It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
Thursday, August 14, 2025
Specially adapted drones successfully use a "tap and go" approach to apply monitoring tags to whales, speeding up the process and avoiding human interference
Tagging method overview. A: Looking for whales. B: Launching the drone from the boat. C: Aligning the drone behind the whale prior to tag deployment. D: Tag deployment on the whale via “tap-and-go”. E: Drone return on the boat. F: Data recording on the whale. G: Tag retrieval. H: Data offload and tag reconditioning for the next deployment.
Credit: Vogt et al., 2025, PLOS One, CC-BY 4.0 (https://creativecommons.org/licenses/by/4.0/)
Specially adapted drones successfully use a "tap and go" approach to apply monitoring tags to whales, speeding up the process and avoiding human interference
Tourists explore the ‘Dome of the Cathedral’, the largest chamber in Grutas Tzabnah (Yucatán, Mexico), and the origin of Tzab06-1. The artificial well ‘La Noria’ now illuminates the cave.
A drought lasting 13 years and several others that each lasted over three years may have contributed to the collapse of the Classic Maya civilisation, chemical fingerprints from a stalagmite in a Mexican cave have revealed.
A detailed analysis of oxygen isotopes in the stalagmite allowed a team of researchers, led by the University of Cambridge, to determine rainfall levels for individual wet and dry seasons between 871 and 1021 CE, which overlaps with the Terminal Classic period of Maya civilisation. This is the first time it has been possible to isolate rainfall conditions for individual wet and dry seasons during the Terminal Classic, the time of societal decline historically referred to as the Maya collapse.
During the Terminal Classic, limestone Maya cities in the south were abandoned and dynasties were ended, as one of the ancient world’s great civilisations shifted north and lost much of its political and economic power.
The data contained within the stalagmite, from a cave in the Yucatán, showed that there were eight wet season droughts that lasted for at least three years during this period, with the longest drought lasting for 13 consecutive years.
This climate data aligns with existing historical and archaeological evidence: construction of monuments and political activity at several major northern Maya sites, including the famous city of Chichén Itzá, stopped at different times during this period of climate stress.
The accurately and precisely dated droughts provide a new framework for fine-grained analysis of the timing and dynamics of human-climate interactions in the region. The results are reported in the journal Science Advances.
“This period in Maya history has been a cause of fascination for centuries,” said lead author Dr Daniel H. James, who conducted the research while a PhD student at Cambridge’s Department of Earth Sciences. “There have been multiple theories as to what caused the collapse, such as changing trade routes, war or severe drought, based on the archaeological evidence the Maya left behind. But in the past few decades, we’ve started to learn quite a lot about what happened to the Maya and why, by combining the archaeological data with quantifiable climate evidence.”
Starting in the 1990s, researchers began to piece together climate records with those left by the Maya, such as the dates they recorded on key monuments, to show that a series of droughts during the Terminal Classic was a likely contributor to the massive socio-political upheaval in Maya society.
Now, James and his co-authors from the UK, US and Mexico have used the chemical fingerprints contained in stalagmites from a cave in the northern Yucatán to bring those droughts into much sharper focus.
Stalagmites form when water drips from the ceiling of a cave, and the minerals contained in the water grow into large deposits on the cave floor. By dating and analysing the layers of oxygen isotopes within the stalagmite, the researchers extracted highly detailed information about the climate in the Terminal Classic period. Earlier research has measured the oxygen isotopes contained in lake sediment to determine the severity of drought, but lake sediment does not contain enough detail to pinpoint climate conditions in any given year at a particular site.
“It hasn’t been possible to directly compare the history of individual Maya sites with what we previously knew about the climate record,” said James, who is now a postdoctoral researcher at University College London (UCL). “Lake sediment is great when you want to look at the big picture, but stalagmites allow us to access the fine-grained detail that we’ve been missing.”
