Daughters breastfed longer, and women accumulated greater wealth in ancient California matriarchal society

Women managed important food resources, which may have incentivized parents to invest more in female offspring and to female-biased wealth disparities.

Peer-Reviewed Publication

UNIVERSITY OF UTAH

 

IMAGE: WOMAN MEASURING A STRAND OF SHELL BEADS IN A PHOTO TAKEN IN 1918. view more 

CREDIT: JOHN P. HARRINGTON

In a new study, researchers and members of the Muwekma Ohlone Tribe of the San Francisco Bay Area are the first to publish evidence of wealth-driven patterns in maternal investment among ancient populations.

Ancestors of the Muwekma Ohlone living 2,000 years ago at Kalawwasa Rummeytak in present-day Silicon Valley in California’s San Francisco Bay Area, placed high value on women’s economic contributions to their communities, according to the study. Women stayed in the villages in which they were born, and their male partners moved from their birth communities to join their wives’ families. Women’s intimate knowledge of the local ecology and female ownership of important food resources appears to have incentivized parents to invest more in their female offspring by breastfeeding them longer. It may have also led to female-biased wealth disparities, as older women at the site were buried with much greater wealth than men.

“Ohlone ancestors living at Kalawwasa Rummeytak relied heavily on women’s contributions to the economy, so they structured their marriage and family systems around women to keep them in their natal communities,” said Dr. Alexandra Greenwald, anthropologist at the University of Utah and curator of ethnography at the Natural History Museum of Utah. “We can also see that placing a high value on women’s contributions led to greater investment in their well-being as children and created greater opportunities for them to accumulate wealth and prestige over their lifetimes.”

Over the past four decades, the Muwekma Ohlone tribal leadership has had oversight over many of the tribe’s ancestral heritage sites within their ethnohistoric home of the San Francisco Bay Area. The Muwekma Ohlone Language Committee has renamed many of the tribe’s cemetery, village sites and sacred places to counter the colonial legacies and politics of erasure perpetrated by the Spanish Empire, and the ensuing American conquest of California. In 2001, the tribe’s language committee renamed a cemetery site located in the City of Santa Clara where the tribe and San Jose State University staff and students recovered 24 ancestral remains. The site’s name, Kalawwasa Rummeytak, means Place of the Calabazas Creek Site.

“Given the fact that there was no funding for analysis or reburial, our team produced a preliminary report on the excavation and skeletal analysis,” said Muwekma Ohlone Tribal Vice-Chairwoman Monica V. Arellano and co-author of the study. “The Muwekma Ohlone Tribal Council voted to support the proposed research that has become the current published study.”

The study published on July 12, 2023, in The American Journal of Biological Anthropology.

The authors, led by Greenwald, used Strontium isotopes to assess Ohlone ancestors’ movement across the landscape throughout their lives. Strontium is incorporated into a person’s tissues from the water they drink, which bears the local geological signature. By sampling from tissues like bone and teeth that grow at specific points in an individual’s life, archaeologists can track the person’s movement. The analysis revealed that the group practiced a matrilocal kinship system where men marry and move into their wife’s village.

In other societies that follow a matrilocal kinship system, mothers invest more resources into their daughters who remain in their community and contribute to the local economy. To test whether Kalawwasa Rummeytak mothers prioritized their female offspring, the authors were interested in examining how they breastfed their children. Because lactation is costly to mothers from a caloric and time perspective, scientists considered weaning age an important measure of parental investment among mammals.

To reconstruct the infant and childhood diets of Kalawwasa Rummeytak residents, the authors measured carbon and nitrogen isotope ratios contained in permanent first molars. First molars begin forming at birth and grow in layers, akin to tree rings. These layers incorporate isotopic signatures from the food that the infant is consuming, and can be tied directly to the age of the individual when the layer was formed. 

