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)
Monday, June 15, 2026
Genomes from Oceania offer new clues to human evolution
A new Yale-led study provides one of the most detailed and comprehensive analyses to date of genetic variation in human populations in Oceania, filling a major gap in representation in genomics research.
Despite harboring remarkable diversity, populations in this vast region in the South Pacific historically have been overlooked in global human genetic studies, which have often focused largely on peoples of European descent, researchers say.
“The drastic underrepresentation of Oceanians limits our understanding of human evolution and could exacerbate health inequalities as genomic research is used to develop novel medical treatments” said the lead author Serena Tucci, assistant professor of anthropology in Yale’s Faculty of Arts and Sciences and the principal investigator of the Yale Human Evolutionary Genomics Laboratory. “To fill that gap, my research team embarked on a large-scale project to expand what is known about human genetic variation, including genetic variants inherited from extinct hominins.”
The study, published on June 11 in the journal Science, shows how the genes that ancient humans acquired after mating with extinct hominins continue to shape the biology, health, and survival of our species today.
For the study, the research team sequenced the genomes of 177 individuals across 12 distinct populations in different parts of Near Oceania — the southwestern portion of the Pacific region that includes Papua New Guinea, the Bismarck Archipelago, and the Solomon Islands — and analyzed them alongside a massive dataset of 1,284 previously published genomes from individuals worldwide.
By tracing the deep history of the Pacific’s earliest pioneers, who migrated to the region by at least 45,000 years ago, the researchers uncovered unprecedented insights into human evolutionary history and adaptation. For example, they discovered that ancestors of Near Oceanic populations mated with at least three distinct groups related to Denisovans — an enigmatic hominin group initially discovered from fossil fragments in Siberia.
“Previous studies showed that DNA inherited from extinct hominins, such as Neanderthals and Denisovans, survives, scattered, in the genomes of present-day human populations” Tucci said. “With this study we have moved beyond simply ‘resurrecting’ this DNA to showing how it actively turns genes on and off, which is game-changing. This DNA is not just a remnant of ancient liaisons; it continues to influence our biology today.”
Mating between ancient humans and Denisovans left a legacy of many genetic variants, including some that contribute to functions in present-day humans, the researcher said.
For the new study, the researchers used an advanced functional genomic technique known as a “massively parallel reporter assay” to physically test the functional consequences of these genetic variants and identified over 3,100 that alter gene expression. This analysis provided some of the largest-scale evidence for how specific, adaptive genetic variants inherited from Denisovans function inside humans today, the researchers say.
They found that a substantial proportion of these adaptive and functional variants affected the interferon-gamma signaling pathway, a vital component of the human immune system that defends against infectious pathogens.
“DNA from extinct hominins — Denisovans and Neanderthals — helped facilitate human adaptation to diverse environments that people encountered as they migrated into this region of the world,” said Patrick Reilly, first author of the study and associate research scientist in the Yale Human Evolutionary Genomics Laboratory in the Department of Anthropology. “Pathogens are one of the strongest selective pressures — environmental factors that affect our ability to survive — throughout human evolution. We find evidence that genes inherited from Denisovans bolstered immunity to viruses and bacteria ancient humans encountered in Near Oceania.”
The study also revealed that Denisovan DNA influences skeletal development. The researchers discovered adaptive variants inherited from Denisovans in a specific gene called TRPS1. This same gene has been under strong positive selection in central African rainforest hunter-gatherers and highland populations in Ecuador, showing how evolution can result in recurrent local adaptations in different regions of the world.
“While Denisovans vanished from the Earth thousands of years ago, this research proves that our histories remain deeply intertwined,” Tucci said.
Coauthors of the study include Daniela Tejada-Martinez, Samantha L. Miller, Audrey Tjahjadi, Chang Liu, and Alysa Pomer of the Yale Human Evolutionary Genomics Laboratory; Stephen Rong, Jared Akers, Margaret E. Prentice, and Steven K. Reilly of Yale School of Medicine; D. Andrew Merriwether of Binghamton University; Françoise R. Friedlaender and Jonathan S. Friedlaender of Temple University; and George Koki of Papua New Guinea Institute for Medical Research.
The research was supported by the National Institute of General Medical Sciences and the National Human Genome Research Institute of the National Institutes of Health.
Long-term isolation and archaic introgression shape functional genetic variation in Near Oceania
Article Publication Date
11-Jun-2026
One billion times the distance from the Earth to the sun: First global map of mycorrhizal fungi reveals true scale of underground networks across the planet
Society for the Protection of Underground Networks
Credit: Truth & Beauty / Moritz Stefaner Justin Stewart - SPUN
Mycorrhizal fungi form underground networks that sustain plant life and help regulate Earth’s climate by drawing carbon into soils. In a study published today in Science, an international team of researchers produced the first global maps estimating the distribution and mass of the Earth’s arbuscular mycorrhizal fungal networks. Published alongside an interactive visualization that helps reveal the scale of this underground fungal infrastructure, the research will help scientists and decision makers understand where these vital fungal systems are thriving and where they are threatened.
