It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Friday, November 26, 2021
Warnings may reduce hate speech on Twitter, new study finds
Warning Twitter users about potential adverse consequences of their use of hate speech can decrease their subsequent posting of hateful language for a week, finds a new study by New York University's Center for Social Media and Politics.
"Debates over the effectiveness of social media account suspensions and bans on abusive users abound, but we know little about the impact of either warning a user of suspending an account or of outright suspensions in order to reduce hate speech," explains Mustafa Mikdat Yildirim, an NYU doctoral candidate and the lead author of the paper, which appears in the journal Perspectives on Politics. "Even though the impact of warnings is temporary, the research nonetheless provides a potential path forward for platforms seeking to reduce the use of hateful language by users."
In the aftermath of decisions by Twitter and other social media platforms to suspend large numbers of accounts, in particular those of former President Donald Trump following the Jan. 6, 2021 attack on the U.S. Capitol, many have asked about the effectiveness of measures aimed at curbing hate speech and other messages that may incite violence.
In the Perspectives on Politics paper, the researchers examined one approach—issuing warnings of possible suspensions resulting from the use of hate speech—to determine its efficacy in diminishing future use of this type of language.
To do so, the paper's authors designed a series of experiments aimed at instilling the possible consequences of the use of hate and related speech.
"To effectively convey a warning message to its target, the message needs to make the target aware of the consequences of their behavior and also make them believe that these consequences will be administered," they write.
In constructing their experiments, the authors focused on the followers of users whose accounts had been suspended for posting tweets that used hateful language in order to find a group of users for whom they could create credible warning messages. The researchers reasoned that the followers of those who had been suspended and who also used hateful language might consider themselves potential "suspension candidates" once they learned someone they followed had been suspended—and therefore be potentially willing to moderate their behavior following a warning.
To identify such candidates, the team downloaded more than 600,000 tweets on July 21, 2020 that were posted in the week prior and that contained at least one word from hateful language dictionaries used in previous research. During the period, Twitter was flooded by hateful tweets against both the Asian and Black communities due to the coronavirus pandemic and Black Lives Matter protests.
From this group of users of hateful language, the researchers obtained a sample of approximately 4,300 followers of users who had been suspended by Twitter during this period (i.e., "suspension candidates").
These followers were divided into six treatment groups and one control group. The researchers tweeted one of six possible warning messages to these users, all prefaced with this sentence: "The user [@account] you follow was suspended, and I suspect that this was because of hateful language." It was followed by different types of warnings, ranging from "If you continue to use hate speech, you might get suspended temporarily" to "If you continue to use hate speech, you might lose your posts, friends and followers, and not get your account back." The control group did not receive any messages.
Overall, the users who received these warning messages reduced the ratio of tweets containing hateful language by up to 10 percent a week later (there was no significant reduction among those in the control group). And, in cases in which the messaging to users was more politely phrased ("I understand that you have every right to express yourself but please keep in mind that using hate speech can get you suspended."), the decline reached 15 to 20 percent. (Based on previous scholarship, the authors concluded that respectful and polite language would be more likely to be seen as legitimate.) However, the impact of the warnings dissipated a month later.
The paper's other authors were Joshua A. Tucker and Jonathan Nagler, professors in NYU's Department of Politics, and Richard Bonneau, a professor in NYU's Department of Biology and Courant Institute of Mathematical Sciences. Tucker, Nagler, and Bonneau are co-directors of the NYU Center for Social Media and Politics, where Yildirim conducts research as a Ph.D. candidate.Twitter tests Safety Mode to block internet trolls
Increasing use of staff surveillance by employers during the COVID-19 pandemic endangers trust in the workplace, according to a major new report by the University of St Andrews.
The study, for the European Commission's Joint Research Council, also warns employers not to sacrifice ethics for the sake of efficiency as it can backfire leading to mental health issues, productivity decline and staff resignations.
Webcam photographs, recording keystrokes and movement trackers have all been increasingly used by employers as millions of workers were forced to work from home in 2020.
The demand for employee monitoring software increased by 108 percent in April 2020, according to the major review of research literature on workplace surveillance from the past four decades.