“Infants who are breastfeeding exhibit greater nitrogen enrichment because they’re consuming breastmilk, which is synthesized from their mother’s bodily tissues,” Greenwald explained. “Using this method, we could track down to the month how long each individual at Kalawwasa Rummeytak was breastfed.”

On average, the women interred at the site were breastfed five months longer than the males, suggesting that parents prioritized their female offspring’s nutrition. On average, girls were weaned at 36 months, and boys at 31 months. When comparing the average weaning age of individuals who were born at the site, and those who moved there in early adulthood, the authors found a significant difference. Locals were breastfed an average of 42 months versus 32.5 months for non-locals.

Not only were women at Kalawwasa Rummeytak breastfed longer as girls, but they also held a disproportionate amount of wealth. Prior to contact with the Spanish and Euromericans, Indigenous Californians developed a form of money using shell beads. Individuals buried with large quantities of beads are assumed by archaeologists to have achieved greater wealth and status in their lifetime. At Kalawwasa Rummeytak, only older women are interred with shell beads. 

“This case stands out as the most definitive example in ancient California of burial wealth concentrated among women,” said coauthor Gregory Burns of the University of Utah, an expert in the shell bead economy.

The findings highlight the flexibility human societies to shift their kinship strategies in response to local ecological conditions.

“Our tribal leadership is honored to have worked and co-authored with these scholars and hopefully such analyses will leave our tribal membership, Native Americans and the scientific community a meaningful legacy that contributes to the understanding of our ancestral lifeways and adaptive strategies left by our ancestors,” said Vice Chairwoman Arellano.

Other authors of the study include Jelmer Eerkens of the University of California, Davis, Eric Bartelink of California State University, Chico, Muwekma Ohlone Archaeologist Alan Leventhal of San Jose State University, and Monica Arellano, vice chairwoman of the Muwekma Ohlone Tribe of the San Francisco Bay Area and vice president of Muwekma Ohlone Tribe, Inc.

The study was funded by the National Science Foundation grant number BCS-1318532.

The location of the Kalawwasa Rummeytak site near Santa Clara, California.

CREDIT

Adapted from Greenwald, et. al., (2023) Am J Bio Anthro

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JOURNAL

American Journal of Biological Anthropology

DOI

10.1002/ajpa.24806 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Human tissue samples

ARTICLE TITLE

Sex-biased parental investment and female wealth accumulation in ancient California

ARTICLE PUBLICATION DATE

12-Jul-2023

THIRD WORLD U$A

Food insecurity rate hits 17% for the second time in 18 months

Reports and Proceedings

PURDUE UNIVERSITY

 

IMAGE: PREDICTED CHANGES TO FOOD SPENDING AS A RESULT OF A 25% INCOME LOSS FROM RECESSION, JUNE 2023. view more 

CREDIT: CREDIT: PURDUE UNIVERSITY CENTER FOR FOOD DEMAND ANALYSIS AND SUSTAINABILITY

Food insecurity rate hits 17% for the second time in 18 months

WEST LAFAYETTE, Ind. – Reported food insecurity has reached 17%, matching the rate last reached in March 2022, according to the June Consumer Food Insights Report. The new report also includes consumer changes in food spending as a result of a hypothetical recession and sentiments on artificial intelligence.

The survey-based report out of Purdue University’s Center for Food Demand Analysis and Sustainabilityassesses food spending, consumer satisfaction and values, support of agricultural and food policies, and trust in information sources. Purdue experts conduct and evaluate the survey, which includes 1,200 consumers across the U.S.

“Overall, there continues to be a similar narrative of extended upward pressure on food prices as we try to discern whether this stress has led to a tipping point where consumers are struggling to buy the foods that they want,” said Jayson Lusk, the head and Distinguished Professor of Agricultural Economics at Purdue, who leads the center. 

“The 17% food insecurity rate is up from 14% just two months ago, which is not necessarily far outside of the normal variation we have measured. However, this increase could be concerning given the sum of external pressures being exerted on more vulnerable consumers,” Lusk said.

