Friday, June 19, 2020

Trump rally in Tulsa, a day after Juneteenth, awakens memories of 1921 racist massacre

*The Greenwood section of Tulsa, Okla., is seen in flames during in 1921 during one of the worst acts of anti-Black racism in American history. (Creative Commons), CC BY-SA*

Russell Cobb, University of Alberta

For only the second time in a century, the world’s attention is focused on Tulsa, Okla. You would be forgiven for thinking Tulsa is a sleepy town “where the wind comes sweepin’ down the plain,” in the words of the musical Oklahoma!.

But Tulsa was the site of one of the worst episodes of racial violence in American history, and a long, arduous process of reconciliation over the Tulsa Race Massacre of 1921 was jarred by President Donald Trump’s decision to hold his first campaign rally there since the COVID-19 pandemic began.

The city is on edge. Emotions are raw. There’s anxiety about a spike in coronavirus cases, but lurking even deeper in the collective psyche is a fear that history could repeat itself. Tens of thousands of Trump supporters will gather close to a neighbourhood still reckoning with a white invasion that claimed hundreds of Black lives.

In this June 15, 2020, photo, people walk past a Black Wall Street mural in the Greenwood district in Tulsa, Okla. Dozens of blocks of Black-owned businesses were destroyed by a white mob in deadly race riots nearly a century ago. (AP Photo/Sue Ogrocki)

A Trump rally near a site of a race massacre during a global pandemic already sounded like a recipe for a dangerous social experiment. But then there was the matter of timing. The rally was to be held on Juneteenth (June 19), a holiday commemorating the day slaves in the western portion of the Confederacy finally gained their freedom.
Normally, Juneteenth in Tulsa is one big party, the rare event that brings white and Black Oklahomans together. But fears about spreading COVID-19 led organizers to cancel the event. Then came the protests over the murder of George Floyd. During those demonstrations in Tulsa, a truck ran through a blockade of traffic, causing one demonstrator to fall from a bridge. He is paralyzed from the waist down.

COVID-19 cases surging

To make a bad situation even worse, the city is witnessing a surge in coronavirus cases. Local health officials have acknowledged that the increase in new cases, mixed with close to 20,000 people packed into an arena, is “a perfect storm” that could fuel a super-spreader event.

Tulsa Mayor G.T. Bynum speaks during a news conference at police headquarters. (Matt Barnard/Tulsa World via AP)

Some of Mayor G.T. Bynum’s biggest supporters began pleading with him to cancel the event. Bynum is of that rarest of species, a Republican who has staked part of his political legacy on combating racism. It was Bynum who shocked the white establishment by ordering an investigation into potential mass grave sites from the 1921 massacre, even as many Republicans accused him of opening old wounds.
Faced with the prospect of provoking a fight with Trump, however, Bynum equivocated.

Bynum found himself under attack from former friends and allies who urged him to do something. Then, on June 13, the Trump campaign announced that it would change the date of the rally to June 20 “out of respect” for Juneteenth. It was a small victory for protesters, but some were further enraged by Bynum’s moral equivalence between the protests over Floyd’s murder and a Trump campaign rally.

Reminiscent of another mayor

The mayor’s impotence has also brought back memories of 1921. The mayor then, T.D. Evans, found himself unable — or unwilling — to stand between an angry white mob ginned up over fears of a “Black uprising” and a Black community demanding racial equality.
Evans saw the rising influence of the Ku Klux Klan in Oklahoma politics and quietly voiced his displeasure. As the Tulsa Tribune cultivated white paranoia about a Black invasion of white Tulsa, Evans, and many like him, did little. “Despite warnings from Blacks and whites that trouble was brewing,” Tulsa Word reporter Randy Krehbiel wrote in a book about the massacre, “(Evans) remained mostly silent.”

In this 1921 file image provided by the Greenwood Cultural Center, Mt. Zion Baptist Church burns after being torched by white mobs during the 1921 Tulsa massacre. (Greenwood Cultural Center via Tulsa World via AP)

One historical parallel with 1921 stands out above the rest: the power and influence of “fake news” to mobilize alienated voters.
While much has been made of a revolution of social media and YouTube to undercut the gatekeepers of traditional media, a false news article was the most proximate cause of the Tulsa Race Massacre of 1921.
The Tulsa Tribune published an article on May 30, 1921, with an unproven allegation that a Black man, Dick Rowland, had tried to rape a white woman in a downtown elevator. The dog-whistle came through loud and clear. No evidence was presented and charges were later dropped. But the news was enough to set off calls for a lynching of Rowland.

