These bones were made for walking

 Perhaps the most profound advance in primate evolution occurred about 6 million years ago when our ancestors started walking on two legs. The gradual shift to bipedal locomotion is thought to have made primates more adaptable to diverse environments and freed their hands to make use of tools, which in turn accelerated cognitive development. With those changes, the stage was set for modern humans.

The genetic changes that made possible the transition from knuckle-based scampering in great apes to upright walking in humans have now been uncovered in a new study by researchers at Columbia University and the University of Texas.

Using a combination of deep learning (a form of artificial intelligence) and genome-wide association studies, the researchers have created the first map of the genomic regions responsible for skeletal changes in primates that led to upright walking. The map reveals that genes that underlie the anatomical transitions observed in the fossil record were strongly acted on by natural selection and gave early humans an evolutionary advantage.

"On a more practical level, we've also identified genetic variants and skeletal features that are associated with hip, knee, and back arthritis, the leading causes of adult disability in the United States," says Tarjinder Singh, PhD, assistant professor of computational and statistical genomics (in psychiatry) at the Columbia University Vagelos College of Physicians and Surgeons and a co-leader of the study.

For example, slight deviations from the average hip width-to-height ratio were associated with an increased risk of hip osteoarthritis, while slight deviations in the tibia-femur angle were associated with an increased risk of knee osteoarthritis. These insights could help researchers devise new ways to prevent and treat these debilitating conditions.

The findings were published July 21 in Science. The study was co-led by Vagheesh M. Narasimhan, PhD, assistant professor of integrative biology and of statistics and data sciences at the University of Texas at Austin.

New techniques deployed

The researchers applied deep learning to analyze more than 30,000 full-body X-rays from the UK Biobank. Deep learning, a technology modeled after the brain's neural networks, trains computers to do what comes naturally to humans, such as driving a car or translating languages. In this case, the technique was used to standardize the X-rays, remove any images with quality issues, and then precisely measure dozens of skeletal features, tasks that would have taken the researchers months, if not years, to complete.

Next, the researchers scanned the human genome to identify chromosomal regions associated with variations in 23 key skeletal measures, such as shoulder width, torso length, and tibia-to-femur angle. (These scans, called genome-wide association studies, involve surveying the genomes of large groups of people, looking for genomic variants that occur more frequently in those with a specific disease or trait compared to those without the disease or trait.) This process revealed 145 regions associated with genes that regulate skeletal development. Only a handful of these loci were known from previous studies.

Many of the 145 regions overlapped with "accelerated" regions of the human genome, which have rapidly evolved over eons compared with the same regions in great apes. In contrast, few genes associated with the heart, immune system, metabolism, and other traits were found in accelerated regions.

"What we're seeing is the first genomic evidence that there was selective pressure on genetic variants that affect skeletal proportions, enabling a transition from knuckle-based walking to bipedalism," says Narasimhan.

The study also shows the power of combining large-scale biobank data, machine learning, and genomics to help us understand human health and disease. Singh, who joined Columbia in 2022, is now applying these techniques to understand the causes of mental illness.

Learning from superheroes and AI: Researchers study how a chatbot can teach kids supportive self-talk

 At first, some parents were wary: An audio chatbot was supposed to teach their kids to speak positively to themselves through lessons about a superhero named Zip. In a world of Siri and Alexa, many people are skeptical that the makers of such technologies are putting children's welfare first.

Researchers at the University of Washington created a new web app aimed to help children develop skills like self-awareness and emotional management. In Self-Talk with Superhero Zip, a chatbot guided pairs of siblings through lessons. The UW team found that, after speaking with the app for a week, most children could explain the concept of supportive self-talk (the things people say to themselves either audibly or mentally) and apply it in their daily lives. And kids who'd engaged in negative self-talk before the study were able to turn that habit positive.

The UW team published its findings in June at the 2023 Interaction Design and Children conference. The app is still a prototype and is not yet publicly available.

The UW team saw a few reasons to develop an educational chatbot. Positive self-talk has shown a range of benefits for kids, from improved sport performance to increased self-esteem and lower risk of depression. And previous studies have shown children can learn various tasks and abilities from chatbots. Yet little research explores how chatbots can help kids effectively acquire socioemotional skills.

"There is room to design child-centric experiences with a chatbot that provide fun and educational practice opportunities without invasive data harvesting that compromises children's privacy," said senior author Alexis Hiniker, an associate professor in the UW Information School. "Over the last few decades, television programs like 'Sesame Street,' 'Mister Rogers,' and 'Daniel Tiger's Neighborhood' have shown that it is possible for TV to help kids cultivate socioemotional skills. We asked: Can we make a space where kids can practice these skills in an interactive app? We wanted to create something useful and fun -- a 'Sesame Street' experience for a smart speaker."

The UW researchers began with two prototype ideas with the goal to teach socioemotional skills broadly. After testing, they narrowed the scope, focusing on a superhero named Zip and the aim of teaching supportive self-talk. They decided to test the app on siblings, since research shows that children are more engaged when they use technology with another person.

Ten pairs of Seattle-area siblings participated in the study. For a week, they opened the app and met an interactive narrator who told them stories about Zip and asked them to reflect on Zip's encounters with other characters, including a supervillain. During and after the study, kids described applying positive self-talk; several mentioned using it when they were upset or angry.

By the end of the study, all five kids who said they used negative self-talk before had replaced it with positive self-talk. Having the children work with their siblings supported learning in some cases, but some parents found the kids struggling to take turns while using the app.

The length of these effects isn't clear, researchers note. The study just spanned one week and the tendency for survey participants to respond in ways that make them look good could lead kids to speak positively about the app's effects. Future research may include longer studies in more natural settings.

"Our goal is to make the app accessible to a wider audience in the future," said lead author Chris (Yue) Fu, a UW doctoral student in the iSchool. "We're exploring the integration of large language models -- the systems that power tech like ChatGPT -- into our prototype and we plan to work with content creators to adapt existing socioemotional learning materials into our system. The hope is that these will facilitate more prolonged and effective interventions."

Other authors are Mingrui Zhang, a research scientist at Meta Reality Labs who graduated from the UW iSchool; Lynn K Nguyen, a UW research assistant in the iSchool; Yifan Lin, a UW masters student and UW doctoral student Rebecca Michelson, both in the human centered design and engineering department; and Tala June Tayebi, a masters student at the University of Southern California who did undergraduate work at the UW iSchool. This research was funded by the Jacobs Foundation and the Canadian Institute for Advanced Researchers.

AI tests into top 1% for original creative thinking

 New research from the University of Montana and its partners suggests artificial intelligence can match the top 1% of human thinkers on a standard test for creativity.

