical figure of eight, with the wing producing lift on both the up- and down-stroke. Hummingbirds beat their wings at some 43 times per second, while others may be as high as 80 times per second.

Take-off and landing

A male bufflehead runs atop the water while taking off.
 
A magpie-goose taking off.
 

Take-off is one of the most energetically demanding aspects of flight, as the bird must generate enough airflow across the wing to create lift. Small birds do this with a simple upward jump. However, this technique does not work for larger birds, such as albatrosses and swans, which instead must take a running start to generate sufficient airflow. Large birds take off by facing into the wind, or, if they can, by perching on a branch or cliff so they can just drop off into the air.

Landing is also a problem for large birds with high wing loads. This problem is dealt with in some species by aiming for a point below the intended landing area (such as a nest on a cliff) then pulling up beforehand. If timed correctly, the airspeed once the target is reached is virtually nil. Landing on water is simpler, and the larger waterfowl species prefer to do so whenever possible, landing into wind and using their feet as skids. To lose height rapidly prior to landing, some large birds such as geese indulge in a rapid alternating series of sideslips or even briefly turning upside down in a maneuver termed whiffling.

Wings

A kea in flight.

The bird's forelimbs (the wings) are the key to flight. Each wing has a central vane to hit the wind, composed of three limb bones, the humerus, ulna and radius. The hand, or manus, which ancestrally was composed of five digits, is reduced to three digits (digit II, III and IV or I, II, III depending on the scheme followed), which serves as an anchor for the primaries, one of two groups of flight feathers responsible for the wing's airfoil shape. The other set of flight feathers, behind the carpal joint on the ulna, are called the secondaries. The remaining feathers on the wing are known as coverts, of which there are three sets. The wing sometimes has vestigial claws. In most species, these are lost by the time the bird is adult (such as the highly visible ones used for active climbing by hoatzin chicks), but claws are retained into adulthood by the secretarybird, screamers, finfoots, ostriches, several swifts and numerous others, as a local trait, in a few specimens.

Albatrosses have locking mechanisms in the wing joints that reduce the strain on the muscles during soaring flight.

Even within a species wing morphology may differ. For example, adult European Turtle Doves have been found to have longer but more rounded wings than juveniles – suggesting that juvenile wing morphology facilitates their first migrations, while selection for flight maneuverability is more important after the juveniles' first molt.

Female birds exposed to predators during ovulation produce chicks that grow their wings faster than chicks produced by predator-free females. Their wings are also longer. Both adaptations may make them better at avoiding avian predators.

Wing shape

Wing shapes

The shape of the wing is important in determining the flight capabilities of a bird. Different shapes correspond to different trade-offs between advantages such as speed, low energy use, and maneuverability. Two important parameters are the aspect ratio and wing loading. Aspect ratio is the ratio of wingspan to the mean of its chord (or the square of the wingspan divided by wing area). A high aspect ratio results in long narrow wings that are useful for endurance flight because they generate more lift. Wing loading is the ratio of weight to wing area.

Most kinds of bird wing can be grouped into four types, with some falling between two of these types. These types of wings are elliptical wings, high speed wings, high aspect ratio wings and slotted high-lift wings.

The budgerigar's wings, as seen on this pet female, allow it excellent manoeuvrability.

Elliptical wings

Technically, elliptical wings are those having elliptical (that is quarter ellipses) meeting conformally at the tips. The early model Supermarine Spitfire is an example. Some birds have vaguely elliptical wings, including the albatross wing of high aspect ratio. Although the term is convenient, it might be more precise to refer to curving taper with fairly small radius at the tips. Many small birds have a low aspect ratio with elliptical character (when spread), allowing for tight maneuvering in confined spaces such as might be found in dense vegetation. As such they are common in forest raptors (such as Accipiter hawks), and many passerines, particularly non-migratory ones (migratory species have longer wings). They are also common in species that use a rapid take off to evade predators, such as pheasants and partridges.

High speed wings

High speed wings are short, pointed wings that when combined with a heavy wing loading and rapid wingbeats provide an energetically expensive high speed. This type of flight is used by the bird with the fastest wing speed, the peregrine falcon, as well as by most of the ducks. Birds that make long migrations typically have this type of wing. The same wing shape is used by the auks for a different purpose; auks use their wings to "fly" underwater.

The peregrine falcon has the highest recorded dive speed of 242 miles per hour (389 km/h). The fastest straight, powered flight is the spine-tailed swift at 105 mph (169 km/h).

A roseate tern uses its low wing loading and high aspect ratio to achieve low speed flight.

High aspect ratio wings

High aspect ratio wings, which usually have low wing loading and are far longer than they are wide, are used for slower flight. This may take the form of almost hovering (as used by kestrels, terns and nightjars) or in soaring and gliding flight, particularly the dynamic soaring used by seabirds, which takes advantage of wind speed variation at different altitudes (wind shear) above ocean waves to provide lift. Low speed flight is also important for birds that plunge-dive for fish.