Hundreds killed

A mob formed around the Tulsa courthouse. The Tribune had been stoking fears of a “Black uprising” for months, running stories of race mixing, jazz and interracial dancing at Black road houses.
A few Blacks armed themselves and tried to stop the lynching. The sight of armed Blacks made the white mob direct its fury at a bigger target — the Black section of town, Greenwood.
By the dawn of June 1, 1921, Greenwood lay in ruins, with hundreds dead and thousands interned in camps. The devastation did not come as a surprise to those who had watched the rise of xenophobia during the First World War and the second coming of the KKK, an organization that received a boost after the screening of the racist film The Birth of a Nation in 1915 at the White House.

Trump reaches into his suit jacket to read remarks following the events in Charlottesville, Va. He defended white supremacists following a Unite the Right rally that turned violent. (AP Photo/Pablo Martinez Monsivais)

Tulsa, and the nation, had been primed for racial violence by a white supremacist media and presidential administration. Many well-intentioned people stood idly by, hoping the trouble would soon blow over. It did not.
Karl Marx wrote that history repeats itself, the first time as tragedy, the second as farce. During the spring of 1921, Tulsa got the tragedy. With Trump rallying tens of thousands of his supporters near Greenwood amid a deadly pandemic, the best we can hope for this time around is farce.
Russell Cobb, Associate Professor of Latin American Studies, University of Alberta
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Fighting fire with fire: Botswana adopts Indigenous Australians' ancient burning tradition

Sam Johnston, University of Melbourne
Interest in Aboriginal fire knowledge has been high since last summer’s terrible bushfires. One initiative shows the huge potential benefits of this ancient practice – not just in Australia, but globally.
The International Savanna Fire Management Initiative (ISFMI) is taking the fire management techniques of indigenous northern Australians to the world. Recently, it’s reinvigorated traditional fire management in Botswana, in southern Africa.
Results so far show the Botswana project is likely to prevent significant amounts of greenhouse gases from entering the atmosphere, reduce destructive fires, promote a productive landscape, increase biodiversity and revive traditional culture.
Australia’s bushfire royal commission is currently looking at how Aboriginal knowledge can be incorporated into mainstream fire management. So let’s take a closer look at how it’s already working in Australia and abroad.

An example of traditional indigenous Australian burning. Warddeken Land Management

Reviving an ancient practice

Intense bushfires devastate ecosystems, biodiversity, human health, livelihoods and economies. Climate change will increase the severity, incidence and intensity of bushfires in many regions.
Over thousands of years, Aboriginal people in Australia have used fire to manage natural resources, and as an integral expression of culture.
Burning was often undertaken in the early dry season, when fires can develop gently and be easily controlled. Such burning removed fuels such as grass and leaf litter that might otherwise cause bigger fires. It also retains the canopy and other plant matter, and so preserves habitat for animals.

Read more: Our land is burning, and western science does not have all the answers

Over time, following the colonisation of Australia, indigenous land managers were forced off or left their traditional lands. Their absence has allowed large and intense bushfires in the late dry season to increase.
Traditional fire management techniques were first reintroduced at scale in Western Arnhem, in the Northern Territory, in 2007. Now there are 76 such projects – more than half either owned by, or significantly involving, an Aboriginal community.
Since the projects began, the total area affected by destructive wildfires has fallen. This reduces emissions because fires caused by cultural burning are less intense and extensive than large wildfires. This reduction is recognised by the federal government as carbon credits, generating more than A$90 million for communities so far.

Ranger Ray Nadjamerrek demonstrates early dry season burning techniques in West Arnhem. Warddeken Land Management

Exporting Indigenous know-how

The initiative focuses on fire-prone savanna landscapes which globally account for more than 60% of carbon emissions from fire each year. Principally funded by the Department of Foreign Affairs and Trade, it comprises an active network of indigenous organisations, traditional owners and experts.
Botswana was the first site to prove that transferring this knowledge is possible. Among the reasons it was chosen were its savanna landscapes and a tradition of fire management by its own indigenous people.
The first ranger exchange took place in May 2019, when Indigenous rangers from Northern Australia travelled to Botswana at the invitation of the Botswanan government.