The study was directed by Dr. Erik Guzik, an assistant clinical professor in UM's College of Business. He and his partners used the Torrance Tests of Creative Thinking, a well-known tool used for decades to assess human creativity.

The researchers submitted eight responses generated by ChatGPT, the application powered by the GPT-4 artificial intelligence engine. They also submitted answers from a control group of 24 UM students taking Guzik's entrepreneurship and personal finance classes. These scores were compared with 2,700 college students nationally who took the TTCT in 2016. All submissions were scored by Scholastic Testing Service, which didn't know AI was involved.

The results placed ChatGPT in elite company for creativity. The AI application was in the top percentile for fluency -- the ability to generate a large volume of ideas -- and for originality -- the ability to come up with new ideas. The AI slipped a bit -- to the 97th percentile -- for flexibility, the ability to generate different types and categories of ideas.

"For ChatGPT and GPT-4, we showed for the first time that it performs in the top 1% for originality," Guzik said. "That was new."

He was gratified to note that some of his UM students also performed in the top 1%. However, ChatGTP outperformed the vast majority of college students nationally.

Guzik tested the AI and his students during spring semester. He was assisted in the work by Christian Gilde of UM Western and Christian Byrge of Vilnius University. The researchers presented their work in May at the Southern Oregon University Creativity Conference.

"We were very careful at the conference to not interpret the data very much," Guzik said. "We just presented the results. But we shared strong evidence that AI seems to be developing creative ability on par with or even exceeding human ability."

Guzik said he asked ChatGPT what it would indicate if it performed well on the TTCT. The AI gave a strong answer, which they shared at the conference:

"ChatGPT told us we may not fully understand human creativity, which I believe is correct," he said. "It also suggested we may need more sophisticated assessment tools that can differentiate between human and AI-generated ideas."

He said the TTCT is protected proprietary material, so ChatGPT couldn't "cheat" by accessing information about the test on the internet or in a public database.

Guzik has long been interested in creativity. As a seventh grader growing up in the small town of Palmer, Massachusetts, he was in a program for talented-and-gifted students. That experience introduced him to the Future Problem Solving process developed by Ellis Paul Torrance, the pioneering psychologist who also created the TTCT. Guzik said he fell in love with brainstorming at that time and how it taps into human imagination, and he remains active with the Future Problem Solving organization -- even meeting his wife at one of its conferences.

Guzik and his team decided to test the creativity of ChatGPT after playing around with it during the past year.

"We had all been exploring with ChatGPT, and we noticed it had been doing some interesting things that we didn't expect," he said. "Some of the responses were novel and surprising. That's when we decided to put it to the test to see how creative it really is."

Guzik said the TTCT test uses prompts that mimic real-life creative tasks. For instance, can you think of new uses for a product or improve this product?

"Let's say it's a basketball," he said. "Think of as many uses of a basketball as you can. You can shoot it in a hoop and use it in a display. If you force yourself to think of new uses, maybe you cut it up and use it as a planter. Or with a brick you can build things, or it can be used as a paperweight. But maybe you grind it up and reform it into something completely new."

Guzik had some expectation that ChatGPT would be good at creating a lot of ideas (fluency), because that's what generative AI does. And it excelled at responding to the prompt with many ideas that were relevant, useful and valuable in the eyes of the evaluators.

He was more surprised at how well it did generating original ideas, which is a hallmark of human imagination. The test evaluators are given lists of common responses for a prompt -- ones that are almost expected to be submitted. However, the AI landed in the top percentile for coming up with fresh responses.

"At the conference, we learned of previous research on GPT-3 that was done a year ago," Guzik said. "At that time, ChatGPT did not score as well as humans on tasks that involved original thinking. Now with the more advanced GPT-4, it's in the top 1% of all human responses."

With AI advances speeding up, he expects it to become a key tool for the world of business going forward and a significant new driver of regional and national innovation.

"For me, creativity is about doing things differently," Guzik said. "One of the definitions of entrepreneurship I love is that to be an entrepreneur is to think differently. So AI may help us apply the world of creative thinking to business and the process of innovation, and that's just fascinating to me."

He said the UM College of Business is open to teaching about AI and incorporating it into coursework.

"I think we know the future is going to include AI in some fashion," Guzik said. "We have to be careful about how it's used and consider needed rules and regulations. But businesses already are using it for many creative tasks. In terms of entrepreneurship and regional innovation, this is a game changer."

Researchers calculate economic value of temporary carbon reduction with 'Social Value of Offsets' formula

 A new study identifies how to calculate the economic value of temporarily reducing carbon emissions through carbon offsetting.

The Social Value of Offsets (SVO) is an economic framework that will help policymakers calculate how much carbon should be stored in temporary offsets to make it equivalent to a permanent CO2 emission.

Using the SVO metric the researchers estimate that an offset sequestering one ton of carbon for 50 years is equivalent to between 0.3 to 0.5 tons permanently locked away, taking into account a range of factors for different risks, permanence and climate scenarios.

Offsets are a key part of Paris-compliant net zero strategies, but many offsetting projects fail and there is never a guarantee on how long an offset will sequester carbon for -- making it difficult to measure the economic damage avoided.

The study, published in Nature, sets out the risks and uncertainties of offsetting, which occur due to the unregulated nature of the global offsets market.

Risk factors to projects in tropical forests, for example, can include the lack of strong institutions on the ground to monitor, enforce and account for emissions sequestered, as well as the possibility of fires and disease.

There are also risks in how emissions reductions are reported as well that of 'non-additionality' -- when emissions reductions would have happened irrespective of the offsetting.

Other frameworks count the physical units of carbon but SVO is unique in that it is an economic framework where the value of temporary emissions reductions is measured as the value of the damages avoided to the economy during the length of the offsetting project.

The researchers say this will potentially make it easier to compare offsetting schemes, allowing anyone offsetting their carbon emissions to be able to weigh up the risks involved and decide how much carbon they would need to offset in temporary schemes to make up for a permanent carbon emission.

Professor Ben Groom, Dragon Capital Chair in Environmental Economics at the University of Exeter Business School, said: "Our analysis shows that a carbon emission today which is offset by a temporary project can be thought of as a postponed emission with the same warming effect when the project ends, but with less warming during the project.

"The Social Value of Offsets (SVO) stems from the value of delaying emissions and damages, and this depends on how impermanent, risky or additional they are. Valuing offsets using the SVO then provides a means of comparing offsets with different qualities in terms of the economic damages avoided."

Professor Groom explains why delaying emissions is important, both in an economic and physical sense. "With a project that stores carbon and releases it 50 years later, the net carbon reduction is always going to be zero, so some may say it's as if it never happened."