Author Professor Kirstie Ball, of the School of Management at the University of St Andrews, said: "There is a clear need for trust to be rebuilt in the workplace between staff and employers post-COVID.
"Where monitoring has a specific purpose such as health and safety, it can actually reassure staff. Or in development and training it can provide valuable feedback.
"However, it can also have negative impacts too. A heavy focus on monitoring the quantity of output can reduce work quality.
"Where there is no explicit purpose for the monitoring, and information is collected for its own sake, negative attitudes can result including: perceptions of decreased fairness and justice, decreased satisfaction, increased stress and a decline in trust."
Excessive monitoring, according to the report, can be considered by staff as demonstrating a lack of confidence or belief in employees. Low trust in the workplace can then cause a vicious cycle.
Professor Ball said: "Employers impose punitive surveillance which causes the behaviors it was put in place to prevent, as employees try to resist or avoid it. The social support provided by managers for monitored workers is crucial to avoid some of these negative outcomes."
The report also notes that there is a danger of low managerial support for monitored employees.
Professor Ball added: "There is a real need for more research on how data is used by employers and policy may need to change to reflect these new ways of working."
Certain broadcasters and social media celebrities openly promote fake facts or misrepresentations of science and data to their audience, many of whom do not seem to care whether they are right or wrong, as long as they are hearing what they want to hear.
The promotion of misinformation can be caused by an over-inflated belief in their own judgment and knowledge, or often, they simply relish the chance to proclaim their own contrarian or ideological views. Sometimes, it's just about self-interest.
Many of us have at least a few controversial beliefs. We might believe that the death penalty deters crime, or that raising the minimum wage decreases unemployment, or that raising business taxes will reduce innovation.
We might even believe that women are not as good at maths as men, or that the Earth is flat.
Some of these beliefs we will hold strongly.
But when we attempt to justify our beliefs, we often find the evidence pool is very shallow.
Researchers have identified a chronic illusion of explanatory depth, in that we overestimate our understanding of the world.
We can discover this by trying to justify our pet beliefs. To illustrate, when I interrogate myself about why I believe the death penalty is not a deterrent, I find there is not a lot there except for consensus beliefs among my peer group—some of whom I hope have looked into the evidence—some intuition, and vague memories of looking at some blog posts or newspaper articles. This is not a lot. But it is perhaps not surprising: we simply don't have time to be experts on everything.
Sometimes people are described as having fallen prey to the Dunning-Kruger effect, or even as "having" Dunning-Kruger. Donald Trump was one such person.
The Dunning-Kruger effect, however, is a population-level effect, so no individual can "have" it. It primarily means that just because someone is confident doesn't mean they are right. In fact, there are individual differences in confidence, with some people being absurdly sure of themselves, and others quite diffident.
But the confidence of highly confident but wrong people comes not from their ignorance, but from the fact that they are inherently confident about everything. Some researchers have described it as arrogance.
If he knew more, would Trump have been less confident? I doubt it; Trump was (or is) simply full of bluster, and his confidence was simply unrelated to his knowledge.
What determines the beliefs we adopt when we have a choice?
Scientific evidence can help, but often we believe what we want to believe anyway.
These beliefs might be "chosen" through indoctrination. They might be the result of self-interest or strongly held ideology, such as wealthy people believing taxes rob people of initiative. Or they might be required to fit into a social group.
How do specific beliefs become linked to specific social groups? In some cases, the link is quite clearly defined.
Strongly religious people generally do not believe in evolution, and atheists are not creationists. Partisanship also produces dispositions to belief. The moral values of conservatives involve different issues—such as respect for authority—than those on the left, who put more weight on harm prevention. Liberals tend to be more drawn to seeking out change and novelty, both personally and politically, while conservatives, in contrast, have a stronger preference for things that are familiar, stable and predictable.
Many current controversies have this flavor, such as whether COVID vaccines or masks should be required, or whether nuclear power is good for the environment. We look to our peers, and to the authorities and ideologies we respect, and follow their lead.
We are also more likely to follow those who are highly confident, even though confidence is a poor predictor of accuracy. And, of course, those we follow, being human just like us, are probably doing the same thing.