Read more: A surprising answer to a hot question: controlled burns often fail to slow a bushfire

In savannas outside the town of Maun, Botswanan firefighters pitted their controlled burning skills against Australia’s indigenous rangers.
The Botswanans applied European-style fire suppression techniques they’ve adopted over the years. This involved fire trucks and 30 people. They ignited the windward side of their area, let the fire race through and then extinguished the flames.
It was 38℃, the wind was strong and the bush was dry. It was no surprise the fire was intense and all that remained was a charred landscape.
In contrast, two Australian indigenous rangers used hand-held devices called drip torches to weave a path of fire through their area. Their block was gently burnt using the wind, the bush and their skill – clearing out undergrowth and leaving green-topped trees.

Cultural fire leader Otto Champion from Arafura Swamp Rangers, and Bayo Taylor from Karajarri Rangers, demonstrating cultural burning In Botswana. ISFMI

The demonstration emphatically convinced the 300 spectators, who comprised most of Botswana’s firefighting community, that the skills of Australia’s indigenous rangers were effective in Botswana’s savannas.
Indeed, the techniques used by the visitors are not dissimilar to traditional Botswanan fire methods. The common ground was reflected when the two groups exchanged almost identical fire sticks when the rangers visited a nearby community.
Last year, Botswana sent a delegation to Northern Australia to learn more about the techniques.
At pilot sites in Botswana, the communities, indigenous rangers and local fire managers are now experimenting with reinvigorating traditional fire techniques.

Cultural fire leader Otto Champion from Arafura Swamp Rangers exchanging fire sticks with Oabatsha community leaders. ISFMI

Lessons learnt

The degradation of savanna landscapes in Australia following colonisation is replicated around the world.
Globally, bushfire management is dominated by the concept of fire suppression rather than prevention. Fighting fire with fire seems counter-intuitive to many people. But the Botswana experience shows these attitudes can be changed quickly.
Another key lesson is that convincing people and communities to use traditional fire techniques requires real-life demonstrations. Trying to make the point through lectures, simulations and written material has limited impact.
And creating networks is essential to connect the few experts and limited resources. Knowledge of traditional fire management around the world is scarce, and experience even more so. In Botswana for example, only a few community elders still have this knowledge.

The indigenous Australian rangers quickly convinced Botswanans of the merit in their fire methods. ISFMI

The experiences also show scale is key. A couple of small sites, with a few local people involved, is not enough to manage wildfires effectively.

Beyond Botswana

The initiative has demonstrated how Northern Australia-style traditional fire management will be useful in other savanna environments around the world
We are now working on expanding this Australian technology to other promising sites in Angola, Namibia, Zambia, Zimbabwe, Mozambique, Brazil and Timor Leste.
Many other countries are interested in adopting these techniques. New funding, including from the private sector, is needed to scale up traditional fire management internationally.

Read more: Australia, you have unfinished business. It's time to let our 'fire people' care for this land

The following people made important contributions to this article:
- Nolan Hunter, CEO, Kimberley Land Council
- Dean Munuggullumurr Yibarbuk, Warddeken Land Management
- Rowan Foley, CEO, the Aboriginal Carbon Foundation
- Cissy Gore-Birch, Executive Manager Aboriginal Engagement, Bush Heritage Australia
- Professor Jeremy Russell-Smith, Charles Darwin University
- Professor José M.C. Pereira, University of Lisbon
- Professor Guido van der Werf, Vrije Universiteit
Sam Johnston, Senior Fellow, University of Melbourne
This article is republished from The Conversation under a Creative Commons license. Read the original article.

How investing in green infrastructure can jump-start the post-coronavirus economy

*Investing in natural assets like ponds can help prevent cities from flooding — and save municipalities money. (Shutterstock)*

Michael Drescher, University of Waterloo and Lucas Mollame, University of Waterloo
COVID-19 has turned the world on its head. Many socio-economic benefits Canadians took for granted are now under threat, and the economic, infrastructure and environmental problems that we were once content to ignore are now glaringly obvious.
A recent United Nations report shows that most of Earth’s ecosystems are in serious decline, and this is also true for Canada. In addition, our infrastructure is failing: most of the country’s roads, bridges, stormwater and sewer systems were built just after the Second World War, and up to 40 per cent are close to their expiration dates.
But repairing infrastructure is expensive. Cities own two-thirds of it but receive only eight per cent of all tax dollars and, historically, they have set aside very little money for infrastructure operations, maintenance and rewnewal.
As attentions begin to shift towards economic recovery, some communities are beginning to incorporate natural assets such as lakes, forests or streams into their infrastructure planning while maintaining and improving municipal services such as drinking water supplies, flood protection and stormwater management. Doing so can save municipalities billions of dollars on investments such as water treatment plants.