"But what that ignores is the flow of damages that you've avoided in the meantime, which could be important, because certain responses to climate change, like the melting of the ice caps, are responsive, depending on how long temperatures have been at a particular level.

"Delaying emissions is also important because economic processes could be happening in the background that make carbon removal cheaper in the future so offsetting could act as a temporary solution allowing the action point to be delayed until a time when it is cheaper to act.

"The question we're answering with SVO is how valuable this temporary period in which you avoid damages is."

The IPCC has previously noted that meeting the objectives of the Paris Agreement will require some offsetting, though some organisations suggest that offsetting should be largely avoided due to the unregulated, impermanent and risky nature of the offset market.

However, this study illustrates that in principle delaying emissions, even when offsetting projects are temporary and risky, is valuable in economic terms.

The economists believe the SVO metric can play an important role in appraising net-zero climate policy and harmonising the offset market, and has policy applications beyond the valuation of offsets.

These include calculating the benefits-to-cost ratio of an offset or any temporary carbon storage solution allowing for comparison to alternative technologies for mitigating climate change.

The SVO formula can also be applied to Life-Cycle Analysis of biofuels as well as used to calculate the price of carbon debt, using the rule of thumb that a company that emits a ton of carbon today and commits to a permanent removal in 50 years' time will pay 33% of the carbon price today to cover the damages of temporary atmospheric storage.

The Social Value of Offsets, by Professor Ben Groom, Dragon Capital Chair in Environmental Economics at the University of Exeter Business School and Professor Frank Venmans from the Grantham Research Institute on Climate Change and the Environment at LSE, is published in Nature.

GPT detectors can be biased against non-native English writers

 In a peer-reviewed opinion paper publishing July 10 in the journal Patterns, researchers show that computer programs commonly used to determine if a text was written by artificial intelligence tend to falsely label articles written by non-native language speakers as AI-generated. The researchers caution against the use of such AI text detectors for their unreliability, which could have negative impacts on individuals including students and those applying for jobs.

"Our current recommendation is that we should be extremely careful about and maybe try to avoid using these detectors as much as possible," says senior author James Zou, of Stanford University. "It can have significant consequences if these detectors are used to review things like job applications, college entrance essays or high school assignments."

AI tools like OpenAI's ChatGPT chatbot can compose essays, solve science and math problems, and produce computer code. Educators across the U.S. are increasingly concerned about the use of AI in students' work and many of them have started using GPT detectors to screen students' assignments. These detectors are platforms that claim to be able to identify if the text is generated by AI, but their reliability and effectiveness remain untested.

Zou and his team put seven popular GPT detectors to the test. They ran 91 English essays written by non-native English speakers for a widely recognized English proficiency test, called Test of English as a Foreign Language, or TOEFL, through the detectors. These platforms incorrectly labeled more than half of the essays as AI-generated, with one detector flagging nearly 98% of these essays as written by AI. In comparison, the detectors were able to correctly classify more than 90% of essays written by eighth-grade students from the U.S. as human-generated.

Zou explains that the algorithms of these detectors work by evaluating text perplexity, which is how surprising the word choice is in an essay. "If you use common English words, the detectors will give a low perplexity score, meaning my essay is likely to be flagged as AI-generated. If you use complex and fancier words, then it's more likely to be classified as human written by the algorithms," he says. This is because large language models like ChatGPT are trained to generate text with low perplexity to better simulate how an average human talks, Zou adds.

As a result, simpler word choices adopted by non-native English writers would make them more vulnerable to being tagged as using AI.

The team then put the human-written TOEFL essays into ChatGPT and prompted it to edit the text using more sophisticated language, including substituting simple words with complex vocabulary. The GPT detectors tagged these AI-edited essays as human-written.

"We should be very cautious about using any of these detectors in classroom settings, because there's still a lot of biases, and they're easy to fool with just the minimum amount of prompt design," Zou says. Using GPT detectors could also have implications beyond the education sector. For example, search engines like Google devalue AI-generated content, which may inadvertently silence non-native English writers.

While AI tools can have positive impacts on student learning, GPT detectors should be further enhanced and evaluated before putting into use. Zou says that training these algorithms with more diverse types of writing could be one way to improve these detectors.

Efficient discovery of improved energy materials by a new AI-guided workflow

 Scientists of the NOMAD Laboratory at the Fritz Haber Institute of the Max Planck Society recently proposed a workflow that can dramatically accelerate the search for novel materials with improved properties. They demonstrated the power of the approach by identifying more than 50 strongly thermally insulating materials. These can help alleviate the ongoing energy crisis, by allowing for more efficient thermoelectric elements, i.e., devices able to convert otherwise wasted heat into useful electrical voltage.

Discovering new and reliable thermoelectric materials is paramount for making use of the more than 40% of energy given off as waste heat globally and help mitigate the growing challenges of climate change. One way to increase the thermoelectric efficiency of a material is to reduce its thermal conductivity, κ, and thereby maintaining the temperature gradient needed to generate electricity. However, the cost associated with studying these properties limited the computational and experimental investigations of κ to only a minute subset of all possible materials. A team of the NOMAD Laboratory recently made efforts to reduce these costs by creating an AI-guided workflow that hierarchically screens out materials to efficiently find new and better thermal insulators.

The work recently published in npj Computational Materials proposes a new way of using Artificial Intelligence (AI) to guide the high-throughput search for new materials. Instead of using physical/chemical intuition to screen out materials based on general, known or suspected trends, the new procedure learns the conditions that lead to the desired outcome with advanced AI methods. This work has the potential to quantify the search for new energy materials and increase the efficiency of these searches.

The first step in designing these workflows is to use advanced statistical and AI methods to approximate the target property of interest, κ in this case. To this end, the sure-independence screening and sparsifying operator (SISSO) approach is used. SISSO is a machine learning method that reveals the fundamental dependencies between different materials properties from a set of billions of possible expressions. Compared to other "black-box" AI models, this approach is similarly accurate, but additionally yields analytic relationships between different material properties. This allows us to apply modern feature importance metrics to shed light on which material properties are the most important. In the case of κ, these are the molar volume, Vm; the high-temperature limit Debye Temperature, θD,∞; and the anharmonicity metricfactor, σA.

Furthermore, the described statistical analysis allows to distill out rule-of-thumbs for the individual features that enable to a priori estimate the potential of material to be a thermal insulator. Working with the three most important primary features hence allowed to create AI-guided computational workflows for discovering new thermal insulators. These workflows use state-of-the-art electronic structure programs to calculate each of the selected features. During each step materials were screened out that are unlikely to be good insulators based on their values of Vm, θD,∞, and σA. With this, it is possible to reduce the number of calculations needed to find thermally insulating materials by over two orders of magnitude. In this work, this is demonstrated by identifying 96 thermal insulators (κ < 10 Wm-1K-1) in an initial set of 732 materials. The reliability of this approach was further verified by calculating κ for 4 of these predictions with highest possible accuracy.