Armchair experts are just behaving normally
Let's return to those high-profile broadcasters, social media celebrities and armchair experts who have been wilfully spreading an avalanche of misinformation.
They are really no different from everyone else.
If it is natural to believe things based on little evidence, and to believe things because they fit with our social group and partisan preferences, it should not surprise us that some hold beliefs quite at variance with ours. Or that they apparently do so despite, as it appears to us, overwhelming contradictory evidence—from their perspective we are doing the same thing. We should not be surprised if a TV reporter or Twitter celebrity is just as likely as anyone else to believe things based on flimsy evidence.
As individuals, we may have fallen on the side of accepted scientific wisdom (where the bulk of the evidence and experts sit) during the pandemic, but there will probably be other situations where we too have beliefs that are based on our own misjudgements, ideologies or personal gain.
The American writer and political activist Upton Sinclair famously wrote: "It is difficult to get a man to understand something, when his salary depends upon his not understanding it!".
Even a scientist, when hired directly by a pharmaceutical company to evaluate the efficacy of a new blockbuster drug, might be disposed to find evidence of the drug's effectiveness.
Conversely, there are probably reasons why a small—but prominent—number of scientists have taken a distinctly outlier stance regarding the pandemic, or other issues, such as climate change.
We need go no further than this to understand why there will be armchair experts proposing all possible positions, and when they gain attention and celebrity for doing so, they will stick with those positions.
To give up their position will be to lose all the attention, all the celebrity, and all their credibility. Imagine what would happen to Donald Trump if he were to come down on the side of poor refugees. Imagine what would happen to the radio hosts who have built up a larger following based on their unwavering libertarian views if they suddenly declared they had changed their minds about masks.
Once committed to a set of beliefs, the armchair expert is in it for the long run.
Legislation that enforces a 'cooling off' period between purchasing and acquiring a firearm reduces impulse purchases. It also limits the number of homicides, especially in the domestic sphere. This is demonstrated by behavioral economist David Schindler of Tilburg University on the basis of a quantitative study in various U.S. States. The publication will appear in the journal Review of Economics and Statistics.
Peak in weapon purchases
Schindler and his coauthor Christoph Koenig examined a six-month period in 2012 and 2013, when gun sales in the United States soared to unprecedented heights. The spike was caused by a dramatic shooting incident at Sandy Hook Elementary School and the re-election of president Barack Obama. As a result of these events, many Americans expected stricter gun laws. To get ahead of these, they pre-emptively bought guns. In 35 of the U.S. states, these guns are sold directly over the counter, but in 15 other states, a delay has been deliberately built in between purchasing the gun and actually getting hold of it. This 'cooling off period' varies from two days to six months.
Impulsive buyers are deterred
Over a period of six months, the Tilburg researcher compared Google searches for firearm-related expressions, registered background checks for gun sales, and homicides across the United States. He found that there was equal interest in purchasing firearms in states with delay laws as in states without such laws, but that fewer weapons were eventually sold. This effect is visible with both a brief and a longer cooling-off period.These results led Schindler to believe that people who are prone to impulsive behavior postpone their gun purchase; for them it is less attractive to surrender money now, but only receive a gun in the future.
Fewer women killed at home
In addition to fewer arms purchases, delay laws also lead to fewer murders. Schindler found that states with delay laws had 2 percent fewer handgun-related homicides than states without delay laws. This means that in the period under review, in the 35 states without delay laws, about 200 murders could have been prevented if such laws had been in place. Victims of these 'extra' murders are mostly middle-aged women who were killed in their own homes after an argument. The results suggest that impulsive gun purchases can result in domestic violence, which delay laws have a somewhat dampening effect on.
Way out of the political deadlock
Schindler's research supports a conclusion from previous research: more guns lead to more murders. It also suggests a way out of a political deadlock in the United States: legislation that enforces a cooling-off period between purchase and possession of firearms limits the number of homicides without infringing on the right to bear arms, which is cherished by many in the U.S.
More information:Christoph Koenig et al, Impulse Purchases, Gun Ownership, and Homicides: Evidence from a Firearm Demand Shock,The Review of Economics and Statistics(2021).DOI: 10.1162/rest_a_01106
A survey conducted by a team of researchers from The University of New Mexico finds that students who are food-insecure are more likely to fail or withdraw from classes or drop out of college entirely.