Economic recovery with natural assets

Natural assets provide benefits to people in the form of ecosystem services like managing stormwater, regulating local climate and filtering pollution. Natural asset approaches do not see people as separate from nature. Instead, they understand that we are part of nature and that nature can support solutions to societal challenges.
As a subset of green infrastructure, natural assets produce societal, environmental and economic benefits. Green infrastructure increases resilience to environmental challenges like climate change, which has emerged as a major threat to cities the world over. In addition, the green infrastructure sector in Ontario alone contributes over $8 billion to our national economy and more than 120,000 jobs.

*A tow truck driver walks back through floodwaters after hooking up a car on the Don Valley Parkway in Toronto in July 2013. THE CANADIAN PRESS/Frank Gunn*

Examples of urban natural asset planning and management can be found in progressive cities across the world. For instance, the latest urban plan for Stockholm, Sweden, has explicitly integrated the city’s natural assets. The plan gives direction to maintain and strengthen green infrastructure like parks and forests. These assets will be important for increasing climate change resilience and protecting the quality of life and health of Stockholm’s residents.
In Ho Chi Minh City, Vietnam, urbanization and climate change combine to increase the frequency of floods and urban heating. These floods damage property, disrupt infrastructure and cause sewer backups, while urban heating increases air pollution and causes heat stress. In response to these threats, the city has developed a climate adaptation strategy that includes plans to expand and strengthen the city’s green spaces to increase water storage capacity and reduce urban heating.

Read more: How cities can add accessible green space in a post-coronavirus world

In Canada, the town of Gibsons, B.C., has incorporated the local pond system into their municipal asset management plan. The ponds function as a stormwater system that stores, cleans and filters water that would otherwise require storm sewers, bypass pipes and other forms of engineered infrastructure at a cost of $3.5 million to $4 million. An important additional benefit is that natural assets can help fight climate change by capturing carbon.
The Municipal Natural Assets Initiative, which works with local governments to account for and manage their natural assets, has partnered with Gibsons on its stormwater management study. It is now scaling up that example for other communities across Canada, and is helping address some of the barriers that local governments face in managing their natural assets. Investments into natural assets could help municipalities that are stretched thin due to higher spending and lower revenues from COVID-19.

Maximizing economic stimulus spending

One of the best practices of disaster management is “building back better” to increase resilience in the community and the rest of the country. This includes investments in services and infrastructure. Natural asset strategies such as reforestation initiatives can contribute to generating the needed economic stimulus for recovery efforts. Nature-based solutions that support vital ecosystem services can reduce the financial costs of climate change, contribute to job creation, increase resilience and reduce poverty.
In late April, data from the Federation of Canadian Municipalities showed that Canadian communities faced $10 billion to $15 billion in near-term, non-recoverable losses from lost property taxes, utility charges and decreased transit ridership, and called for at least $10 billion in emergency operation funds from the federal government. So far, the federal government has only committed to release the annual Gas Tax Fund funding to municipalities as an early, one-time transfer of $2.2-billion.

*Extensive forests line the Don River Valley Park with the Prince Edward Viaduct and Toronto skyline in the background. (Jess/Wikimedia Commons), CC BY-SA*

The country needs additional investments. The 50 Million Tree Program might be an example of a great target for this. After the Ontario government pulled the funding for this program, the federal government stepped in and guaranteed funding until 2023. Planting urban trees is as close as it gets to a magic bullet in our fight against climate change and air pollution. Expanding the 50 Million Tree Program and continuing it past 2023 would be a great investment with short and long-term economic benefits.
A portion of any federal or provincial stimulus investments should be used to support natural assets and green infrastructure projects that protect ecosystems, improve municipal service delivery, produce jobs and strengthen the economy. Doing so could save municipalities millions — if not billions — of dollars in infrastructure service costs.
Let’s not lose out on this opportunity to make our municipalities more resilient to the future threats that we know will come.
The authors thank Roy Brooke and Cheekwan Ho for their contributions to this commentary.
Michael Drescher, Associate professor, School of Planning, University of Waterloo and Lucas Mollame, Master's Candidate, School of Planning in the Faculty of Environment, University of Waterloo
This article is republished from The Conversation under a Creative Commons license. Read the original article.