Earlier research on stalagmites has determined annual average rainfall amounts during the Terminal Classic, but the Cambridge-led team have now been able to go further, and isolate information from individual wet and dry seasons, thanks to relatively thick (about 1mm) annual layers in the stalagmite used in this study. The specific oxygen isotopes in each layer are a proxy for wet season drought.
“Knowing the annual average rainfall doesn’t tell you as much as knowing what each individual wet season was like,” said James. “Being able to isolate the wet season allows us to accurately track the duration of wet season drought, which is what determines if crops succeed or fail.”
According to the information contained in the stalagmite, there were eight wet season droughts lasting for at least three years between 871 and 1021 CE. The longest drought of the period lasted for 13 years. Even with the water management techniques that the Maya had, a drought that long would have had major impacts on society.
The climate information contained in the stalagmite lines up with the dates inscribed by the Maya on their monuments. In the periods of prolonged and severe drought, date inscription at sites such as Chichén Itzá stopped entirely.
“This doesn’t necessarily mean that the Maya abandoned Chichén Itzá during these periods of severe drought, but it’s likely that they had more immediate things to worry about than constructing monuments, such as whether the crops they relied on would succeed or not,” said James.
The researchers say that stalagmites from this and other caves in the region could be vital in putting the puzzle of the Terminal Classic period together.
“In addition to what stalagmites can tell us about this period in Maya history, they might also be able to tell us about the frequency and severity of tropical storms, for instance,” said James. “As a case study for fine-grained comparisons between climate and historical data, it’s exciting being able to apply methods usually associated with the deeper past to relatively recent history.”
The research was supported in part by the National Geographic Society and the Leverhulme Trust.
Classic Maya Response to Multi-Year Seasonal Droughts in Northwest Yucatán, Mexico
Article Publication Date
13-Aug-2025
Daniel H. James, David Hodell, Ola Kwiecien, and Sebastian Breitenbach (L-R) at the Maya site of Labna in the Puuc region (Yucatán, Mexico), which was most likely abandoned during the Terminal Classic.
Credit Mark Brenner
Daniel H. James installs a drip rate monitor upon a flowstone in Grutas Tzabnah (Yucatán, Mexico) as part of the wider cave monitoring campaign.
Daniel H. James, Ola Kwiecien, and David Hodell (L-R) install a SYP drip water autosampler in Grutas Tzabnah (Yucatán, Mexico) to analyse seasonal changes in drip chemistry.
Credit
Sebastian Breitenbach
Research Alert: A genetic twist that sets humans apart
Research from scientists at University of California San Diego School of Medicine have shed new light on an age-old question: what makes the human brain unique?
The team’s discovery comes from their investigation of human-accelerated regions (HARs) — sections of the human genome that have accumulated an unusually high level of mutations as humans have evolved. There is a lot of scientific interest in HARs, as they are hypothesized to play an essential role in conferring human-specific traits, and also have links to neurodevelopmental disorders, such as autism.
One reason why scientists think that HARs confer human-specific traits is because they have undergone rapid changes in their genetic sequences since we split from our closest living relative—the chimpanzee—approximately 5 million years ago.
Now, UC San Diego researchers have identified one particular HAR—called HAR123—that appears to be instrumental in shaping the human brain.
The researchers found:
HAR123 itself is not a gene, but is instead a type of molecular “volume control" known as a transcriptional enhancer. Transcriptional enhancers control which genes are activated, how much they are activated, and at what times they are activated during an organism’s development.
Through its role as a transcriptional enhancer, HAR123 promotes the development of neural progenitor cells, the cells that give rise to the two main types of brain cells — neurons and glial cells.
HAR123 also influences the ratio of neurons and glial cells that form from neural progenitor cells.
Ultimately, HAR123 promotes a particularly advanced human trait called cognitive flexibility, or the ability to unlearn and replace previous knowledge.