He noted that pandemic-related boosts to the Supplemental Nutrition Assistance Program (SNAP) ended in March. The insecurity rise could be a lag from households adjusting to this policy change.

In the event of a recession, consumers report that they would cut back most on steak, pork and dining out. These results align with what Lusk would expect to occur if incomes fell.

“Discretionary spending on eating out will go first if consumers have to face a recession. Then people will cut back on more expensive items that they can easily substitute in their diets. Steak and bacon, for example,” Lusk said. “It is interesting to see that the items with a large share of ‘does not apply’ are also largely items that will be cut back the most as many people are already choosing to forgo them.”

Additional key results include: 

• Reported food spending has risen by 2.1% from last June, which is much less than the 6.7% government estimate of food inflation.
• Households making less than $50,000 annually are buying groceries online at a higher rate than other households. 
• The report noted that the pandemic opened the online option to SNAP recipients, which evidently remains a key tool for a range of shoppers.
• Households making more than $100,000 annually are slightly greater risk-takers, which is reflected by a higher willingness to eat unwashed fruits and undercooked meat.
• Consumers largely have positive or neutral feelings about applying artificial intelligence (AI) in the food and agriculture sectors.

“The artificial intelligence questions are much more speculative since there are not yet widely known examples of AI being used across the food system,” said Sam Polzin, a food and agriculture survey scientist for the center and co-author of the report. “People really do not have enough information about AI to have thoughtful positions, as seen in the large share of indifference.”

Surprisingly to Polzin, 50% of consumers said they would be OK with AI helping them make food choices, which is generally considered a personal decision. “This proportion might be indicative of how eager people are to make the ‘best’ choices,” Polzin said.

According to the U.S. Bureau of Labor Statistics, annual inflation for food-at-home fell below inflation for food-away-from-home (FAFH) this spring, he noted. This poses the question: Will consumers continue to spend at faster rates on dining out?

“The highest earners are driving a larger share of the increase in FAFH spending and have no clear reason to slow down. We will keep track of whether two different patterns emerge in which higher-income households continue to thrive while lower-income households might be forced to pull back,” Polzin said.

The report’s results about food behaviors align with other research showing that high-wage consumers take higher risks than those earning less. “The fact that higher earners report eating unwashed fruits, undercooked meat and raw dough slightly more often could reflect this risk-taking,” Polzin said.

Other reported food behaviors are fairly expected. High-income households, for example, will choose premium local and organic products more often than lower-income households. They also often have more resources to track and understand food labeling or follow recycling and composting practices.

Lusk further discusses the report in his blog.

The Center for Food Demand Analysis and Sustainability is part of Purdue’s Next Moves in agriculture and food systems and uses innovative data analysis shared through user-friendly platforms to improve the food system. In addition to the Consumer Food Insights Report, the center offers a portfolio of online dashboards.

Writer: Steve Koppes

Consumer support for the application of AI in food and agriculture, June 2023.

CREDIT

Purdue University Center for Food Demand Analysis and Sustainability

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METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

June Consumer Food Insights Report

ARTICLE PUBLICATION DATE

12-Jul-2023

Virginia Tech awarded $3.4 million grant to study the environmental effects of utility-scale solar installations

The study, funded by the Department of Environmental Quality, is “collecting the data we need to do solar right.”

Grant and Award Announcement

VIRGINIA TECH

As utility-scale solar farms become more widespread as a source of renewable energy, Virginia Tech scientists are researching environmental consequences with respect to stormwater and the sediment and nutrients transported in runoff.

With a $3.4 million grant from the Virginia Department of Environmental Quality, researchers from the College of Agriculture and Life Sciences will lead a comprehensive six-year study to determine how utility-scale solar farms impact stormwater runoff and local soil and water quality throughout the state.