'Like having a truck idling in your living room': the toxic cost of wood-fired heaters

WOOD BURNING HOME HEATING IS USED IN THE AMERICAN PACIFIC NORTHWEST STATES

Peter Irga, University of Technology Sydney; Brian Oliver, University of Technology Sydney, and Fraser R Torpy, University of Technology Sydney
Australians are accustomed to having fresh air, and our clean atmosphere is a source of pride for many.
Last summer’s bushfires, however, brought air quality to the public’s attention, as millions of Australians breathed some of the world’s worst quality air.
But there’s a lesser-known source of pollution causing billions of dollars worth of health costs every year: indoor wood-fired heaters.
This week, the Victorian branch of the Australian Medical Association endorsed calls to remove these heaters via a buyback or subsidy scheme. But will it work?

Read more: How does poor air quality from bushfire smoke affect our health?

Wood heater smoke is a huge pollution source

In winter, wood heater smoke is the single biggest air pollutant in New South Wales and the ACT. Similarly, in Victoria, wood smoke on cool winter days is responsible for most breaches of air quality standards.
Wood heater smoke is generated from both open fireplaces and wood-fired heaters. Wood-fired heaters are controlled-combustion, domestic heating appliances. In order to discharge emissions, they use a metal pipe called a flue, while open fireplaces use chimneys.
Around 10% of Australian households – roughly 900,000 homes – use wood as their main source of heating, according to the ABS.

Read more: Bushfire smoke is everywhere in our cities. Here's exactly what you are inhaling

Based on NSW guidelines, burning 10 kilograms of wood (an average day) in a modern, low-emitting wood heater can produce around 15 grams of “particulate matter”.
This is composed of tiny particles which can penetrate into the respiratory system, potentially causing lung and heart diseases. It is one of the most dangerous components of smoke, and a carrier for many of its cancer-causing chemicals.
By contrast, a truck travelling on congested urban roads can produce just 0.03 grams of particulate matter per kilometre travelled. A truck would therefore have to travel 500km in heavy traffic – roughly the distance from Melbourne to Mildura – to produce the same particulate matter emissions as one average day of using a wood heater.
So a wood-fired heater is like having a truck idling in your living room all day (albeit with the bulk of the emissions escaping via the chimney).

Smoke is toxic

The smoke from wood fires is very similar to that generated by bushfires, and is also detrimental to our health.
Australia’s wood-fired heaters are estimated to cause health costs of around A$3,800 per wood heater each year.
Given the roughly 900,000 wood heaters used as primary household heating sources in Australia, this could be as high as A$3.4 billion annually across the country.
One study published in May estimated 69 deaths, 86 hospital admissions, and 15 asthma emergency department visits in Tasmania were attributable to biomass smoke each year – the smoke which comes from burning wood, crops and manure. More than 74% of these impacts were attributed to wood heater smoke, with average associated yearly costs of A$293 million.
Another study modelled the effects of air pollution on over-45-year-olds in Sydney over seven years. It found chronic exposure to low levels of particulate matter was linked with an increased risk of death. Depending on the model used, it found between a 3-16% increased risk of dying occurred with each extra microgram (one millionth of a gram) of particulate matter per cubic metre of air.

Read more: From face masks to air purifiers: what actually works to protect us from bushfire smoke?

All of this assumes wood heater users follow the law and use clean, dry hardwood as fuel. Problems become far worse when treated wood is used as the fuel source.
Treated timber offcuts from construction or demolition activities are freely available and therefore continue to be used as fuel for wood heaters, against recommendations.
Much of this timber is treated with an antifungal chemical called copper chrome arsenate. Breathing the emissions when this wood is burned can increase incidents of liver, bladder, and lung cancers, and reduce the production of red and white blood cells, leading to fatigue, abnormal heart rhythm, and blood-vessel damage.
There is no safe level of indoor or outdoor air pollution. This is an ideal time to consider the hidden dangers associated with our “clean” air.