Besides facilitating the active search for new thermoelectric materials, the formalisms proposed by the NOMAD team can be also applied to solve other urgent material science problems.Scientists of the NOMAD Laboratory at the Fritz Haber Institute of the Max Planck Society recently proposed a workflow that can dramatically accelerate the search for novel materials with improved properties. They demonstrated the power of the approach by identifying more than 50 strongly thermally insulating materials. These can help alleviate the ongoing energy crisis, by allowing for more efficient thermoelectric elements, i.e., devices able to convert otherwise wasted heat into useful electrical voltage.

Discovering new and reliable thermoelectric materials is paramount for making use of the more than 40% of energy given off as waste heat globally and help mitigate the growing challenges of climate change. One way to increase the thermoelectric efficiency of a material is to reduce its thermal conductivity, κ, and thereby maintaining the temperature gradient needed to generate electricity. However, the cost associated with studying these properties limited the computational and experimental investigations of κ to only a minute subset of all possible materials. A team of the NOMAD Laboratory recently made efforts to reduce these costs by creating an AI-guided workflow that hierarchically screens out materials to efficiently find new and better thermal insulators.

The work recently published in npj Computational Materials proposes a new way of using Artificial Intelligence (AI) to guide the high-throughput search for new materials. Instead of using physical/chemical intuition to screen out materials based on general, known or suspected trends, the new procedure learns the conditions that lead to the desired outcome with advanced AI methods. This work has the potential to quantify the search for new energy materials and increase the efficiency of these searches.

The first step in designing these workflows is to use advanced statistical and AI methods to approximate the target property of interest, κ in this case. To this end, the sure-independence screening and sparsifying operator (SISSO) approach is used. SISSO is a machine learning method that reveals the fundamental dependencies between different materials properties from a set of billions of possible expressions. Compared to other "black-box" AI models, this approach is similarly accurate, but additionally yields analytic relationships between different material properties. This allows us to apply modern feature importance metrics to shed light on which material properties are the most important. In the case of κ, these are the molar volume, Vm; the high-temperature limit Debye Temperature, θD,∞; and the anharmonicity metricfactor, σA.

Furthermore, the described statistical analysis allows to distill out rule-of-thumbs for the individual features that enable to a priori estimate the potential of material to be a thermal insulator. Working with the three most important primary features hence allowed to create AI-guided computational workflows for discovering new thermal insulators. These workflows use state-of-the-art electronic structure programs to calculate each of the selected features. During each step materials were screened out that are unlikely to be good insulators based on their values of Vm, θD,∞, and σA. With this, it is possible to reduce the number of calculations needed to find thermally insulating materials by over two orders of magnitude. In this work, this is demonstrated by identifying 96 thermal insulators (κ < 10 Wm-1K-1) in an initial set of 732 materials. The reliability of this approach was further verified by calculating κ for 4 of these predictions with highest possible accuracy.

Besides facilitating the active search for new thermoelectric materials, the formalisms proposed by the NOMAD team can be also applied to solve other urgent material science problems.

Picturing where wildlands and people meet at a global scale

 Researchers led by a team at the University of Wisconsin-Madison have created the first tool to map and visualize the areas where human settlements and nature meet on a global scale. The tool, which was part of a study recently published in Nature, could improve responses to environmental conflicts like wildfires, the spread of zoonotic diseases and loss of ecosystem biodiversity.

These areas where people and wildlands meet are called the wildland-urban interface, or WUI for short. More technically, a WUI (pronounced "woo-ee") describes anywhere that has at least one house per 40 acres and is also 50% covered by wildland vegetation such as trees, shrubland, grassland, herbaceous wetland, mangroves, moss and lichen.

Franz Schug, a postdoctoral researcher in the Department of Forest and Wildlife Ecology at UW-Madison, explains that the areas were initially used by the U.S. Forest Service to assist with wildfire management in the Western United States.

Areas defined as WUI cover only about 4.7% of land on Earth, but about half of the human population lives within them. Many people enjoy living in these places because they like to be near the amenities of nature, explains Volker Radeloff, a professor of forest and wildlife ecology at UW-Madison.

"It reflects an affinity of people to nature, which is a good thing. If people said in general, 'No, we rather not be anywhere near a forest,' I'd be more worried with that," Radeloff says.

But these areas are also hot spots for environmental conflicts like wildfires, the spread of diseases from animals, habitat fragmentation and loss of biodiversity. While climate change is projected to increase the potential environmental conflict in the WUI, population growth increases the frequency in which humans and wildlands come into contact in many places. Knowing where both is likely to happen globally is important for planning for the future.

Yet, the WUI has only been prominently described in the United States and a few other developed countries. Schug saw a gap in the research. He set out to investigate WUIs' worldwide distribution, though mapping the high-resolution, global view required him to wrangle and make sense of a lot of information.

"I think the greatest challenge is just the amount of data that went into this," he says. "We have two servers in the basement [of the lab building] that were reactivated for that purpose. I think the whole thing covers several terabytes of data processing."

After setting up the computer program, it took three months to run through all the data, flagging the regions that qualify as a WUI. The land cover and building data they fed the computer was sourced from publicly available databases and stored on large servers.

Schug was able to record previously undocumented WUI in eastern Asia, East Africa and parts of South America.

Unsurprisingly, WUI around the world don't all look the same or have the same kinds of ecosystems. If the goal is to be able to inform better management practices, Schug realized he would need to provide more context on what the kinds landscapes made up these WUIs. After all, managing rain forests is very different from managing grasslands.

"Especially in these biomes, where other studies predict that most likely climate change will have an impact on fire severity and fire frequencies, where a lot of people live, they're definitely areas that will be a future interest," Schug says.

The WUI is already being leveraged in countries like Poland, Argentina and Portugal, but Radeloff and Schug see this global view as a tool that can help land managers around the world know where they need to keep an eye on in the future.

As the climate changes, some of these biomes will see more wildfires, more people and animals coming into contact with each other for the first time and more opportunities for the spread of disease and ecosystem disruption.

Schug hopes this work will inspire further regionalized research around the WUIs they've documented, empowering local land managers to better prepare for change.

Children's IQs not diminished by concussion, study suggests

 The angst parents feel when their children sustain injuries is surely one of the universal conditions of parenthood. That anxiety is heightened greatly when those injuries involve concussions. But a new study led out of the University of Calgary, published today in the medical journal Pediatrics, may set worried parental minds slightly at ease.