Soaring wings with deep slots

These wings are favored by larger species of inland birds, such as eagles, vultures, pelicans, and storks. The slots at the end of the wings, between the primaries, reduce the induced drag and wingtip vortices by "capturing" the energy in air flowing from the lower to upper wing surface at the tips, whilst the shorter size of the wings aids in takeoff (high aspect ratio wings require a long taxi to get airborne).

Coordinated formation flight

A wide variety of birds fly together in a symmetric V-shaped or a J-shaped coordinated formation, also referred to as an "echelon", especially during long-distance flight or migration. It is often assumed that birds resort to this pattern of formation flying in order to save energy and improve the aerodynamic efficiency. The birds flying at the tips and at the front would interchange positions in a timely cyclical fashion to spread flight fatigue equally among the flock members.

The wingtips of the leading bird in an echelon create a pair of opposite rotating line vortices. The vortices trailing a bird have an underwash part behind the bird, and at the same time they have an upwash on the outside, that hypothetically could aid the flight of a trailing bird. In a 1970 study the authors claimed that each bird in a V formation of 25 members can achieve a reduction of induced drag and as a result increase their range by 71%. It has also been suggested that birds' wings produce induced thrust at their tips, allowing for proverse yaw and net upwash at the last quarter of the wing. This would allow birds to overlap their wings and gain Newtonian lift from the bird in front.

Studies of waldrapp ibis show that birds spatially coordinate the phase of wing flapping and show wingtip path coherence when flying in V positions, thus enabling them to maximally utilise the available energy of upwash over the entire flap cycle. In contrast, birds flying in a stream immediately behind another do not have wingtip coherence in their flight pattern and their flapping is out of phase, as compared to birds flying in V patterns, so as to avoid the detrimental effects of the downwash due to the leading bird's flight.

Adaptations for flight

Diagram of the wing of a chicken, top view

The most obvious adaptation to flight is the wing, but because flight is so energetically demanding birds have evolved several other adaptations to improve efficiency when flying. Birds' bodies are streamlined to help overcome air-resistance. Also, the bird skeleton is hollow to reduce weight, and many unnecessary bones have been lost (such as the bony tail of the early bird Archaeopteryx), along with the toothed jaw of early birds, which has been replaced with a lightweight beak. The skeleton's breastbone has also adapted into a large keel, suitable for the attachment of large, powerful flight muscles. The vanes of each feather have hooklets called barbules that zip the vanes of individual feathers together, giving the feathers the strength needed to hold the airfoil (these are often lost in flightless birds). The barbules maintain the shape and function of the feather. Each feather has a major (greater) side and a minor (lesser) side, meaning that the shaft or rachis does not run down the center of the feather. Rather it runs longitudinally off the center with the lesser or minor side to the front and the greater or major side to the rear of the feather. This feather anatomy, during flight and flapping of the wings, causes a rotation of the feather in its follicle. The rotation occurs in the up motion of the wing. The greater side points down, letting air slip through the wing. This essentially breaks the integrity of the wing, allowing for a much easier movement in the up direction. The integrity of the wing is reestablished in the down movement, which allows for part of the lift inherent in bird wings. This function is most important in taking off or achieving lift at very low or slow speeds where the bird is reaching up and grabbing air and pulling itself up. At high speeds the air foil function of the wing provides most of the lift needed to stay in flight.

The large amounts of energy required for flight have led to the evolution of a unidirectional pulmonary system to provide the large quantities of oxygen required for their high respiratory rates. This high metabolic rate produces large quantities of radicals in the cells that can damage DNA and lead to tumours. Birds, however, do not suffer from an otherwise expected shortened lifespan as their cells have evolved a more efficient antioxidant system than those found in other animals.

Evolution of bird flight

Most paleontologists agree that birds evolved from small theropod dinosaurs, but the origin of bird flight is one of the oldest and most hotly contested debates in paleontology. The four main hypotheses are:

  • From the trees down, that birds' ancestors first glided down from trees and then acquired other modifications that enabled true powered flight.
  • From the ground up, that birds' ancestors were small, fast predatory dinosaurs in which feathers developed for other reasons and then evolved further to provide first lift and then true powered flight.
  • Wing-assisted incline running (WAIR), a version of "from the ground up" in which birds' wings originated from forelimb modifications that provided downforce, enabling the proto-birds to run up extremely steep slopes such as the trunks of trees.
  • Pouncing proavis, which posits that flight evolved by modification from arboreal ambush tactics.

There has also been debate about whether the earliest known bird, Archaeopteryx, could fly. It appears that Archaeopteryx had the avian brain structures and inner-ear balance sensors that birds use to control their flight. Archaeopteryx also had a wing feather arrangement like that of modern birds and similarly asymmetrical flight feathers on its wings and tail. But Archaeopteryx lacked the shoulder mechanism by which modern birds' wings produce swift, powerful upstrokes; this may mean that it and other early birds were incapable of flapping flight and could only glide. The presence of most fossils in marine sediments in habitats devoid of vegetation has led to the hypothesis that they may have used their wings as aids to run across the water surface in the manner of the basilisk lizards.