Wood heater smoke has been linked with increased hospitalisations and deaths from asthma. www.shutterstock.com

Change is difficult

Standard testing for new stoves is one way authorities try to reduce wood smoke emissions. Australian heaters must be designed to pass strict standards, however this system may not reflect the way heaters are actually operated in the home environment, because this varies so much between households.
For example, in New Zealand, testing on five heaters installed in people’s homes recorded particulate matter levels more than 15 times higher than their predicted average calculated during testing.
Banning wood stoves altogether is inequitable, as some people cannot afford any other source of heating, and many people employed in the wood-fire heater industry could lose their jobs. But changing economic incentives could work. An intervention method currently being proposed in Victoria is a wood stove buyback or subsidy scheme, which is now supported by the Victorian branch of the Australian Medical Association.
However, a similar rebate scheme did not have much impact in Canberra. Since November 2015, residents have been able to claim a subsidy of up to A$1,250 if they replace their wood heater with a ducted electric reverse cycle system. Just five households took up this rebate in the first six months. Meanwhile, 40,000-50,000 wood heaters are sold in Australia each year.
Another option is fines. Tasmanians can be fined A$1,680 if their chimney emits smoke which is visible for more than ten minutes. However, when these regulations were announced the laws were considered by many Tasmanians to be heavy-handed and the government was met with community resistance.

Many attempts at reducing the number of indoor wood heaters in Australia have been ineffective. www.shutterstock.com

A way forward?

In 2001, Launceston established several strategies to encourage use of electric heaters instead of wood heaters, including a grant of A$500 to those switching over.
Following this, wood heater prevalence fell from 66% to 30% of all households, corresponding to a 40% reduction in particulate air pollution during winter.
Education could also help. If people knew the concentrations of air pollutants in their homes, they might be motivated to change their wood burning behaviour. Often residents are unaware of the concentrations of smoke generated by their activity, with many considering opening a window reduces the level of wood smoke in their home. Controlling indoor pollution is difficult, especially if the major source of the pollution is outdoors – opening the window would actually let more pollution in.
We suggest that together with the proposed rebate schemes, one way forward could be to provide affordable access (through subsidies or otherwise) to air-quality sensors. At the lower end of the scale, prices range from A$100-500, with more accurate devices in the range of A$1,000-5,000.
Despite the expense, they can improve awareness of levels of air pollution among those with wood-fired heaters, and may provide the impetus for people to work together and change community perceptions around wood-burning appliances.

Read more: How does bushfire smoke affect our health? 6 things you need to know

This article is supported by the Judith Neilson Institute for Journalism and Ideas.
Peter Irga, Chancellor's Postdoctoral Research Fellow and Lecturer in Air and Noise Pollution, School of Civil and Environmental Engineering, University of Technology Sydney; Brian Oliver, Research Leader in Respiratory cellular and molecular biology at the Woolcock Institute of Medical Research and Professor, Faculty of Science, University of Technology Sydney, and Fraser R Torpy, Director, Plants and Environmental Quality Research Group, University of Technology Sydney
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Girls score the same in maths and science as boys, but higher in arts – this may be why they are less likely to pick STEM careers

THE SEPARATION OF ART FROM SCIENCE WAS THE TRANSITION FROM ALCHEMY TO CHEMISTRY

Silvia Griselda, University of Melbourne and Rigissa Megalokonomou, The University of Queensland
Last month, the Australian Academy of Science published a report showing the COVID-19 pandemic would disproportionately affect women in the STEM (science, technology, engineering and maths) disciplines.
The report noted before COVID-19, around 7,500 women were employed in STEM research fields in Australia in 2017, compared to around 18,400 men. The authors wrote:

The pandemic appears to be compounding pre-existing gender disparity; women are under-represented across the STEM workforce, and weighted in roles that are typically less senior and less secure. Job loss at a greater rate than for men is now an immediate threat for many women in Australia’s STEM workforce, potentially reversing equity gains of recent years.

Women are less likely to enrol in science and maths degrees than men. In Australia, only 35% of STEM university degrees are awarded to women. This figure has been stable over the past five years.
Some research in the 1990s suggested girls don’t study maths and science because they might not do as well as boys. But recent research shows girls score similarly or slightly higher than boys in maths and science.
So why don’t they choose these careers as often as men?
Our recently published study found while women perform at the same or higher level in maths and science as men, their performance in the humanities is markedly better. This may be the reason they’re choosing not to pursue STEM careers.