The survey was done by lead author Heather Mechler, UNM Office of Institutional Analytics; Kathryn Coakley, UNM Department of Individual, Family, and Community Education; co-PI Marygold Walsh-Dilley, Department of Geography; and co-PI Sarita Cargas, Honors College.
Their findings were recently published in the Journal of College Student Retention: Research, Theory & Practice in an article titled "Examining the Relationship Between Food Insecurity and Academic Performance: Implications for Diversity and Equity in Higher Education."
This article is an outcome of the larger UNM Basic Needs Project, which is co-led by Cargas and Walsh-Dilley. Mechler is a critical part of the team since students are surveyed through her office and she also is able to link survey responses to student academic outcomes. Coakley brings expertise on nutrition and public health, and is especially helpful for survey design and data analysis. Cargas is an important liaison with UNM administration and with policymakers, and works to develop solutions. Walsh-Dilley leads the qualitative data collection efforts and is involved in data analysis.
This study shows that foodinsecurity is a strong impediment to some students' ability to succeed academically, Mechler emphasized.
"When you are not eating enough and you are experiencing anxiety about how you're going to afford to feed yourself, you don't have much energy or focus left to devote to studying and going to class. Our analysis showed that if you have two students from the same background with the same personal characteristics, where one student is food secure and the other food insecure, the student who is experiencing food insecurity is twice as likely to leave college and over one-and-a-half times as likely to fail or withdraw from a course," Mechler observed.
Attaining a college degree can lead to many opportunities for a better, healthier, and more fulfilling life, she continued, adding, "However, it is disheartening that some students are locked out of these opportunities because they lack stable access to affordable nutrition."
The study is unique in that they included students pursuing graduate and professional degrees in the survey. Most of the research on food insecurity in higher education focuses on undergraduate students, but a significant number of students in these higher-level programs struggle with food insecurity.
"For the most part, there is a lower prevalence of food insecurity in graduate and professional students compared to undergraduate students, but it was higher than we had anticipated," Mechler noted.
"This research is really important because it helps to address educational inequality. Our research finds that the students most affected by food and housing insecurity are minority students, LGBTQ+ students, international students, student parents or those providing care for dependents," Walsh-Dilley said. "When students struggle to satisfy their basic needs, they are already at a disadvantage and are less likely to be successful academically. This is how inequality becomes reproduced over and over again. But, if we can support low-income students so that they are successful through college, then maybe we can break that cycle."
In the students' own words
Many students spoke about the stress they experience due to food or housing insecurity.
"I had never been that food insecure and the stress of… it's not just stress, it's like panic. I don't know where I'm going to live after these three months. I hope this job works out. I don't have money for food. Like yeah, panic. Being able to focus on school and being able to focus on my kids and be emotionally and mentally present for them was, in my experience… I mean, it was very difficult. It just saps all of your attention. It takes all of your mental energy."
"[Basic needs insecurity] impacts greatly in terms of stress. I mean, it's hard to study when you are like OK, when is the next shoe going to drop? Let's leave it at that. I don't want to sound too depressing but it is a major impact… So, that has a huge impact on studying and on being able to concentrate and wondering which shoe is going to drop. So, that's a big one."
Students often spoke about how the stress and anxiety of food and housing insecurity impacted their academic success.
"I mean, definitely it's a source of anxiety, right? It's a source of stress. It's a source of constant worry. I know for me, I don't perform very well academically or just living life if I'm under constant stress or constant anxiety… During that semester where I had to really be aware of how I was spending my money, it was a tough semester. I think I dropped down to just two classes or like six credit hours. I don't even think I did very well in one of them. So, I think I took one of them for credit/no credit. So yeah, I mean just a constant source of anxiety. That's definitely going to have an effect on your performance in terms of school and in terms of your mental health and your physical health and your relationships with friends or family. So yeah, it's not going to have a positive impact. That's for sure."
"I had to drop out of college the first time due to the insecurities."
One student summed it up thus:
"I mean, it's kind of hard to study when you are hungry."