The findings -- taken from emergency room visits in children's hospitals in Canada and the United States -- show that IQ and intelligence is not affected in a clinically meaningful way by pediatric concussions.

The study compares 566 children diagnosed with concussion to 300 with orthopedic injuries. The children range in age from eight to 16 and they were recruited from two cohort studies. The Canadian cohort encompasses data collected from five children's hospital emergency rooms, including Alberta Children's Hospital in Calgary, along with those in Vancouver, Edmonton, Ottawa, and Montreal (CHU Sainte-Justine). In the Canadian hospitals, patients completed IQ tests three months postinjury.

The U.S. cohort was conducted at two children's hospitals in Ohio, wherein patients completed IQ tests three to 18 days, postinjury.

"Obviously there's been a lot of concern about the effects of concussion on children, and one of the biggest questions has been whether or not it affects a child's overall intellectual functioning," says Dr. Keith Yeates, PhD, a professor in UCalgary's Department of Psychology and senior author of the Pediatrics paper. Yeates is a renowned expert on the outcomes of childhood brain disorders, including concussion and traumatic brain injuries.

"The data on this has been mixed and opinions have varied within the medical community," says Yeates. "It's hard to collect big enough samples to confirm a negative finding. The absence of a difference in IQ after concussion is harder to prove than the presence of a difference."

Combining the Canadian and U.S. cohorts gave the Pediatrics study an abundant sample and it allowed Yeates and his co-authors -- from universities in Edmonton, Montreal, Vancouver, Ottawa, Atlanta, Utah, and Ohio, along with Calgary's Mount Royal University -- to test patients with a wide range of demographics and clinical characteristics.

"We looked at socioeconomic status, patient sex, severity of injuries, concussion history, and whether there was a loss of consciousness at the time of injury," says Yeates. "None of these factors made a difference. Across the board, concussion was not associated with lower IQ."

The children with concussion were compared to children with orthopedic injuries other than concussion to control for other factors that that might affect IQ, such as demographic background and the experience of trauma and pain. This allowed the researchers to determine whether the children's IQs were different than what would be expected minus the concussion.

The findings of the study are important to share with parents, says Dr. Ashley Ware, PhD, a professor at Georgia State University and lead author of the paper. While the Pediatrics research was underway, Ware was a Killam Postdoctoral Fellow at UCalgary, where Yeates was her supervisor.

"Understandably, there's been a lot of fear among parents when dealing with their children's concussions," Ware says. "These new findings provide really good news, and we need to get the message to parents."

Dr. Stephen Freedman, PhD, co-author of the paper, a professor of pediatrics and emergency medicine at the Cumming School of Medicine, agrees. "It's something doctors can tell children who have sustained a concussion, and their parents, to help reduce their fears and concerns," says Freedman. "It is certainly reassuring to know that concussions do not lead to alterations in IQ or intelligence."

Another strength of the Pediatrics research is that incorporates the two cohort studies, one testing patients within days of their concussions and the other after three months.

"That makes our claim even stronger," says Ware. "We can demonstrate that even in those first days and weeks after concussion, when children do show symptoms such as a pain and slow processing speed, there's no hit to their IQs. Then it's the same story three months out, when most children have recovered from their concussion symptoms. Thanks to this study we can say that, consistently, we would not expect IQ to be diminished from when children are symptomatic to when they've recovered."

She adds: "It's a nice 'rest easy' message for the parents."

Picturing where wildlands and people meet at a global scale

 Researchers led by a team at the University of Wisconsin-Madison have created the first tool to map and visualize the areas where human settlements and nature meet on a global scale. The tool, which was part of a study recently published in Nature, could improve responses to environmental conflicts like wildfires, the spread of zoonotic diseases and loss of ecosystem biodiversity.

These areas where people and wildlands meet are called the wildland-urban interface, or WUI for short. More technically, a WUI (pronounced "woo-ee") describes anywhere that has at least one house per 40 acres and is also 50% covered by wildland vegetation such as trees, shrubland, grassland, herbaceous wetland, mangroves, moss and lichen.

Franz Schug, a postdoctoral researcher in the Department of Forest and Wildlife Ecology at UW-Madison, explains that the areas were initially used by the U.S. Forest Service to assist with wildfire management in the Western United States.

Areas defined as WUI cover only about 4.7% of land on Earth, but about half of the human population lives within them. Many people enjoy living in these places because they like to be near the amenities of nature, explains Volker Radeloff, a professor of forest and wildlife ecology at UW-Madison.

"It reflects an affinity of people to nature, which is a good thing. If people said in general, 'No, we rather not be anywhere near a forest,' I'd be more worried with that," Radeloff says.

But these areas are also hot spots for environmental conflicts like wildfires, the spread of diseases from animals, habitat fragmentation and loss of biodiversity. While climate change is projected to increase the potential environmental conflict in the WUI, population growth increases the frequency in which humans and wildlands come into contact in many places. Knowing where both is likely to happen globally is important for planning for the future.

Yet, the WUI has only been prominently described in the United States and a few other developed countries. Schug saw a gap in the research. He set out to investigate WUIs' worldwide distribution, though mapping the high-resolution, global view required him to wrangle and make sense of a lot of information.

"I think the greatest challenge is just the amount of data that went into this," he says. "We have two servers in the basement [of the lab building] that were reactivated for that purpose. I think the whole thing covers several terabytes of data processing."

After setting up the computer program, it took three months to run through all the data, flagging the regions that qualify as a WUI. The land cover and building data they fed the computer was sourced from publicly available databases and stored on large servers.

Schug was able to record previously undocumented WUI in eastern Asia, East Africa and parts of South America.

Unsurprisingly, WUI around the world don't all look the same or have the same kinds of ecosystems. If the goal is to be able to inform better management practices, Schug realized he would need to provide more context on what the kinds landscapes made up these WUIs. After all, managing rain forests is very different from managing grasslands.

"Especially in these biomes, where other studies predict that most likely climate change will have an impact on fire severity and fire frequencies, where a lot of people live, they're definitely areas that will be a future interest," Schug says.

The WUI is already being leveraged in countries like Poland, Argentina and Portugal, but Radeloff and Schug see this global view as a tool that can help land managers around the world know where they need to keep an eye on in the future.

As the climate changes, some of these biomes will see more wildfires, more people and animals coming into contact with each other for the first time and more opportunities for the spread of disease and ecosystem disruption.

Schug hopes this work will inspire further regionalized research around the WUIs they've documented, empowering local land managers to better prepare for change.

Ultra-processed foods largely missing from US food policy

 Ultra-processed foods -- including industrially produced packaged snacks, fruit-flavored drinks, and hot dogs -- have been linked to health issues ranging from weight gain to certain cancers. So where are the food policies helping Americans to steer clear of these foods?