In addition to providing new insights into the biology of the human brain, the results also offer a molecular explanation for some of the radical changes that have occurred in the human brain over the course of our evolution. This is supported, for example, by the authors’ finding that the human version of HAR123 exerts different molecular and cellular effects than the chimpanzee version in both stem cells and neuron precursor cells in a petri dish.
Further research is needed to more fully understand the molecular action of HAR123 and whether the human version of HAR123 does indeed confer human-specific neural traits. This line of research could lead us to a better understanding of the molecular mechanisms underlying many neurodevelopmental disorders, such as autism.
The study, published online in Science Advances, was led by Miles Wilkinson, Ph.D., distinguished professor, and Kun Tan, Ph.D., assistant professor, both within the Department of Obstetrics, Gynecology, & Reproductive Sciences at UC San Diego School of Medicine. Wilkinson is also affiliate faculty of the UC San Diego Institute for Genomic Medicine. The study was funded, in part, by grants from the National Institutes of Health and 10x Genomics. The authors declare no competing interests.
Researchers predict that future climatic change is likely to cause declines in reindeer abundances and their distribution at rates rarely seen over the last 21,000 years.
Reindeer, also known as caribou in North America, are an Ice Age species that have survived many episodes of Arctic warming. They are uniquely adapted to Arctic environments, where they regulate ecosystems and sustain the livelihoods of many Indigenous Peoples.
Despite being one of the most abundant herbivores in the Arctic, climate change has contributed to a loss of nearly two-thirds of their global abundance over the last three decades.
An international team of researchers, led by the University of Adelaide and University of Copenhagen, looked back 21,000 years and examined how reindeer responded to past climatic events, asking whether they will be able to cope in the future.
“Using fossils, ancient DNA and computer models, we reconstructed changes in the abundance and distribution of reindeer over the past 21,000 years at resolutions never done before, and we directly compared these to future predictions,” says lead investigator Dr. Elisabetta Canteri, from the University of Adelaide and University of Copenhagen.
“This revealed that populations of reindeer have experienced major declines during periods of rapid climate warming, but the losses expected in the coming decades due to future climate change are likely to be even more severe than those in the past.”
The research team identified populations in North America as being particularly vulnerable.
“Our forecasts show that these North American caribou populations are most at risk from climate warming, with declines of up to 80 per cent likely by 2100 unless there are major cuts to greenhouse gas emissions and increased investment in wildlife management and conservation,” says Associate Professor Damien Fordham, Deputy Director of the Environment Institute at the University of Adelaide, who co-led the research.
“These declines are likely to have far-reaching ecological implications that will further increase the vulnerability of caribou in North America and reindeer in Eurasia to climatic warming and other stressors.”
Reindeer and caribou help maintain plant diversity in the tundra by feeding on some plants and influencing how others grow, meaning that where they disappear, plant diversity is likely to decline.
“A reduction in tundra plant diversity resulting from the loss of reindeer and caribou will have many cascading effects, including reduction of carbon storage in Arctic soils,” says Professor Eric Post, from University of California Davis, who contributed to this research.
“Continued losses will likely further exacerbate climatic warming through release of soil carbon to the atmosphere, which of course would further threaten reindeer and caribou as well as ourselves.”
“For thousands of years, the wellbeing of our own species has benefitted directly from healthy reindeer and caribou populations. Now more than ever we need to ensure their wellbeing in turn.”
Associate Professor Fordham says the results of this research, published in Science Advances, show urgent action is required.
“Increasing investment in the management and conservation of reindeer and caribou populations, particularly in North America, where losses are forecast to be greatest, will benefit the persistence of this species and the services it provides to Arctic ecosystems and the communities that depend on them,” he says.
A new MSU study shows that simple, hands-on activities, such as writing letters and pointing out words in daily life, are the most effective way to build early reading skills. Both children with and without speech and/or language impairments experienced literacy gains from print-related activities; however, only children with typical learning development experienced benefits from shared book reading.
All children who spent more time on literacy games, both digital and analog, scored lower on early reading assessments.