“Solar is probably going to be the No. 1 land use change that will occur over the next decade in many parts of Virginia, particularly in existing agricultural and forested areas,” said Ryan Stewart, associate professor in the School of Plant and Environmental Sciences and lead investigator of the project. “Even if it’s not your neighbor’s property, these sites will be somewhere nearby. We’re collecting the data we need to do solar right.”

Virginia ranks ninth in the nation for solar production, according to the Solar Industries Association, with 52 active utility-scale solar facilities generating upwards of 4,296 megawatts — enough to power 476,000 homes. Since Virginia passed the Clean Economy Act in 2020, mandating a transition to 100 percent renewable energy by 2050, the Virginia Department of Environmental Quality (DEQ) has received 50 active notices of intent from companies planning to build utility-scale solar installations. To meet Virginia’s 2050 renewable energy goal of 16,100 megawatts, as many as 161,000 acres — or about 10 acres per megawatt — would be needed.

“The research question we are addressing here is: Is there a change in the soil and hydrology?” Stewart said. “The DEQ wants to know if and how these solar installations should be regulated and how they should be siting infrastructure. There’s just not a lot of data out there and what is available is either not really applicable to this type of project or it’s outdated.”

In addition to helping inform DEQ regulatory policy, the study will offer guidance to localities considering solar farm proposals. Industry partners, including Dominion Energy, AES Corporation, Energix, and Urban Grid, have stepped forward to participate in the study by offering their solar facilities as research sites as well as providing commitments of cash and in-kind support for this research totaling over $500,000 to date.

“The industry, in general, is supportive of this research because our approach is we are going to go out to these sites and actually measure to see which models work and which don’t,” said co-investigator W. Lee Daniels, the Thomas B. Hutcheson Jr. Emeritus Professor of Environmental Science. “Even though it’s a six-year project, that feedback loop to our cooperators will start occurring as soon as we have data and we can validate it.”

The team will select six sites throughout Virginia to study — three fully developed, revegetated solar sites and three that will be monitored from pre-development through installation, revegetation, and their full operating phase. Each solar farm will be outfitted with multiple monitoring locations, instrumented to collect data on rainfall, surface water level, air temperature, and specific conductance. Flow-weighted composite samples taken from storm events will be analyzed for pH, sediment, nitrogen, phosphorous, and other potential contaminants.

The study will represent one of the largest collections of actual runoff data in Virginia since several localities contributed to the Environmental Protection Agency’s Nationwide Urban Runoff Program completed in the 1980s, which still underpins many of the current runoff and watershed modeling applications in the Chesapeake Bay region. These models are extremely important in measuring progress toward achieving environmental goals such as the Total Maximum Daily Load for the Chesapeake Bay.

“In terms of modeling applications and validating and improving models, this data will be really useful and valuable to a lot of people,” Daniels said. “This work is going to generate data that would also be applicable to construction sites, mixed-use sites, and pasture sites, for example. We’ll have actual numbers to update all these 30- and 40-year-old assumed values that are underlying our models right now.”

The research team integrates expertise from Virginia Tech and Virginia State University. Stewart, the lead principal investigator, is an expert in soil hydrology and stormwater infiltration. Daniels is an authority in the rehabilitation of disturbed lands who will assist with soil disturbance studies and work directly with the industry and DEQ. David Sample, professor of biological systems engineering and Extension specialist based at the Hampton Roads Agricultural Research and Extension Center, will lead efforts to model stormwater flows and local water quality impacts.

Sample recently conducted two similar stormwater monitoring studies in the cities of Virginia Beach and Fredericksburg.

“Each of these efforts will help expand our knowledge of runoff water quality and will help guide the design of mitigation measures and stormwater treatment,” Sample said.

Advanced Extension Specialist John Ignosh with Virginia Cooperative Extension will facilitate stakeholder communication and provide field equipment support.

Co-investigators Vitalis Temu and Maru Kering, both associate professors at Virginia State University’s Agricultural Research Station, will monitor how site vegetation reacts with solar panels and storm events.