A new study published in the American Journal of Preventive Medicine finds that only a small number of U.S. policies consider ultra-processed foods, lagging behind countries such as Belgium, Brazil, and Israel.

"In some countries, ultra-processed foods have been directly integrated into national dietary guidelines and school food programs, but in the U.S., few policies directly target ultra-processed foods," said Jennifer Pomeranz, associate professor of public health policy and management at NYU School of Global Public Health and the first author of the study.

After decades of focusing on single nutrients such as protein, fat, and carbohydrates in nutrition science and food policy, a growing body of evidence shows that there is more to dietary quality than nutrients.

"It's clear that the extent of processing of a food can influence its health effects, independent of its food ingredients or nutrient contents. Ultra-processed foods generally contain 'acellular nutrients' -- nutrients lacking any of the natural intact food structure of the source ingredient -- and other industrial ingredients and additives that together can increase risk of weight gain, diabetes, and other chronic diseases," said study co-author Dariush Mozaffarian, the Jean Mayer Professor of Nutrition at the Friedman School of Nutrition Science and Policy at Tufts.

Only a few countries around the world directly regulate ultra-processed foods, but those that do have limited its consumption in schools and recommend eating less ultra-processed food in dietary guidelines. The U.S. Dietary Guidelines for Americans, which inform the country's food and nutrition policies, do not currently mention ultra-processed food. However, the scientific advisory committee for the 2025-2030 U.S. Dietary Guidelines has been tasked with evaluating research related to ultra-processed foods consumption as it relates to weight gain.

To understand how U.S. policymakers have already addressed ultra-processed foods in policies, the researchers gathered all federal and state statutes, bills, resolutions, regulations, proposed rules, and Congressional Research Services reports related to "highly processed" and "ultra-processed" food.

They identified only 25 policies -- eight at the federal level and 17 at the state -- that were proposed or passed between 1983 and 2022. The vast majority (22 of 25) were proposed or passed since 2011, showing that U.S. policy making on ultra-processed foods is quite recent.

The U.S. policies on ultra-processed foods tend to mention them as contrary to healthy diets. Most policies had to do with healthy eating for children, including limiting ultra-processed foods in schools and teaching kids about nutrition. Another common theme was the relatively higher price of healthy food versus ultra-processed foods. Only one policy (a Massachusetts school food bill) actually defined ultra-processed foods, and three policies sought to address the broader food environment by providing incentives to small retailers to stock healthy foods.

"The emerging policy language in the U.S. on ultra-processed foods is consistent with international policies on the topic. We would urge a more robust discussion and consideration of ultra-processed foods for future policymaking," added Pomeranz. "The United States should consider processing levels in school food policies -- especially to update the 'Smart Snack' rules -- and to ensure the U.S. Dietary Guidelines reflect the evidence on ultra-processed foods and health."

Introducing the Climate Solutions Explorer

 IIASA recently launched the Climate Solutions Explorer -- a comprehensive resource that visualizes and presents vital data about climate mitigation, climate impacts, vulnerabilities, and risks arising from development and climate change.

The website utilizes the latest data and state-of-the-art models to assess future trends related to development- and climate-induced challenges. By offering up-to-date information on climate mitigation and impacts, the Climate Solutions Explorer aims to be a go-to platform for anyone interested in accessing the latest research on climate change and net-zero mitigation pathways.

The Climate Solutions Explorer is the result of a long-standing collaboration and contributions from various sources within and external to the ENGAGE project -- a global consortium consisting of nearly 30 partners, coordinated by IIASA and co-led by several other institutions. The project, which has been running since September 2019 and will conclude in December this year, aims to explore the feasibility of pathways that align with the objectives of the Paris Agreement.

So, what can you expect from the Climate Solutions Explorer website?

"The platform offers a diverse range of content, including an interactive map that visualizes climate change impacts, national and regional data dashboards showcasing impacts and mitigation pathways, and articles covering a wide array of climate-related topics and countries. The website also provides publicly available data, allowing users to delve deep into their preferred areas of exploration," explains Edward Byers, a researcher in the IIASA Energy, Climate, and Environment Program and coordinator of the website.

One particularly interesting feature of the website is the "Net Zero Stories" section, which features narratives written by local experts. These stories document national transitions towards sustainable, net-zero societies and offer insightful analyses on the trade-offs and co-benefits associated with these transformations. With an understanding that sustainable transitions have commonalities but also regional variations, the Net Zero Stories shed light on the unique challenges and opportunities faced by different countries.

For those interested in specific countries, the Climate Solutions Explorer offers national dashboards that consider variables such as socioeconomics, emissions, mitigation options, and climate impacts at varying levels of exposure and risk. This enables users to gain valuable insights into the climate landscape of specific countries and the potential implications of global warming.

"The launch of the Climate Solutions Explorer represents a significant step forward in our collective efforts to tackle climate change. By providing easy access to the latest data, cutting-edge models, and expert analysis, this comprehensive website empowers individuals, businesses, and policymakers to make informed decisions and contribute to a more sustainable future. Whether you're interested in understanding the impacts of climate change or exploring net-zero pathways, the Climate Solutions Explorer is your go-to resource for all things climate-related," Byers concludes.

Climate science is catching up to climate change with predictions that could improve proactive response

 In Africa, climate change impacts are experienced as extreme events like drought and floods. Through the Famine Early Warning Systems Network (which leverages expertise from USG science agencies, universities, and the private sector) and the IGAD Climate Prediction and Applications Center, it has been possible to predict and monitor these climatic events, providing early warning of their impacts on agriculture to support humanitarian and resilience programming in the most food insecure countries of the world.

Science is beginning to catch up with and even get ahead of climate change. In a commentary for the journal Earth's Future, UC Santa Barbara climate scientist Chris Funk and co-authors assert that predicting the droughts that cause severe food insecurity in the Eastern Horn of Africa (Kenya, Somalia and Ethiopia) is now possible, with months-long lead times that allow for measures to be taken that can help millions of the region's farmers and pastoralists prepare for and adapt to the lean seasons.

"We've gotten very good at making these predictions," said Funk, who directs UCSB's Climate Hazards Center, a multidisciplinary alliance of scientists who work to predict droughts and food shortages in vulnerable areas.

In the summer of 2020, the CHC predicted that climate change, interacting with naturally occurring La Niña events, would bring devastating sequential drought to the Eastern Horn of Africa. The region normally has two wet seasons a year -- spring and fall. An unprecedented five rainy seasons in a row failed. Eight months before each of those failures, the CHC anticipated droughts. Fortunately, agencies and other collaborators paid heed to those early warnings and were able to take effective actions, Funk said. Within the U.S. Agency for International Development (USAID), the forecasts helped motivate hundreds of millions of dollars in assistance for millions of starving people.