In March 2018, scientists reported that Archaeopteryx was likely capable of flight, but in a manner substantially different from that of modern birds.

From the trees down

It is unknown how well Archaeopteryx could fly, or if it could even fly at all.

This was the earliest hypothesis, encouraged by the examples of gliding vertebrates such as flying squirrels. It suggests that proto-birds like Archaeopteryx used their claws to clamber up trees and glided off from the tops.

Some recent research undermines the "trees down" hypothesis by suggesting that the earliest birds and their immediate ancestors did not climb trees. Modern birds that forage in trees have much more curved toe-claws than those that forage on the ground. The toe-claws of Mesozoic birds and of closely related non-avian theropod dinosaurs are like those of modern ground-foraging birds.

From the ground up

Feathers have been discovered in a variety of coelurosaurian dinosaurs (including the early tyrannosauroid Dilong). Modern birds are classified as coelurosaurs by nearly all palaeontologists. The original functions of feathers may have included thermal insulation and competitive displays. The most common version of the "from the ground up" hypothesis argues that bird's ancestors were small ground-running predators (rather like roadrunners) that used their forelimbs for balance while pursuing prey and that the forelimbs and feathers later evolved in ways that provided gliding and then powered flight. Another "ground upwards" theory argues the evolution of flight was initially driven by competitive displays and fighting: displays required longer feathers and longer, stronger forelimbs; many modern birds use their wings as weapons, and downward blows have a similar action to that of flapping flight. Many of the Archaeopteryx fossils come from marine sediments and it has been suggested that wings may have helped the birds run over water in the manner of the common basilisk.

Most recent attacks on the "from the ground up" hypothesis attempt to refute its assumption that birds are modified coelurosaurian dinosaurs. The strongest attacks are based on embryological analyses, which conclude that birds' wings are formed from digits 2, 3 and 4 (corresponding to the index, middle and ring fingers in humans; the first of a bird's 3 digits forms the alula, which they use to avoid stalling on low-speed flight, for example when landing); but the hands of coelurosaurs are formed by digits 1, 2 and 3 (thumb and first 2 fingers in humans). However these embryological analyses were immediately challenged on the embryological grounds that the "hand" often develops differently in clades that have lost some digits in the course of their evolution, and therefore bird's hands do develop from digits 1, 2 and 3.

Wing-assisted incline running

The wing-assisted incline running (WAIR) hypothesis was prompted by observation of young chukar chicks, and proposes that wings developed their aerodynamic functions as a result of the need to run quickly up very steep slopes such as tree trunks, for example to escape from predators. Note that in this scenario birds need downforce to give their feet increased grip. But early birds, including Archaeopteryx, lacked the shoulder mechanism that modern birds' wings use to produce swift, powerful upstrokes. Since the downforce that WAIR requires is generated by upstrokes, it seems that early birds were incapable of WAIR.

Pouncing proavis model

The proavis theory was first proposed by Garner, Taylor, and Thomas in 1999:

We propose that birds evolved from predators that specialized in ambush from elevated sites, using their raptorial hindlimbs in a leaping attack. Drag–based, and later lift-based, mechanisms evolved under selection for improved control of body position and locomotion during the aerial part of the attack. Selection for enhanced lift-based control led to improved lift coefficients, incidentally turning a pounce into a swoop as lift production increased. Selection for greater swooping range would finally lead to the origin of true flight.

The authors believed that this theory had four main virtues:

  • It predicts the observed sequence of character acquisition in avian evolution.
  • It predicts an Archaeopteryx-like animal, with a skeleton more or less identical to terrestrial theropods, with few adaptations to flapping, but very advanced aerodynamic asymmetrical feathers.
  • It explains that primitive pouncers (perhaps like Microraptor) could coexist with more advanced fliers (like Confuciusornis or Sapeornis) since they did not compete for flying niches.
  • It explains that the evolution of elongated rachis-bearing feathers began with simple forms that produced a benefit by increasing drag. Later, more refined feather shapes could begin to also provide lift.

Uses and loss of flight in modern birds

Birds use flight to obtain prey on the wing, for foraging, to commute to feeding grounds, and to migrate between the seasons. It is also used by some species to display during the breeding season and to reach safe isolated places for nesting.

Flight is more energetically expensive in larger birds, and many of the largest species fly by soaring and gliding (without flapping their wings) as much as possible. Many physiological adaptations have evolved that make flight more efficient.

Birds that settle on isolated oceanic islands that lack ground-based predators may over the course of evolution lose the ability to fly. One such example is the flightless cormorant, native to the Galápagos Islands. This illustrates both flight's importance in avoiding predators and its extreme demand for energy.

Lie point symmetry

From Wikipedia, the free encyclopedia https://en.wikipedia.org/wiki/Lie_point_symmetry     ...