“As society tries to confront climate change and look for sources of renewable energy, solar will be part of our energy portfolio for a while,” Stewart said. “The chance to collect this kind of runoff data in the field and at this scale is rare, so we are very excited for that.”

This research underpins Virginia Tech’s commitment to sustainability, as the university was again ranked among the top 100 universities globally in the Times Higher Education 2023 Impact Rankings.

The Times Higher Education Impact Rankings are the only global performance tables that assess universities against the United Nation’s Sustainable Development Goals. The rankings use calibrated indicators to compare universities across four areas: research, stewardship, outreach, and teaching.

Virginia Tech received an overall score of 89 and an impact ranking of No. 92 out of nearly 1,600 universities. More information about Virginia Tech’s rankings can be found online.

Fungi blaze a trail to fireproof cladding

RMIT scientists have shown it’s possible to grow fungi in thin sheets that could be used for fire-retardant cladding or even a new kind of fungal fashion.

Peer-Reviewed Publication

RMIT UNIVERSITY

 

IMAGE: LEAD AUTHOR NATTANAN CHULIKAVIT SHOWS OFF THE COMPRESSED MYCELIUM SHEETS SHE CREATED FOR THE PROJECT. view more 

CREDIT: RMIT UNIVERSITY

Mycelium, an incredible network of fungal strands that can thrive on organic waste and in darkness, could be a basis for sustainable fireproofing. RMIT researchers are chemically manipulating its composition to harness its fire-retardant properties.

Associate Professor Tien Huynh, an expert in biotechnology and mycology, said they’ve shown that mycelium can be grown from renewable organic waste.

“Fungi are usually found in a composite form mixed with residual feed material, but we found a way to grow pure mycelium sheets that can be layered and engineered into different uses – from flat panels for the building industry to a leather-like material for the fashion industry,” said Huynh, from the School of Science.

The novel method of creating mycelium sheets that are paper-thin, like wallpaper, works without pulverising the mycelium’s filament network. Instead, they used different growth conditions and chemicals to make the thin, uniform and – importantly – first resistant, material.

Fungi fireproofing our buildings

The researchers are focused on creating bio-derived, fire-retardant cladding for buildings to prevent tragedies like the Grenfell Tower fire, in which the deadly blaze was accelerated by a highly combustible cladding component.

Associate Professor Everson Kandare, an expert in the flammability and thermal properties of biomaterials and co-author of the paper, said the mycelium has strong potential as a fireproofing material.

“The great thing about mycelium is that it forms a thermal protective char layer when exposed to fire or radiant heat. The longer and the higher temperature at which mycelium char survives, the better its use as a fireproof material,” said Kandare.

Beyond being effective, mycelium-based cladding can be produced from renewable organic waste and is not harmful to the environment when burned, he explained.

Where composite cladding panels are used, they usually contain plastics – which produce toxic fumes and heavy smoke when they burn.

“Bromide, iodide, phosphorus and nitrogen-containing fire retardants are effective, but have adverse health and environmental effects. They pose health and environmental concerns, as carcinogens and neurotoxins that can escape and persist in the environment cause harm to plant and animal life,” said Kandare.

“Bioderived mycelium produces naturally occurring water and carbon dioxide.”

Bringing the research to life

This research could eventually lead to improved and eco-friendly cladding for buildings.

“Plastics are quick and easy to produce, whereas fungi is slow to grow and relatively harder to produce at scale,” said Huynh.

“However, we’ve been approached by the mushroom industry about using their fungal-incorporated waste products. Collaborating with the mushroom industry would remove the need for new farms while producing products that meet fire safety needs in a sustainable way.”

The researchers are now looking to create fungal mats reinforced by engineering fibres to delay ignition, reduce the flaming intensity and improve fire safety ranking.

The paper, “Fireproofing flammable composites using mycelium: Investigating the effect of deacetylation on the thermal stability and fire reaction properties of mycelium” (https://doi.org/10.1016/j.polymdegradstab.2023.110419, lead author Nattanan Chulikavit), is published in the journal Polymer Degradation and Stability.