Researchers found:
Global topsoils contain ~110 quadrillion kilometers of arbuscular mycorrhizal fungal network – made up of tubular cells known as hyphae. This distance is almost a billion times the distance from the Earth to the sun.
Grassland ecosystems are home to an estimated ~40% of Earth’s arbuscular mycorrhizal fungal infrastructure. The flooded grasslands of South Sudan, the Everglades in Florida, and the Tibetan plateau have exceptionally high predicted network density.
AM fungal networks transport an estimated ~4 billion tons of CO2e into soils each year (equivalent to 11% of all human-related carbon-dioxide emissions).
On average, large-scale agricultural crop lands are predicted to be associated with ~50% lower network densities. While more work is needed to link specific farming practices to mycorrhizal health, scientists worry that less dense networks diminish a soils’ ability to store carbon, cycle nutrients, and resist stress.
Arbuscular mycorrhizal fungi (known as AM fungi) form symbiotic trade relationships with ~70% of plant species on Earth. The fungi provide nutrients and water in exchange for carbon produced by plants. As ecosystem engineers, these networks form a critical living infrastructure that draws carbon into soils and supports much of life on Earth. Last year, in Nature, researchers published global analyses of the diversity patterns of underground mycorrhizal fungal communities accompanied by a digital tool, the Underground Atlas, to help decision-makers locate predicted underground biodiversity hotspots. But until now, no-one has attempted to predict and visualize the physical density and global distribution of AM fungal networks.
The researchers assembled data on the density of AM networks from over 16,000 soil-cores collected across Earth. They developed machine-learning models that incorporated data layers from deserts and tundra to forests to predict network density in unsampled ecosystems. In collaboration with the Physics of Behavior group at research institute AMOLF, the team calibrated their model with robotic imaging of over 300,000 living AM fungal hyphae grown in the lab. Using these datasets, they estimate that AM fungal networks have a total length of ~110 quadrillion kilometers and a mass of ~300 megatons of carbon (4-6x the mass of all living humans).
“It is hard to overstate the importance and enormity of these fungi” said lead author Dr. Justin Stewart, with the Society for the Protection of Underground Networks (SPUN). “There could be up to 10 meters (32 feet) of mycorrhizal network in just a teaspoon of soil.”
Often called one of the Earth’s circulatory systems, mycorrhizal networks move carbon, water, and nutrients across underground ecosystems. In healthy soils, mycorrhizal networks can increase the foraging area of plant roots by up to 100 times, while providing > 80 percent of a plant’s phosphorous.
“With the emergence of new technologies in high-resolution imaging, machine-learning and robotics, we are starting to reveal what has long been hidden under our feet” said co-lead author, Dr. Corentin Bisot, an AMOLF biophysicist. “We are learning how the complex bodies of network-forming fungi transport nutrients and help regulate the climate.”
The team worked with award-winning data visualization designer Moritz Stefaner to build the Mycorrhizal Infrastructure Map. It is the first time the Earth’s fungal infrastructure has been seen at this scale and resolution (estimates are calculated for every 1km2 of terrestrial land, excluding ice caps and areas lacking enough data to predict). The underlying data are available to download for governments and decision-makers to begin monitoring the health of critical underground fungal communities.
Last year, several of the same authors published a cover story in Nature in which they described how mycorrhizal fungal networks and their plant partners build hyper-efficient supply chains to trade carbon and nutrients, measuring carbon flows inside these living transport systems that can reach speeds of up to 120 um/sec (if one was inside the network, these speeds would feel like ~400km/hr). The current study is a critical step towards understanding how carbon and nutrient flows unfold on a global scale.
The study also documented potential threats. Mycorrhizal densities across croplands are predicted to be roughly half those in wild ecosystems. Wild grassland ecosystems were found to contain ~40% of the world’s arbuscular mycorrhizal biomass. Yet grasslands are among Earth’s least protected ecosystems and are being transformed into farmlands four times faster than forests. This reinforces a finding published by SPUN researchers last year showing that 95% of the biodiversity hotspots for arbuscular mycorrhizal fungi are located outside protected areas.
For evolutionary biologist Dr. Toby Kiers, Executive Director of SPUN, this growing body of research is critical in developing more precise climate policies. “Fungi have been ignored in climate and conservation for too long. Now is the time to change that trajectory.” Kiers was recently named a prestigious MacArthur Fellow and winner of the Tyler Prize, known as the “Nobel Prize for the Environment,” for her work on plant-fungal systems.