The research continues. Mechler said they conducted another survey in April 2021, and are holding focus groups with students this Fall semester to learn more about how students experience food and housing insecurity.
"Our plan is to survey students each year, perhaps including other institutions in New Mexico to get more insight into how food insecurity differs by student population and location of the institution. We want to bring more understanding and awareness to the issue of college student food insecurity so that leaders and policy makers can address it," she said.
What can be done to help?
Many things can be done to help food insecure students. To start, Mechler said, faculty members can add language to their syllabi about resources available to students who need support with food, housing, and other necessities of life.
"Just mentioning it can normalize the act of getting assistance, and can help destigmatize the experience of food insecurity. Many students who are food insecure don't realize that there's a term for what they're going through, and may feel ashamed that they don't have the resources to go out with friends for a meal, grab a coffee before class, or buy sufficient groceries. By putting a name to an experience, you can help someone feel less alone," she noted.
Staff members can keep a list of resources at UNM and in the broader community that can help students find supplemental food, assistance with SNAP (food stamps) applications, and other supports.
"Navigating many of these systems can be intimidating, so having a trusted ally guiding you can make all the difference," Mechler observed.
Also, students can engage in research, class projects, or service learning opportunities that explore why people experience food insecurity, structural barriers that prevent people from getting help, and how they can change systems and processes to make sure everyone has access to the things they need. Mechler advised that students can help struggling friends or classmates by urging them to visit the Lobo Food Pantry or another food pantry and go with them to show support. Also, volunteers are needed to help operate the pantry, organize shelves, or stock incoming items.
Everyone can donate to the Lobo Food Pantry with financial contributions, she added, or by donating shelf-stable food, hygiene, and toiletry items directly to the pantry. The Lobo Food Pantry is open to all UNM students, regardless of financial need, and is open for a few hours every day during the week.
"The Dean of Students and the staff with LoboRespect have really done a fantastic job in securing resources for the pantry and being responsive to student needs. They are adding a refrigerator soon, which will expand the types of foods that they can offer. This is an extremely worthy cause to support with your time and resources," Mechler said. "It's inspiring to see how much good can result when people care about others and commit to helping them. Through this project, I have met people from all over the UNM community who are doing great work in this area. They all truly believe that every student deserves the chance to succeed."
The team will continue to work on this project, collecting data to see how these trends shift over time, and using these data to raise awareness and encourage the university and local and state policy makers to support food and housing security among students, Walsh-Dilley said, adding that several other manuscripts are under review and they are developing additional research about how to intervene to support students and how to extend this type of data collection at other New Mexico institutions.
"These findings make clear that food and housing insecurity significantly impacts student academic success," Walsh-Dilley said. "Access to food and housing are matters of educational inclusion and equity and we need to prioritize student basic needs if we care about addressing inequality among our students and our state."Food insecurity during college years linked to lower graduation rate
More information:Heather Mechler et al, Examining the Relationship Between Food Insecurity and Academic Performance: Implications for Diversity and Equity in Higher Education,Journal of College Student Retention: Research, Theory & Practice(2021).DOI: 10.1177/15210251211053863
While the causes are many—environmental degradation, socioeconomic inequality, systemic and regulatory barriers, and more—the fact remains that healthy and traditional foods are in short supply in Canada's First Nations communities, according to the study.
Its findings, along with with recommendations for decision-makers, were released Oct. 21.
We asked Malek Batal, a professor in the nutrition department of UdeM's Faculty of Medicine and a Canada Research Chair in Nutrition and Health Inequalities, to discuss the problem and his role in addressing it.
As a principal investigator, you worked with colleagues at the University of Ottawa and the Assembly of First Nations to draft the First Nations Food, Nutrition and Environment Study. Why did it take a decade to produce?
I came along in 2010 but the study had begun in 2008, spearheaded by Olivier Receveur at UdeM with other colleagues. We consulted with a lot of people: nearly 6,500 in all, from 92 First Nations across the country. And the story that emerged was incredibly complex but also astonishingly simple: everyone thinks traditional foods are better than store-bought ones, but getting proper access to them is incredibly difficult. That's one reason why nutrition is problematic on reserves—and the solution to it is by no means easy to come up with.