Girls just as good at maths and science

We wanted to see if there were gender differences in school performance when it came to science and maths and whether these affected students’ university applications.
Our study used data of more than 70,000 secondary school students in Greece over ten years.
We found girls’ scores in maths and science were around 4% higher than boys. But their scores in humanities subjects were around 13% higher.
We also found girls were 34% less likely to chose a STEM-related specialisation in their last years of high school.
These findings can be translated to Australia. According to the latest results from the OECD’s Programme for International Student Assessment (PISA), girls in Australia perform on a similar level to boys in maths and science, but at a much higher level in reading.
The difference between girls’ and boys’ performance in reading is 6% in Australia and 9% in Greece.
But when it comes to maths and science, there is not much of a difference between girls’ and boys’ performance in either country.

Female comparative advantage in STEM

Our study showed students decided which fields they want to specialise in by comparing their academic strengths and weaknesses between subjects and with their classmates.
Using our data, we compared the students’ grades in STEM and humanities subjects. If a student had a higher grade in STEM than reading and writing subjects, we defined this student as having a STEM advantage. If this STEM advantage was greater than one of the students’ classmates, this student had STEM as an academic strength.
Because boys were generally better in science and maths than humanities, they had a higher STEM advantage. As girls were only slightly better in science and maths than humanities, their STEM advantage was lower than that of boys.
In our data, we considered pairs of girls with identical grades in STEM and humanities subjects at the beginning of secondary schools, who were randomly assigned to different classrooms. We then observed their enrolment decisions one to three years later.
For instance, two girls with a similar performance in STEM and humanities (with same STEM advantage) were assigned to different classrooms.
One girl was assigned to a classroom where her classmates had a high STEM advantage (higher scores in STEM than humanities). The other girl was assigned to a classroom where her classmates had a similar performance in STEM and humanities subject (no STEM advantage).
Our findings showed these two girls, on average, even if they had identical grades in STEM and humanities, chose different fields of study at the end of secondary school. The former (whose peers had a STEM advantage) was less likely to choose a STEM-related field.
Our study showed these two girls with identical performance ended up choosing a different educational career, based on which classmates they sat with.
This explained up to 12% of the gender gap in STEM enrolment in tertiary education.
We did the same for boys. Analysing pairs of boys with identical grades but different classmates, we did not observe any difference in their enrolment decisions.

What can be done?

Our research indicates girls are more influenced by their success relative to their peers, whereas this does not hold for boys.
Our findings are in line with previous research that suggests girls are more influenced by negative grades than boys, especially in STEM, when making decisions about their future.
Our research suggests the teacher has an important role to play in recognising and encouraging individual academic strengths, independently of classmates or gender.
Previous research has shown teacher gender stereotypes regarding girls’ ability in STEM negatively affects the way girls see themselves.
Teachers can and must foster confidence in girls when it comes to science and maths subjects, even if they may be better at reading and writing.
Maths and science studies lead to occupations such as engineering, physics, data science and computer programming, which are in great demand and generally pay a high salary. So turning away from STEM may have a long lasting impact on girls’ life earnings.
Silvia Griselda, PhD student, University of Melbourne and Rigissa Megalokonomou, Lecturer in Economics, The University of Queensland
This article is republished from The Conversation under a Creative Commons license. Read the original article.

Earth's rock-solid connections between Canada and Australia contain clues about the origin of life

Half Dome in California is constituted from granite, a relatively less dense type of rock. (Shutterstock)

Joshua Davies, Université du Québec à Montréal (UQAM) and Jesse Reimink, Pennsylvania State University
The rocks at the surface of the modern Earth are broadly divided into two types: felsic and mafic. Felsic rocks are generally relatively low density — for a rock — and light in colour because they are made from whitish minerals rich in silicon and aluminium. Half Dome in California is made of granite that is a felsic rock. Mafic rocks, in contrast, are relatively high in density and dark in colour because they contain minerals rich in iron and magnesium; Giants Causeway in Northern Ireland is made of basalt, which is a mafic rock.
The difference in density between felsic and mafic rocks means that felsic rocks are more buoyant, and therefore sit at higher elevations above the Earth’s mantle (the layer inside the Earth between the crust and the core). For this reason, felsic rocks make up Earth’s continents whereas the lower elevation crust under the oceans is mafic.
The mechanisms that separated the rocks at Earth’s surface into these two groups may have also created the environment needed for life to flourish 4.3 billion years ago, very early in the history of Earth.