“Mycorrhizal fungi have shaped life on earth for hundreds of millions of years, but we still understand too little about how the infrastructure of these living transport systems is distributed across the planet,” added co-author and biologist Dr. Merlin Sheldrake. “This study is an exciting step towards understanding how this planetary circulatory system operates and suggests ways that we can better work with fungi to help address many of the unfolding challenges of our times, from food security to climate change.”
This study helps quantify the extraordinary extent of AM fungal networks, but it also reveals how much remains unknown by pinpointing many regions of the planet which remain unsampled.
***
Society for the Protection of Underground Networks (SPUN): SPUN was founded in 2021 as a non-profit scientific research organization with a mission to map and protect Earth’s mycorrhizal networks. In collaboration with researchers and local communities, SPUN is accelerating efforts to protect the underground ecosystems largely absent from conservation and climate agendas. To learn more about SPUN, visit: https://spun.earth/.
Media contact: Magda Czyz magda@spun.earth Society for the Protection of Underground Networks (SPUN)
All Authors: Justin D. Stewart, Corentin Bisot, Rachael I.M. Cargill, Michael E. Van Nuland, Heidi Jayne Hawkins, Loreto Oyarte Galvez, Malin Klein, Marije van Son, Victoria Terry, Louis Paré, Claudia Banchini, Franck Stefani, Felix Kahane, Kai-Kai Lin, Renato K. Braghiere, Katie J. Field, Nadejda A. Soudzilovskaia, Jinsu Elhance, Vasilis Kokkoris, Merlin Sheldrake, James T. Weedon, Thomas S. Shimizu, Stuart West, E. Toby Kiers
Network architecture of fungal mycelium. Mycelial architecture varies across strains and species. Networks imaged at the AMOLF biophysics institute in Amsterdam.
Credit
Corentin Bisot - VU Amsterdam, AMOLF Justin Stewart - SPUN
Mycorrizhal fungi under the microscope at AMOLF biophysics institute in Amsterdam. The circular structures are spores. Color is altered for legibility.
Credit
Tomás Munita
Close up of soil core extraction.
Credit
Tomás Munita
Fungal networks imaged using a microscope at AMOLF biophysics institute in Amsterdam. Threads are arbuscular mycorrhizal hyphae.
A recent study by Ruibao Li and Jennah Dharamshi published in Naturemay help us understand the beginnings of animal evolution billions of years ago. These findings are the result of a collaboration between researchers at Indiana University Bloomington, the Institute of Evolutionary Biology in Spain and Uppsala University in Sweden, and was led by J. P. Gerdt and Iñaki Ruiz-Trillo.
These researchers found that after feeding a specific bacteria to a certain unicellular relative of animals, the single cells began to stick to one another, revealing a possible mode by which our ancestors began to evolve into animals billions of years ago.
Animal bodies are made up of trillions of cells that stick together and cooperate. Billions of years ago — before animals evolved — every living thing on earth was a single-celled organism. Eventually some of these cells began sticking together, working together and then reproducing as multicellular organisms. Some of these early multicellular organisms evolved into present-day plants or fungi, while others evolved into animals.
How the cells began to stick together and why they did so has long been a mystery to scientists. To get to the bottom of this enigma, Li and his colleagues studied Ministeria vibrans, a unicellular organism that shares ancient ancestors with present-day animals.
M. vibrans survives by eating bacteria. Li rigorously tested different bacterial foods until he found one that encouraged single M. vibrans cells to stick together and become multicellular. The bacteria got trapped between the aggregating cells, meaning that it was more efficient for M. vibrans to collect food by sticking together rather than remaining as single-celled organisms. Further, by sticking together, the cells might be able to protect their food from other organisms.
Sticking together also provides opportunities for cells to exchange genes via mating, which may produce new genetic combinations that enable adaptation to new environments.
Li and Dharamshi observed that when M. vibrans evolved from unicellular to multicellular, it produced the same proteins that many animal cells use to stick together. The multicellular form of M. vibrans also produced many proteins that animal cells use to communicate and coordinate behavior. The team concluded that the unicellular organisms that evolved into animals also likely used these proteins to form multicellular bodies and cooperate.
Li and his colleagues are excited to uncover further insights from the aggregation behavior of M. vibrans. Because the organism is much simpler than humans, it is easier to study, meaning it could even help reveal overlooked genes involved in certain developmental processes or diseases.
However, “What this organism is most powered to answer is what the unicellular ancestor of animals was like,” said J. P. Gerdt, associate professor of chemistry at Indiana University Bloomington. “It’s one of the best systems we have to go back a billion years to see what our ancestors were like at that stage.”