How do you and your co-authors of the FNFNES report recommend remedying the situation?
It's all set out in the nine-page report of findings and recommendations we just released, as well as in a new 20-page summary we prepared for eight AFN regions. In a nutshell, we say that traditional food is by and large very safe to consume and is by far healthier. However, many barriers exist between First Nations and their preferred food, including government regulations, industry and, most importantly, the increasing threat of climate change. We also point to the lack of sovereignty over food resources and health services in general.
What was your role specifically in drafting the FNFNES study and what did you learn in the process?
We're three principal investigators on the study: Laurie Chan from UofO, Tonio Sadik from the AFN and myself. I was responsible for the nutrition, food environment and food security aspects, while Laurie oversaw the environmental aspects (analysis of food samples for contaminants, as well as water samples for pharmaceuticals, and metals and hair for mercury), and Tonio and the AFN team ensured respectful and continuous engagement with First Nations.
We believe our study was pioneering in using First Nations Principles of OCAP (ownership, control, access, and possession) and insisting on a strong participatory approach. We learned that, for a successful research project, it is essential to engage the community fully and to identify community champions who are full partners of the research team. It is no longer a relationship of us (researchers) and them (the community) but us as university and community researchers working together.
We will be looking at the relationships between the food environment, diet and health outcomes of children and youth. Because FNFNES showed us that food insecurity was higher in households with children, we will investigate further what influences food security has at the household level and how we can ensure that children and their parents enjoy this basic human righ—that is, sufficient good-quality food. We understand that this work is a great responsibility as it is highly sensitive and important for policy. For example, our team has been invited to testify in front of parliamentary committees on food security issues as a result of our findings with FNFNES and I believe First Nations partners also count on this work in their endeavor to improve food and health conditions on and off reserve.Largest-ever study published on First Nations food security and environment
Poor diets imperilling people and the planet: report
Credit: Pixabay/CC0 Public Domain
Nearly half the world's population suffer from poor nutrition linked to too much or not enough food, a global assessment said Tuesday with wide-ranging impacts on health and the planet.
The Global Nutrition Report (GNR), a yearly survey and analysis of the latest data on nutrition and related health issues, found that 48 percent of people currently eat either too little or too much—resulting in them being overweight, obese or underweight.
At current rates, the report finds, the world will fail to meet eight out of nine nutrition targets set by the World Health Organization for 2025.
These include reducing child wasting (when children are too thin for their height) and child stunting (when they are too short for their age), and also adult obesity.
The report estimates nearly 150 million children under five years old are stunted, more than 45 million are wasted and nearly 40 million are overweight.
It also finds more than 40 percent of adults (2.2 billion people) are now overweight or obese.
"Avoidable deaths due to poor diets have grown by 15 percent since 2010 and poor diets are now responsible for a quarter of all adult deaths," Chair of the GNR's Independent Expert Group Renata Micha told AFP.
"Our global findings show that our diets have not improved over the last ten years and are now a major threat to people's health and to the planet."
Foods matter
This year's GNR is the first to look at global diets and how food choices are affecting people and the planet.
It finds people are failing to consume enough health-promoting foods like fruits and vegetables, particularly in lower-income countries.
Higher-income countries had the highest intake of foods with harmful health impacts like red meat, dairy and sugary drinks.
Consumption of harmful foods is on the rise, the report found, with red and processed meat already at almost five times the maximum recommendation of one serving a week.
The report notes that current global nutrition targets do not mention diet, with the exception of limiting sodium, and recommends new, more holistic targets.
"The science supports a food-based approach or diet-pattern approach in assessing the impacts on health and the environment," Micha said.
In line with other estimates, the GNR calculated global food demand generated some 35 percent of greenhouse gas emissions in 2018.
"Animal-source foods have generally higher environmental footprints per product than plant-based foods," the report said.
"Consequently, they were responsible for the majority of food-related greenhouse gas emissions and land use, with particularly large impacts from beef, lamb and dairy."
The report called for urgent funding to improve nutrition across the globe, particularly as COVID-19 has pushed an estimated additional 155 million people into extreme poverty.