These efforts were a far cry from similar predictions of sequential droughts that the researchers, collaborating with the USAID-supported Famine Early Warning Systems Network, made for the same region ten years earlier. Predictions that went largely unheeded. "More than 250,000 Somalis died," Funk said. "It was just really horrible."

At the time, he said, the available forecasts weren't able to predict rainfall deficits in this region. While the models said East Africa would become wetter, observations showed substantial declines in the spring wet season. And to be fair, he added, the group's long-range weather prediction capabilities were still in their infancy. "We made an accurate forecast, but we didn't understand very well what was going on scientifically," Funk said. "Now, following our success in 2016/17, and extensive outreach efforts, the humanitarian relief community appreciates the value of our early warning systems."

In the intervening 10 years, the researchers have worked to discern and understand the broad, often distant mechanisms that drive drought in the Eastern Horn of Africa and create accurate, tailored forecasts for the region. They built on research showing that increased rainfall around Indonesia, caused by anthropogenic increases in sea surface temperatures, resulted in less moisture flowing on to the East African coast during the rainy months. These changes in moisture flows drive back-to-back droughts. But as climate change increases western Pacific sea surface temperatures, it becomes more and more possible to predict devastating water shortages.

"We've published about 15 scientific papers on this topic," Funk said, "and we've forecasted dry seasons in 2016-2017, which helped prevent a famine that year." As he discusses in his book "Drought, Flood, Fire (Cambridge University Press, 2021)," "climate change amplifies natural sea surface temperature variations, which opens the door to better forecasts."

In the new commentary and a longer paper currently at preprint stage, also coming out in Earth's Future, the co-authors highlight, respectively, the opportunities associated with these long range outlooks, and the physical mechanisms explaining the predictability.

"To reduce the impacts of climate extremes, we need to look for opportunities," said CHC Specialist and Operations Analyst Laura Harrison. "We need to pay attention to not just how climate is changing, but how these changes can support more effective predictions for droughts and for advantageous cropping conditions. As a community, we also need to foster communication about successful resilience strategies."

"Flooding still happens, drought still happens, people still get hurt, but we can try to reduce the harm."

With climate models that can predict extreme ocean states at eight-month lead times, and weather forecasts that can make projections at two weeks and at 45 days, CHC scientists and researchers now can provide actionable information to collaborators on the ground to help local farmers anticipate and plan for dry conditions.

"We're working with this group called Plant Village, who is providing agricultural advisories to millions of Kenyans, and helping them take actions that can help make their crops more drought-resistant," Funk said.

This proactivity is something Funk and collaborators hope will become a bigger part of climate change strategy for the Eastern Horn of Africa, as their models predict more of these drought-forming conditions in the region's future. A better local understanding of the mechanisms that result in droughts, and investments in early warning systems and adaptation measures, may initially be costly, they said, "but are relatively inexpensive when compared to post-impact, response-based alternatives such as humanitarian assistance and/or funding safety-net programs."

Education and participation can build trust and ultimately increase resilience. The CHC is building on what they learned in East Africa, and using it to feed partnerships in other parts of the world. In southern Africa, for example, they are collaborating with the Zimbabwe Meteorological Services Department and the Knowledge Impact Network to support the development of actionable climate services.

"Understanding that climate change makes extremes more frequent is really empowering because now we can try to anticipate those bad effects," Funk said. "Flooding still happens, drought still happens, people still get hurt, but we can try to reduce the harm."

Life on Earth didn't arise as described in textbooks

 No, oxygen didn't catalyze the swift blossoming of Earth's first multicellular organisms. The result defies a 70-year-old assumption about what caused an explosion of oceanic fauna hundreds of millions of years ago.

Between 685 and 800 million years ago, multicellular organisms began to appear in all of Earth's oceans during what's known as the Avalon explosion, a forerunner era of the more famed Cambrian explosion. During this era, sea sponges and other bizarre multicellular organisms replaced small single-celled amoeba, algae and bacteria, which until then, had had run of the planet for more than 2 billion years.

Up until now, it was believed that increased oxygen levels triggered the evolutionary arrival of more advanced marine organisms. This is being disproved by University of Copenhagen researchers working together with colleagues from Woods Hole Oceanographic Institute, the University of Southern Denmark and Lund University, among others.

By studying the chemical composition of ancient rock samples from an Omani mountain range, the researchers have been able to "measure" oxygen concentrations in the world's oceans from when these multicellular organisms appeared. Defying expectations, the result shows that Earth's oxygen concentrations had not increased. Indeed, levels remained 5-10 times lower than today, which is roughly how much oxygen there is at twice the height of Mount Everest.

"Our measurements provide a good picture of what average oxygen concentrations were in the world's oceans at the time. And it's apparent to us that there was no major increase in the amount of oxygen when more advanced fauna began to evolve and dominate Earth. In fact, there was somewhat of a slight decrease," says Associate Professor Christian J. Bjerrum, who has been quantifying the conditions surrounding the origin of life for the past 20 years.

Revises our understanding of life's origins

The new result puts to rest a 70-year research story that advances the centrality of higher oxygen concentrations in the development of more advanced life on our planet.

"The fact that we now know, with a high degree of certainty, that oxygen didn't control the development of life on Earth provides us with an entirely new story about how life arose and what factors controlled this success," says the researcher, adding:

"Specifically, it means that we need to rethink a lot of the things that we believed to be true from our childhood learning. And textbooks need to be revised and rewritten."

There remains much that the researchers don't know, as well as and a plethora of controversy. Therefore, Bjerrum hopes that the new result can spur other researchers around the world to reconsider their previous results and data in a new light.

"There are many research sections around the world, including in the United States and China, that have done lots of research on this topic, whose earlier results may shed important new details if interpreted on the basis that oxygen didn't drive the development of life," says the researcher.

Absence of oxygen may have aided development

So, if not extra oxygen, what triggered the era's explosion of life? Perhaps the exact opposite, explains the researcher:

"It's interesting that the explosion of multicellular organisms occurs at a time with low concentrations of atmospheric and oceanic oxygen. That indicates that organisms benefited from lower levels of oxygen and were able to develop in peace, as the water chemistry protected their stem cells naturally," says Christian J. Bjerrum.

According to the researcher, the same phenomenon has been studied in cancer research, in the stem cells of humans and other animals. Here, colleagues at Lund University observed that low oxygen levels are crucial for keeping stem cells under control until an organism decides that the cell ought to develop into a specific type of cell, such as a muscle cell.