The Giants Causeway in Northern Ireland is an unusual rock formation comprising mafic rocks. (Shutterstock)

The separation into these two rock types is the result of plate tectonics: where the tectonic plates separate and move apart, the rocks below become depressurized, melt and fill in the gap between them, like the Mid-Atlantic Ridge. The rock that fills the gap between the plates is mafic.
When one plate slides below another, fluids released from the lower plate cause melting in the mantle. These melts have to pass through the upper plate to reach the surface. On their way to the surface, they undergo a series of processes called fractional crystalization, which can change mafic melts into felsic melts.

Establishing timelines

When this separation happened is a matter of great debate in the Earth sciences because it may allow us to determine when the Earth became habitable for life. Many Earth scientists believe that the weathering of continental crust may have provided the nutrients for life to thrive; identifying when the first continents formed indicates when this may have occurred.
Earth scientists also debate whether plate tectonic processes in the past were the same as those occurring today, and whether they were even needed to form continental crust in the past. The first continental crust may have been formed through the interaction of oceanic crust and mantle plumes of heat coming from the Earth’s core. Another theory suggests that continental crust formed through meteorite bombardment.
The exact mechanism is important for understanding the history and evolution of Earth, and may help understand the processes that could be occurring on other planets.

Reviewing the records

Our recent study looked at the oldest geological material on Earth. The results suggest that Earth was already separating into these two rock types by 4.3 billion years ago — effectively since the beginning of the Earth’s geological record. Our data also gave intriguing insights into the tectonic processes that may have been occurring at that time.
The origin of continental crust is debated in part because the further back in time you go, the fewer rocks there are to study. Samples from the Acasta Gneiss Complex in northern Canada were found to be about four billion years old — the oldest known rocks on Earth. These Acasta Gneiss rocks are felsic and composed of tonalite-trondhjemite-granodiorite.
There are very few older samples from Earth, the most famous of which is the Jack Hills zircons. These are up to 4.3 billion years old, 300 million years older than the Acasta Gneiss. They are tiny grains of mineral zircon that have been eroded out of their parental rock (the rock in which they initially crystallized).
These zircons are found in much younger sediments in Australia, which means that it’s difficult to determine what kind of rocks these minerals originally came from, leaving open the question of whether there was continental crust during the earliest period of Earth’s history.

Continental connections

In our recent study, we compared all aspects of the chemistry of the zircon crystals from Acasta rocks to the Jack Hills zircons to see if they could have been formed in a similar environment.

A contrast-enhanced true colour satellite image (Landsat 5) of the Jack Hills in Western Australia. (Gretarsson), CC BY

We found that the two sets of zircon grains are chemically identical, suggesting that they formed from the same kinds of rocks and likely in the same kinds of tectonic settings. This means that the Earth may have started to create continental-type crust very soon after it formed.
The chemical composition of both suites of zircon crystals also suggest that they grew in magmas that originated at great depth in the Earth. Deep origins for magmas are a typical sign of subduction on the modern Earth.
We compared the amount of uranium in the crystals to the amount of ytterbium, a rare element. When a magma forms at great depth, the mineral garnet is often present, which gathers ytterbium. This means less ytterbium is taken up by zircon crystals, suggesting that a relative lack of ytterbium indicates that these magmas formed in deep environments.
The Jack Hills zircons are known to have crystallized at relatively low temperatures. We found that the temperatures from Acasta zircons matched exactly with the Jack Hills zircons, further indicating their similarity.

Finding the beginning

Ultimately, our results indicate that the tectonic processes occurring at the beginning of the geological record may not have been so different from the processes occurring afterwards. Evidence that things were not too different to modern Earth brings intriguing insights into the potential for the origin of life and the habitability of the early Earth, possibly confirming that life was present very early in Earth’s history.
This is a corrected version of a story originally published on June 17, 2020. The earlier story said 4.3 million years ago instead of 4.3 billion years ago.
Joshua Davies, Professor, Sciences de la Terre et de l'atmosphère, Université du Québec à Montréal (UQAM) and Jesse Reimink, Assistant Professor of Geosciences, Pennsylvania State University
This article is republished from The Conversation under a Creative Commons license. Read the original article.

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