The prehistoric archaeological site Jordan River Dureijat ("Jordan River Stairs") on the shores of the Paleo Lake Hula. The prehistoric archaeological site Jordan River Dureijat ("Jordan River Stairs") on the shores of the Paleo Lake Hula. Credit: Prof. Gonen Sharon, Tel-Hai College
Based on the identification of plant remains, Tel Aviv University and Tel-Hai College researchers provide the first detailed reconstruction of the climate in the Land of Israel at the end of the last ice age (20,000-10,000 years before present). The researchers claim that significant climate changes characterizing the period, manifested by sharp differences in temperature and precipitation not only seasonally but throughout the year, were a significant influence in the transition from a nomadic hunter-gatherer society to permanent settlement and an agricultural way of life. The study also provides the first information pertaining to the history of the region's flora and its response to past climate change. Against the backdrop of the Glasgow climate conference, the researchers believe that understanding the response of the region's flora to the dramatic past climate changes can help in preserving the regional variety of plant species and in planning for current and future climate challenges.
The research was conducted by Dr. Dafna Langgut of the Department of Archaeology and The Steinhardt Museum of Natural History at Tel Aviv University; Prof. Gonen Sharon, Head of the MA Program in Galilee Studies at Tel-Hai College, and Dr. Rachid Cheddadi, expert in evolution and palaeoecology of University of Montpellier, Institute of Evolutionary Sciences (ISEM) Montpellier, France. The groundbreaking study was recently published in the leading scientific journal Quaternary Science Reviews.
The study was conducted at the prehistoric archaeological site Jordan River Dureijat ("Jordan River Stairs") on the shores of the Paleo Lake Hula. The site is unique for its exceptional preservation conditions yielding finds that enabled discovery of the primary activity of its early local residents—fishing. Botanic remains preserved also enabled researchers to identify the plants that grew 10,000—20,000 years ago in the Hula Valley and its surroundings.
Dr. Dafna Langgut. Credit: Sasha Flit/Tel Aviv University
Two major processes in world history took place during this period: the transition from a nomadic to a settled lifestyle that occurs during a period of dramatic climate change. Prof. Sharon, supervisor of the Madregot Hayarden excavation, explains that "in the study of prehistory, this period is called the Epipalaeolithic period. At its outset, people were organized in small groups of hunter-gatherers who roamed the area. Then, about 15,000 years ago, we are witness to a significant change in lifestyle: the appearance of settled life in villages, and additional dramatic processes that reach their apex during the Neolithic period that followed. This is the time when the most dramatic change of human history occurred—the transition to the agricultural way of life that shaped the world as we know it today."
Dr. Dafna Langgut collecting sediment samples for fossil pollen investigation. Credit: Prof. Gonen Sharon, Tel-Hai College.
Dr. Langgut, an archaeobotanist specializing in identification of plant remains, elaborates on the second dramatic process of this period, the climatic changes that occurred in the region. "Although at the peak of the last ice age, about 20,000 years ago, the Mediterranean Levant was not covered with an ice sheet as in other parts of the world, the climatic conditions that existed nevertheless differed from those of today. Their exact characteristics were unclear until this study. The climatic model that we built is based on reconstruction of the fluctuation of the spread of plant species indicating that the main climatic change in our area is expressed by a drop in temperature (up to five degrees Celsius less than today), whereas the precipitation amounts were close to those of today (only about 50 mm less than today's annual average).
However, Dr. Langgut explains that about 5,000 years later, in the Epipalaeolithic period (about 15,000 years ago) a significant improvement in climate conditions can be seen in the model. An increased prevalence of heat-tolerant tree species, such as olive, common oak, and Pistacia, indicate an increase in temperature and precipitation. During this period, the first sites of the Natufian culture appear in our region. It could very well be that the temperate climate assisted in the development and flourishing of this culture, in which permanent settlement, stone structures, food storage facilities, and more first appear on the global stage.
The next stage of the study deals with the end of the Epipalaeolithic period, about 11,000-12,000 years ago, known globally as the Younger Dryas period. This period is characterized by a return to a cold, dry climate like that of the ice age, causing somewhat of a climate crisis around the world. The researchers claim that until this study, it was unclear whether and to what extent there was any expression of this period in the Levantine region.