It builds on preliminary research published by the experts in high-ranked international journals, Polymer Degradation and Stability and Nature’s Scientific Reports.

This project is a major collaboration involving RMIT University, the University of New South Wales, the Hong Kong Polytechnic University and the Australian Research Council Training Centre in Fire Retardant Materials and Safety Technologies.

The research team Nattanan (Becky) Chulikavit (left), Associate Professor Tien Huynh (middle) and Associate Professor Everson Kandare (right) in their lab at RMIT’s Bundoora campus.

CREDIT

RMIT University

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JOURNAL

Polymer Degradation and Stability

DOI

10.1016/j.polymdegradstab.2023.110419 

METHOD OF RESEARCH

Experimental study

SUBJECT OF RESEARCH

Cells

ARTICLE TITLE

Fireproofing flammable composites using mycelium: Investigating the effect of deacetylation on the thermal stability and fire reaction properties of mycelium

Poignant photo project reveals all we lost in lockdown

Peer-Reviewed Publication

UNIVERSITY OF EAST ANGLIA

 

VIDEO: LAPTOPS AND SCHOOLWORK ON KITCHEN TABLES, A DESERTED PLAYGROUND, FACE MASKS ON A WASHING LINE, AN EMPTY CHURCH, A WALK IN THE WOODS. AS THE UK COVID INQUIRY CONTINUES FOR A FIFTH WEEK, RESEARCHERS AT THE UNIVERSITY OF EAST ANGLIA HAVE CREATED A UNIQUE SNAPSHOT OF LOCKDOWN LIFE. view more 

CREDIT: UNIVERSITY OF EAST ANGLIA

Laptops and schoolwork on kitchen tables, a deserted playground, face masks on a washing line, an empty church, a walk in the woods.

As the UK Covid inquiry continues for a fifth week, researchers at the University of East Anglia have created a unique snapshot of lockdown life.

When the pandemic first hit, the team embarked on a project to track the physical and mental health of the nation. More than a thousand participants signed up and up and they were followed every day for three months in the first study of its kind.

As well as keeping daily lifestyle diaries about their physical activity, diet and mood, the participants were asked to submit photographs that captured their life in lockdown.

The research team studied these images, and a new paper published today reveals just how much people lost during Covid.

The images illustrate an “unequal pandemic”, the researchers say.

But they also reveal how and why some people fared better than others during lockdowns and beyond.

Lead researcher Prof Caitlin Notley, from UEA’s Norwich Medical School, said: “People around the world had to change their lifestyles very quickly in response to the Covid pandemic.

“We set out to track people’s health and lifestyle behaviours to help answer important questions about the overall impact of the pandemic on health.

“To help us really understand what life was like, we asked our participants to submit photographs that captured their experiences of lockdown.”

Almost 400 photos were submitted, along with short descriptions to accompany them, giving testimony to people’s lived experiences. 

Dr Sarah Hanson, from UEA’s School of Health Sciences, said: “A recurrent theme through the images is one of loss – of both freedoms, and lives.

“But the photographs also illustrate people’s starkly different experiences of life in lockdown - it was a very unequal pandemic.

“For those with limited control over their lives and in poorer circumstances the pandemic exacerbated already difficult lives and communities that are struggling to recover.

“The pandemic has been devastating to many people and social groups and our findings show the many unintended social consequences of lockdown.

“It is right that lives return to normality but there are still people shielding, communities have suffered and people are still deeply affected by what happened during those times and the sense of loss by many is profound.

“Those who had more resources and more control over their lives were more easily able to find comfort, find a way to be socially connected and to develop a sense of resilience. It tended to be those who were better off financially, had gardens, had a computer and internet at home, and who were able to work from home, that were able to cope with it better.

“We should also be mindful that even for those who appeared to cope well, the trauma can be covert and issues can emerge as significant psychological issues later on,” she added.