The findings challenge the idea that more exposure to learning games always helps, raising important questions for parents, educators and developers about which strategies best support early literacy.
EAST LANSING, Mich. – When it comes to teaching preschoolers their ABCs, sticking with the basics might just be more effective. Despite the rise of digital tools and educational games, learning to read still begins with simple, hands-on work, such as writing letters and spotting words in everyday life.
New findings from Michigan State University researchers suggest that some popular approaches for learning may not be as practical as parents think. Preschoolers who played more literacy games scored lower on reading assessments, while those engaged in print-focused activities saw the most significant gains.
The study, published in the Journal of Research in Reading, was led by professors Lori Skibbe and Ryan Bowles in the Department of Human Development and Family Studies at the College of Social Science, as well as Nick Waters, a former postdoctoral researcher. Funding was supported by the U.S. Department of Education and the National Institutes of Health.
Study background and methodology
The home literacy environment represents an important but small period when children in preschool learn literacy skills outside the classroom. It often represents activities related to print and shared book reading.
To understand how home routines shape early reading, the researchers identified three common types of literacy activities: print-focused activities, which includes direct work with letters and words, such as writing names, pointing out print on signs or practicing letter sounds; shared book reading, including reading picture books aloud, going to the library or discussing stories; and literacy games, which includes digital or analog games like flashcards, apps or alphabet videos.
The study included more than 1,000 children between the ages of 3 and 6, with a diverse sample of families from across one Midwestern state. About 800 of the children had typical development, while over 200 had speech and/or language impairments.
Skibbe and Bowles assessed children’s literacy development using three foundational skills: letter-nameknowledge, recognizing and naming letters; letter-sound knowledge, identifying the sounds letters make; and phonological awareness, or understanding how words break down into sounds, such as rhyming or segmenting syllables.
Parents completed surveys about how often they engaged in various literacy-related activities at home, including writing letters, reading books and using educational games or apps.
Key findings and implications
There were several key findings. Print-focused activities consistently predicted stronger early literacy skills in all children studied. Children who spent more time on literacy games scored lower on reading assessments across both groups. So heavier use of games was associated with worse literacy outcomes, regardless of a child’s developmental background.
But for the variable of shared book reading, it was only a significant predictor for children without speech and/or language impairments. So while the structure of the home literacy environment is similar for all children, there should be special attention when it comes to shared reading for those with disabilities.
The research challenges the assumption that more exposure to learning tools automatically means better results. Instead, it highlights the need for intentional, hands-on approaches. This doesn’t mean digital learning tools should be avoided; rather, they should be used more for supplemental learning rather than as a primary tool.
What parents should know about games
There are a few possible reasons why some games may not be helping. For example, certain games prioritize entertainment over education, employing flashy visuals and sounds that distract from the development of key skills.
For other games, even if high-quality, they lack personal, hands-on instruction, such as practicing writing or identifying real-world print — skills that are especially critical for children with speech and/or language challenges.
Teaching children early reading skills does not require expensive tools or programs. Everyday interactions with print learning opportunities are the most important. There are specific tips and actions that parents can take to encourage learning:
Spot letters together by finding letters on street signs, food packaging or menus.
Encourage writing and have your child write their name, draw letters or label pictures.
Make reading interactive by pointing to words, talking about letter sounds and asking questions while reading books.
Parents should be mindful of introducing games when children might be struggling. Thoughtfully integrate digital learning tools for supplemental learning.
Print-focused routines are especially important for children with learning impairments.
Michigan State University has been advancing the common good with uncommon will for 170 years. One of the world’s leading public research universities, MSU pushes the boundaries of discovery to make a better, safer, healthier world for all while providing life-changing opportunities to a diverse and inclusive academic community through more than 400 programs of study in 17 degree-granting colleges.
The study included 100 professional athletes who participated in combat sports.
Growing up in under-resourced neighborhoods was linked to thinner areas of the brain—a possible early sign of neurodegeneration.
