Controlled burning of coniferous forests helps prevent larger wildfires and thus reduces emissions of polluting smoke, according to a study published in Science. The study uses satellite data to estimate the severity of wildfires in California between 2000 and 2021, combined with estimates of fine particulate matter emitted by the fires. By simulating the prescribed burning of more than 2,000 km² of forest per year, the authors estimate a 10% reduction in the cumulative emission of harmful particles in California up to a decade later.

Six state-of-the-art large language models (LLMs) based on artificial intelligence (AI) can simulate human emotions such as fear, sadness, and anxiety, according to a study published in the journal The Lancet Digital Health. The authors clarify that these are metaphorical reactions on the part of the algorithms, but suggest that this could open new avenues for developing and testing conversational therapy techniques aimed at treating mental health disorders.

Rising sea levels have quadrupled the frequency of extreme events related to this phenomenon along coastlines since 1900. This is one of the conclusions of a study, which included Spanish participation, suggesting that climate change has already altered the risk of coastal flooding and highlighting the need to integrate these changes into adaptation and risk management strategies. More than 680 million people worldwide live in low-lying coastal regions, where small changes in sea level can significantly affect flood risk. The study is published in Nature Climate Change and aligns with another paper, published the same day in Science Advances, which states that since the 1970s, the number of days on which sea levels have exceeded annual averages has tripled.

The origin and the process by which eukaryotic cells arose remains one of the great unanswered questions in biology, with Lynn Margulis’s theories regarding the incorporation of a bacterium that would later become the mitochondrion marking a major turning point. Now, Spanish research carried out by IRB Barcelona and the Barcelona Supercomputing Center challenges this view. Without denying the role of mitochondria, it suggests that the process was longer and more complex than previously thought, stretching over hundreds of thousands of years. At least two other different bacteria contributed to the development of eukaryotic cells, and giant viruses appear to have acted as vehicles for genetic transfer. The findings, published in Nature, suggest a much more protracted and gradual process of exchange between microorganisms.

Formaldehyde is a preservative used on human tissue; inhaling it has harmful health effects and it is considered a human carcinogen. A study published in Occupational & Environmental Medicine shows that airborne concentrations of this compound in most pathological anatomy departments of the UK’s National Health Service (NHS) are rarely monitored and regularly exceed the occupational exposure limits set by the European Union (EU): seven out of 10 departments exceeded the eight-hour maximum exposure limit set by the EU.

An analysis based on Google Trends data collected between 2005 and 2025 showed that the proportion of menopause-related searches referring to commercial products and services increased by between 15 and 20 percentage points in the UK, Australia and the US. These findings suggest that people may increasingly be seeking non-clinical approaches to managing the menopause, not only for symptom relief but also for guidance, monitoring and support outside of clinical consultations. The study is published today in the journal JAMA Network Open.

A new United Nations (UN) report assesses the annual environmental costs of artificial intelligence (AI). According to the report, by 2030, if data centers were a country, their electricity consumption would be on par with that of France. As for carbon dioxide emissions, these could reach 400 million tons of CO₂ equivalent, comparable to the total emissions of the United Kingdom. The 9.3 trillion liters of water they use would cover the drinking water needs of the planet’s 8.1 billion people for 1.6 years. The report notes that the generation of high-resolution videos is at the top of AI’s energy consumption. Furthermore, it highlights the growing digital divide and environmental injustice between the nations that control AI systems and those that bear their environmental costs, particularly in the Global South.

The so-called ‘Iceman’, Ötzi, who lived approximately 5,300 years ago, was discovered in 1991 in the Ötztal Alps, on the border between Austria and Italy. His mummified remains were preserved at -6°C in a museum to replicate the conditions in which they were found. Now, a team from Italy has discovered that he contains communities of both ancient and modern microorganisms, some of which may be metabolically active or capable of replicating under the current preservation conditions, although, for the moment, no damage has been detected. According to the researchers, this demonstrates that “the ‘Iceman’ is not a static relic, but a dynamic biological interface.” The results are published in Microbiome. 

Countries’ current climate commitments fall short of the targets needed to limit global warming to 1.5 °C this century, with a shortfall of more than 5 billion tonnes of CO₂ per year by 2050. This is one of the conclusions of the third edition of the report The State of Carbon Dioxide Removal. To offset this shortfall, the report estimates that carbon dioxide removal would need to grow at a rate comparable to that of the fastest clean energy transitions, such as solar power or electric vehicles. The report highlights that the world removes around 2.2 billion tonnes of CO₂ from the atmosphere each year, almost entirely through land-based actions such as forest restoration. New technologies that use machinery or minerals to store carbon account for just 0.1% of total removal.

An article published in Brain Health proposes using the concept of the ‘criticome’ to refer to the sensory, motor, social, cultural and environmental information recorded from pregnancy up to the age of 25, which is the period of greatest brain plasticity. According to the authors, this concept reframes autism, schizophrenia and depression as developmental disorders rather than purely synaptic disorders. Besides, they say this approach would have implications for educational policy, mental health care and screen use, amongst other issues.