‘Lest we Forget. Illuminating lived experience of the Covid-19 pandemic and lockdown’ is published in the journal Social Science & Medicine.

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JOURNAL

Social Science & Medicine

METHOD OF RESEARCH

Survey

SUBJECT OF RESEARCH

People

ARTICLE TITLE

Lest we Forget. Illuminating lived experience of the Covid-19 pandemic and lockdown

ARTICLE PUBLICATION DATE

13-Jul-2023

Unemployment and underemployment significant drivers of suicide: Analysis

Peer-Reviewed Publication

UNIVERSITY OF SYDNEY

A study examining unemployment and underemployment figures and suicide rates in Australia has found both were significant drivers of suicide mortality between 2004-2016.

The researchers say the findings indicate that economic policies such as a Job Guarantee, which prioritise full employment, should be a core part of any comprehensive national suicide prevention strategy.

Predictive modelling also revealed an estimated 9.5 percent of suicides reported during that time resulted directly from unemployment and underemployment.

The analysis used national data, which included numbers of suicides per month provided by the Australian Institute of Health and Welfare, and monthly unemployment and underemployment statistics from the Australian Bureau of Statistics.

The 13-year period includes the Global Financial Crisis (mid 2007 to early 2009) and the beginning of the Robodebt scheme (July 2016).

Between 2004 – 2016, approximately 1 in 10 of the 32,331 suicides in total were estimated to result from labour underutilisation (3071 suicides or 9.5 percent).

1575 suicides were attributed to unemployment (4.9 percent of total suicide mortality). 1496 suicides are attributed to underemployment (4.6 percent)

The study, published in Science Advances, was led by researchers from the Brain and Mind Centre at the University of Sydney.

The results are consistent with epidemiological studies (independent of this study) that found changes from employment to unemployment tend to produce a significant increase in psychological distress. 

“Our analyses provide evidence that rates of unemployment and underemployment were significant drivers of suicide mortality in Australia during that time,” said lead researcher Dr Adam Skinner from the Brain and Mind Centre.

“Ensuring adequate employment for every person seeking work is an effective way to reduce the immense personal and social cost of intentional self-harm and suicide.”

The study used a relatively new analytical method called convergent cross mapping to confirm causal effects of underemployment and unemployment over time on suicidal behaviour.

The strength of convergent cross mapping is that it allows researchers to detect cause and effect in complex systems, where significant correlation between variables does not necessarily indicate causality.

Predictive modelling was used to estimate the number of suicides caused by labour underutilisation per month. 

“The study confirms that a high priority in suicide prevention should be full employment, particularly as we now face economic uncertainty in Australia,” said Brain and Mind Centre co-director, Professor Ian Hickie AM.

“Rising unemployment costs lives - particularly amongst those most vulnerable groups.”

-ENDS-

• Lifeline on 13 11 14
• Kids Helpline on 1800 551 800
• MensLine Australia on 1300 789 978
• Suicide Call Back Service on 1300 659 467
• Beyond Blue on 1300 22 46 36
• Headspace on 1800 650 890
• QLife on 1800 184 527
• ReachOut at au.reachout.com

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JOURNAL

Science Advances

DOI

10.1126/sciadv.adg3758 

ARTICLE TITLE

Unemployment and underemployment are causes of suicide

ARTICLE PUBLICATION DATE

12-Jul-2023

COI STATEMENT

Declaration: Refer to the published paper for full details. I.B.H. has previously led community-based and pharmaceutical industry-supported projects focused on the identification and better management of anxiety and depression. He was a member of the Medical Advisory Panel for Medibank Private until October 2017, a board member of Psychosis Australia Trust, and a member of Veterans Mental Health Clinical Reference Group. He is the Chief Scientific Advisor to, and a 3.2% equity shareholder in, InnoWell Pty Ltd. Adam Skinner, Nathaniel Osgood and Christine Song declare that they have no competing interests.