Nickel oxides serve as a catalyst precursor and accelerate the reduction kinetics by a factor of two, compared to an uncatalyzed hydrogen-based reduction. This is possible as nickel oxides bind with neighbouring iron oxides, creating an interface. Nickel breaks the incoming hydrogen molecules into highly reactive hydrogen atoms. These atoms then move across neighbouring iron oxide surfaces, a process known as hydrogen spillover, enabling accelerated reduction reactions.
Credit: Image taken from Nature Synthesis. DOI: 10.1038/s44160-026-01086-5.
Steel and metal production are among the largest contributors to global greenhouse gas emissions, accounting for approximately 10% of global CO2 emissions. At the same time, modern technology fully relies on having tailored steels and metals for applications in fields such as mobility, energy, infrastructure, safety and medicine. Hydrogen-based metal production offers a promising and CO2-free alternative and goes even further by integrating reduction, alloying and microstructure design into a single production step. However, hydrogen-based metal production still faces a number of challenges on its path to widespread adoption, one of which is the relatively slow reduction kinetics of metal ores at temperatures below 800°C.
A researcher team of the Max Planck Institute for Sustainable Materials (MPI-SusMat) has now made a significant breakthrough. They discovered that adding specific metal oxides as catalytic precursors can double the reduction kinetics of hydrogen-based metal production compared to uncatalyzed processes and allow a reduced energy use. The researchers have published their findings in the scientific journal Nature Synthesis.
Nickel oxides: the most promising catalyst for stainless and maraging steels
Conventional alloy production is typically a three-step process: first, reducing ores to metals, then mixing liquified elements to create an alloy, and finally applying thermomechanical treatments to achieve the desired properties. Each of these steps is energy-intensive and relies on carbon as both an energy carrier and a reducing agent, resulting in significant CO2 emissions and a high energy consumption. The MPI-SusMat team showed before, that a hydrogen-based reduction process allows to merge these three process steps into one single step.
Xinren Chen, postdoctoral researcher at MPI-SusMat and first author of the latest publication and his colleagues now show that this approach not only reduces carbon emissions by using hydrogen as the reducing agent, but can also fundamentally accelerate the reaction kinetics.
The team demonstrates how this one-step metallurgical process can be enhanced by adding nickel oxide during the hydrogen-based reduction of iron ores to iron-nickel alloys. The additional nickel oxides are co-reduced and form nanoporous nickel as a transient phase. This nanoporous nickel acts as a highly active catalyst precursor for the reduction of iron oxides and enhances their reduction rate.
“Adding nickel oxides to an ongoing reduction process of iron oxides, makes the overall reduction twice as fast. Atom probe tomography combined with transmission electron microscopy revealed that as the nickel oxides are rapidly reduced to porous metallic nickel, they bind with neighbouring iron oxides and create an interface. When hydrogen as the reducing agent hits this interface, the nickel helps split the hydrogen molecules into highly reactive hydrogen atoms. These atoms then move across neighbouring iron oxide surfaces, a process known as hydrogen spillover, enabling accelerated reduction reactions. Notably, the reduction can initiate at temperatures as low as 300°C, well below the ignition point of hydrogen”, explains Chen.
The resulting nickel-containing alloy is an important master alloy widely used in industrial steels, including stainless steels grades 304 and 316, as well as high-strength and cryogenic steels used for automotive, energy and medical applications.
Do other metal oxides have the same catalytic effect?
Using nickel oxides, the researchers successfully accelerated hydrogen-based iron ore reduction. Nickel is both thermodynamically and metallurgically compatible with iron, making it particularly effective in this process. “While other transition metal oxides have not yet been systematically evaluated, elements with similar properties, such as cobalt, are expected to exhibit comparable catalytic behaviour, offering promising directions for future investigation. In addition, oxides such as TiO2, although not readily reducible under these conditions, may also facilitate hydrogen spillover by providing active surface pathways for atomic hydrogen migration”, says Professor Dierk Raabe, managing director of MPI-SusMat and corresponding author of the publication.
Taken together, these results demonstrate that alloy formation and reduction can proceed simultaneously, rather than through the conventional sequence of post-reduction interdiffusion. This coupling of processes enhanced by metal oxide catalysts enables lower reduction temperatures, shorter processing times, and reduced energy consumption, opening up a more sustainable one-step route for producing iron-nickel master alloys. Beyond this specific system, the findings offer new mechanistic insights that could help drive a significant advance towards more energy-efficient and accelerated metallurgical extraction processes.
At MPI-SusMat, sustainable metal and alloy production is being explored from multiple perspectives, combining experimental and theoretical approaches. In solid-state direct reduction, the kinetics are governed by a complex interplay of factors including temperature, the choice of reductant and metal system, and catalytic effects. A deeper understanding of these coupled mechanisms is essential for guiding the development of next-generation, more sustainable and cost-efficient reduction technologies.