Chart of Fossil pollen grains. Credit: Dr. Dafna Langgut
According to the researchers "the findings that arise from the climate model presented in the article show that the period was characterized by climatic instability, intense fluctuations, and a considerable drop in temperatures. Nevertheless, while reconstructing the precipitation, a surprising phenomenon was discovered: the average quantities of rainfall reconstructed were only slightly less than those of today; however, the precipitation was distributed over the entire year, including summer rains."
The researchers claim that such distribution assisted in the expansion and thriving of annual and leafy plant species. The gatherers who lived in this period now had a wide, readily available variety of gatherable plants throughout the entire year. This variety enabled their familiarity just before domestication. The researchers are of the opinion that these findings contribute to a new understanding of the environmental changes that took place on the eve of the transition to agriculture and domestication of animals.
Dr. Langgut concludes that "this study contributes not only to understanding the environmental background for momentous processes in human history such as the first permanent settlement and the transition to agriculture, but also provides information on the history of the region's flora and its response to past climatic changes. There is no doubt that this knowledge can assist in preserving species variety and in meeting current and future climate challenges."Sediments from lake in Japan reveal stable climate led to origin of agriculture
More information:Dafna Langgut et al, Climate and environmental reconstruction of the Epipaleolithic Mediterranean Levant (22.0–11.9 ka cal. BP),Quaternary Science Reviews(2021).DOI: 10.1016/j.quascirev.2021.107170
Experiments with different lighting situations (wall, desk and ceiling).Credit: Eindhoven University of Technology
Although we usually do not realize this, lighting is an essential part of our daily lives. After all, without light, no sight. Next to enabling us to see safely and comfortably move from place A to B, lighting also has a large impact on how we perceive and appreciate spaces. Ph.D. student Adrie de Vries has investigated how lighting affects the experience and performance of knowledge workers in an open-plan office. He will defend his thesis on Wednesday 24 November at the departent of Industrial Engineering and Innovation Sciences.
To investigate this, Adrie de Vries used three separate experiments to analyze how office workers perceived and experienced different lighting effects on the wall, the desk and the ceiling respectively. He also tried to relate this to task performance of knowledge workers. Although these types of investigations are typically done in highly controlled and often unrealistic environments, he chose environments that closely mimicked realistic, multi-user offices to ensure that the findings would also be representative and applicable to real world cases.
First, the effect of lighting the wall was studied and was found to have a clear effect on how people experienced the space. Increasing the light level on the wall rendered not only a brighter but also a more attractive environment. Moreover, although he did not find any effects on task performance, people did feel more alert in the spaces with more light on the walls and they stayed more alert there as well.
In contrast, varying the amount of light on the desk (with a constant amount of light on the wall) mainly impacted how well people could read from paper, and how bright people perceived the space, but did not impact alertness, task performance, or the attractiveness of the office space.
For the ceiling illumination, he found an increase in attractiveness and brightness when more light was directed to the ceiling. Additionally, the spaces were judged more attractive when spreading the light more evenly over the ceiling.
Appreciative vs. indifferent
Another important finding was that not all participants were equally sensitive and appreciative to changes in brightness. Although people having different opinions of what they like is not new, the fact that the researcher could clearly separate them in a sensitive, appreciative group and an indifferent, mildly negative group, was a new and useful finding for future research.
Finally, De Vries investigated if he could predict the brightness perceptions of individuals with accurate measurements of the lighting. He found that measurements of specific parts of the field of view provided a reasonable prediction of how bright people would assess the space and that both the average and the contrast in the field of view mattered.
Integrative design and diversity
The researcher concludes that illuminating the walls, ceilings and desks can all result in brighter spaces, however, in this case, only lighting the walls and ceiling resulted in more attractive spaces. Additionally, lighting for example the walls can also support occupants in maintaining their alertness instead of becoming more sleepy. This shows that lighting does more than simply provide sufficient light to read, but also impacts how we experience spaces, and how we "feel."
Importantly though, although it was possible to draw several overall conclusions, we are dealing with a highly diverse workforce, which can and will have different requirements for their "great place to work."