"We know that animals and humans must be able to maintain low concentrations of oxygen in order to control their stem cells, and in so doing, develop slowly and sustainably. With too much oxygen, the cells will develop, and in the worst case, mutate wildly and perish. It is far from inconceivable that this mechanism applied back then," concludes Christian J. Bjerrum.

Fossils from Oman

In the new study, the researchers analysed rock samples from, among other places, the Oman Mountains in northern Oman. While quite high and very dry today, the mountains were on the seabed during the Avalon explosion's rapid blossoming of organism diversity.

The researchers have had their findings confirmed in fossils from three different mountain ranges around the world: the Oman Mountains (Oman), Mackenzie Mountains (NW Canada) and the Yangtze Gorges area of South China.

Over time, clay and sand from land are washed into the sea, where they settle into layers on the seabed. By going down through these layers and examining their chemical composition, researchers can get a picture of ocean chemistry at a particular geologic time.

The analyses were performed using Thallium and Uranium isotopes found in the mountains, which the researchers were able to extract data from, and in doing so, calculate oxygen levels from many hundreds of millions of years ago.

Flying reptiles had nurturing parental style

 Did the pterosaurs, flying reptiles from the days of the dinosaurs, practice parental care or not? New research by scientists from Ireland (University College Cork), China (Nanjing and Yunnan Universities) and the UK (University of Bristol and Queen Mary University of London) shows that pterosaurs were indeed caring parents -- but only the larger species.

This solves a long-standing conundrum. To be able to fly soon after hatching from the egg, a bird or pterosaur must have well-developed wings. Studies of smaller pterosaurs from the Jurassic showed that their babies already had large wings when they hatched and they could have wobbled into flight within a few days of birth.

But did this work for the later pterosaurs which were much larger in size? In the Cretaceous, pterosaurs usually had wingspans of 5 metres, and some even reached 10-15 metres, the size of a small glider.

"This was a difficult project," says the study leader, Dr Zixiao Yang from University College Cork (UCC). 'We needed examples of pterosaurs where we had at least one hatchling or very young specimen as well as adults so we could study their growth rates. But baby pterosaurs are really rare."

Dr Yang collaborated with Professor Baoyu Jiang from Nanjing University, Professor Michael Benton of University of Bristol, Professor Xu Xing of Yunnan University, and Professor Maria McNamara of UCC on the research.

"Luckily, we were able to use some classic specimens from the Jurassic of Europe and the Cretaceous of North America, together with new finds from China. By measuring the skulls, backbones, wings, and hind legs, we were able to test for differences in the relative growth of different parts of the body."

The research focussed on testing the allometry, or how the creatures' characteristics changed with size.

"We are all familiar with allometry in human babies, puppies and kittens -- their heads, eyes and knees are huge, and the rest of the body grows faster to get to adult proportions. It's the same with many animals, including dinosaurs and pterosaurs. The babies have cute faces, with short noses, big eyes, and big heads," Dr Yang said.

"The small, bird-sized, Jurassic pterosaurs were born with large wings and strong arms and legs, evidence that the babies could fly from birth. As they grew from baby to adult, their arms and legs showed negative allometry, meaning they started large and were then growing more slowly than the rest of the body."

"But it was different for the Cretaceous giants. They also started as small babies, but the key limb bones show positive allometry through growth, suggesting a very different developmental model."

"This means that the pterosaur giants had sacrificed low-input childcare to the need to grow huge eventually as adults. Minimal childcare makes sense in the early evolutionary history of these ancient reptiles because it saves energy. But to grow huge, the larger pterosaurs had a problem -- it basically took much longer to become an adult, and therefore parents needed to protect their young from accidents. The babies of all pterosaurs, large and small, were small because of the limitations of egg size. Investing in childcare by having non-flying babies was offset in evolutionary terms by allowing pterosaurs to evolve truly huge sizes."

"We see the same thing in birds and mammals today. Some birds fly very young, and of course some mammals like cattle and antelopes are on their feet the day they are born. But this kind of behaviour is risky for the babies because they are often clumsy and are easy targets for predators; it's costly also for the mother because the babies must have highly developed wings or legs at the point of birth. So, we see the same thing in extinct pterosaurs. They were restricted in maximum body size until the end of the Jurassic, at which point their parental care behaviour changed, and then they could achieve huge sizes."

Early humans were weapon woodwork experts, study finds

 A 300,000-year-old hunting weapon has shone a new light on early humans as woodworking masters, according to a new study.

State-of-the-art analysis of a double-pointed wooden throwing stick, found in Schöningen in Germany three decades ago, shows it was scraped, seasoned and sanded before being used to kill animals. The research indicates early humans' woodworking techniques were more developed and sophisticated than previously understood.

The findings, published today (Wednesday, 19 July) in PLOS ONE, also suggest the creation of lightweight weapons may have enabled group hunts of medium and small animals. The use of throwing sticks as hunting aids could have involved the entire community, including children.

Dr Annemieke Milks, of the University of Reading's Department of Archaeology, led the research. She said: "Discoveries of wooden tools have revolutionised our understanding of early human behaviours. Amazingly these early humans demonstrated an ability to plan well in advance, a strong knowledge of the properties of wood, and many sophisticated woodworking skills that we still use today.

"These lightweight throwing sticks may have been easier to launch than heavier spears, indicating the potential for the whole community to take part. Such tools could have been used by children while learning to throw and hunt."

Co-author Dirk Leder said: "The Schöningen humans used a spruce branch to make this aerodynamic and ergonomic tool. The woodworking involved multiple steps including cutting and stripping off the bark, carving it into an aerodynamic shape, scraping away more of the surface, seasoning the wood to avoid cracking and warping, and sanding it for easier handling."

High-impact weapon

Found in 1994, the 77cm-long stick is one of several different tools discovered in Schöningen, which includes throwing spears, thrusting spears and a second similarly sized throwing stick.

The double-pointed throwing stick -- analysed to an exceptionally high level of detail for this new study -- was most likely used by early humans to hunt medium-sized game like red and roe deer, and possibly fast-small prey including hare and birds that were otherwise difficult to catch. The throwing sticks would have been thrown rotationally -- similar to a boomerang -- rather than overhead like a modern-day javelin and may have enabled early humans to throw as far as 30 metres. Although lightweight, the high velocities at which such weapons can be launched could have resulted in deadly high-energy impacts.

The fine surface, carefully shaped points and polish from handling suggest this was a piece of personal kit with repeated use, rather than a quickly made tool that was carelessly discarded.

Principal investigator Thomas Terberger said: "The systematic analysis of the wooden finds of the Schöningen site financed by German Research Foundation provides valuable new insights and further exciting information on these early wooden weapons can be expected soon."

The well-preserved stick is on display at the Forschungsmuseum in Schöningen.