Athletes from highly disadvantaged neighborhoods had smaller brain volumes in areas important for movement and memory, including the thalamus, cerebellum and hippocampus.
This link remained even after accounting for factors such as race and ethnicity, income and number of fights.
The findings support a broader understanding of brain health—one that includes social and environmental influences, not just physical trauma.
For professional fighters, childhood disadvantage linked to more brain changes later
MINNEAPOLIS – Athletes who participate in combat sports like boxing and mixed martial arts and grow up in disadvantaged neighborhoods may be more likely to show signs of brain changes associated with neurodegeneration than athletes from affluent neighborhoods, according to a study published on August 13, 2025, in Neurology® Open Access, an official journal of the American Academy of Neurology.
The study does not prove that socioeconomic disadvantage causes more changes in the brain. It only shows an association.
“It is well-known that high-impact sports such as professional fighting are at a greater risk of repetitive head injuries,” said study author Brooke D. Conway Kleven, DPT, PhD, of the University of Nevada, Las Vegas. “We found that socioeconomic status may influence how the brain responds to these repetitive impacts. Stressors related to income, employment, education and housing quality may compound the risks of repeated head trauma. Athletes from marginalized or under-resourced communities may face a heavier burden when it comes to brain health.”
The study included 100 professional combat sport athletes, 14% of whom were female and 43% of whom identified as Black, American Indian/Alaska Native, Asian, Pacific Islander or two or more races. All participants had a minimum of 10 professional fights and were currently active or recently retired from competition. They were followed an average of five years and 20% developed thinking and memory problems.
Each participant had a magnetic resonance imaging (MRI) brain scan to assess brain structure. They also had annual check-ups to evaluate brain health.
Researchers looked at social factors that may impact health, including income, education and housing. To rank participants based on these factors, they used U.S. Census data and a measure called the Area Deprivation Index. Higher scores reflect greater disadvantage. Athletes were divided into three groups, those who grew up in neighborhoods with low, moderate or high disadvantage.
Researchers found that athletes from high-disadvantage neighborhoods had a thinner outer layer in certain areas of the brain, which can be an early sign of neurodegeneration. They also had smaller brain volumes in key areas: the thalamus was an average of 354 mm³ smaller and the cerebellar cortex was 2,478 mm³ smaller than in athletes from low-disadvantage neighborhoods, and the hippocampus volume was lower compared to those in moderately disadvantaged neighborhoods.
When researchers adjusted for high levels of a protein that is a hallmark of damage in the central nervous system, they found that volumes in the thalamus were about 60% lower in those from high-disadvantage neighborhoods than those in low-disadvantage neighborhoods.
“The findings support a broader understanding of brain health—one that considers not just training or fight history, but also the social and economic context in which people live,” Conway Kleven said. “Our study suggests that where someone grows up matters. Recognizing stressors can help inform more equitable approaches to protecting long-term brain health.”
A limitation of the study is that only athletes currently training or recently retired were included, not long-retired athletes, which could have led to a lower percentage of people with cognitive impairment.
Discover more about brain injury at BrainandLife.org, from the American Academy of Neurology. This resource also offers a magazine, podcast, and books that connect patients, caregivers and anyone interested in brain health with the most trusted information, straight from the world’s leading experts in brain health. Follow Brain & Life® on Facebook, X, and Instagram.
The American Academy of Neurology is the leading voice in brain health. As the world’s largest association of neurologists and neuroscience professionals with more than 40,000 members, the AAN provides access to the latest news, science and research affecting neurology for patients, caregivers, physicians and professionals alike. The AAN’s mission is to enhance member career fulfillment and promote brain health for all. A neurologist is a doctor who specializes in the diagnosis, care and treatment of brain, spinal cord and nervous system diseases such as Alzheimer's disease, stroke, concussion, epilepsy, Parkinson's disease, multiple sclerosis, headache and migraine.
