In honor of National Fossil Day, we're highlighting this mouse deer fossil found in the Abocador de Can Mata, a garbage dump in Spain that has been the source of more than 70,000 fossils from the Miocene era—about 11.2 million to 12.5 million years ago—over the last two decades.

Researchers at Science Tokyo have identified two separate stem cell lineages responsible for forming tooth roots and the alveolar bone that anchors teeth in the jaw.

By using genetically modified mice and lineage-tracing methods, the team uncovered how specific signaling pathways direct stem cells to specialize during tooth development. Their findings provide valuable insight that could help advance the field of regenerative dentistry in the future.

The challenge of true tooth regeneration
The ability to regrow lost teeth and their surrounding bone structures remains one of the most sought-after goals in dental science. For many years, tooth replacement has relied on artificial substitutes such as dental implants and dentures. Although these solutions can effectively restore function and appearance, they cannot fully replicate the natural feel, biological integration, or structural complexity of real teeth.

This limitation has motivated researchers to explore how natural tooth formation occurs, in hopes of developing regenerative treatments that could restore lost teeth more completely.

However, tooth and bone formation is an extraordinarily complex process. It depends on the coordinated activity of multiple tissues, including the enamel organ, dental pulp, and jawbone cells. These components must communicate through finely tuned signaling networks to control the formation of the tooth crown, root, and the alveolar bone that supports the tooth. Despite decades of study, many aspects of these interactions remain poorly understood.

How does your brain recognize when it’s time to take a breath, when your blood pressure has fallen, or when your body is fighting an infection? The key lies in interoception, a little-known process through which the nervous system constantly monitors and interprets internal signals to keep essential body functions stable.

Researchers from Scripps Research and the Allen Institute have been awarded the National Institutes of Health (NIH) Director’s Transformative Research Award to develop the first comprehensive map, or atlas, of this internal sensory network.

The project will be led by Nobel Prize–winning neuroscientist Ardem Patapoutian, in collaboration with Li Ye, the N. Paul Whittier Chair in Chemistry and Chemical Biology at Scripps Research, and Bosiljka Tasic, Director of Molecular Genetics at the Allen Institute. Xin Jin, Associate Professor at Scripps Research, will serve as co-investigator and head the genomic and cell-type identification portion of the project. The initiative is supported by $14.2 million in NIH funding over the next five years.

“My team is honored that the NIH is supporting the kind of collaborative science needed to study such a complex system,” says Patapoutian, the Presidential Endowed Chair in Neurobiology at Scripps Research.

Decoding the Signals Within
Patapoutian, who shared the 2021 Nobel Prize in Physiology or Medicine for discovering cellular sensors of touch, will use the NIH award with his team to decode interoception.

“We hope our results will help other scientists ask new questions about how internal organs and the nervous system stay in sync,” adds Ye. Like Patapoutian, he’s also a Howard Hughes Medical Institute Investigator.

NASA astronaut Don Pettit has helped YouTuber Steve Mould with the final step in his "weird chain theory": testing the idea in space.

In 2013, YouTuber and science communicator Steve Mould brought the "chain fountain", an unsolved problem in physics, to the attention of the wider public. The effect, sometimes referred to as the "Mould effect" for his work on it, is strange to see. Simply put, place a long chain in a container, pull one end out, and let it fall to the floor. Now watch as the whole chain seems to jump up out of the glass, before falling towards the floor: Watch video

The effect, though independently found by Mould, was known about before, even if it was unexplained. Since the effect was popularized by Mould, he, Mehdi Sadaghdar of YouTube channel ElectroBOOM, and several academic studies have attempted to explain it. Mould has also set the record for the biggest chain fountain.

SpaceX closed out a dramatic chapter in the development of its super-heavy-lift Starship launch system with a successful flight test that mostly followed the noscript for the previous flight test.

The 11th test flight began with the ascent of Starship’s Super Heavy booster from SpaceX’s Starbase launch pad in South Texas at 6:23 p.m. CT Oct. 13 (11:23 p.m. UTC). It was that particular pad’s last liftoff. An upgraded Pad 2 is being prepared to accommodate a more powerful Starship Version 3, with the first launch expected next year.

Starship V3 will feature an upgraded version of SpaceX’s methane-fueled Raptor engines and larger propellant tanks that are capable of in-orbit refueling.

The Super Heavy booster and its second stage, known as Ship, are being designed for missions in Earth orbit and beyond — and V3 is the version that’s meant to get SpaceX to that level.

NASA is counting on SpaceX to provide a modified version of Starship for landing astronauts on the moon by as early as 2027. SpaceX founder Elon Musk is counting on Starship to carry robots and humans to the moon and Mars, in accordance with his vision of making humanity a multiplanet species.

Standing a little more than 400 feet tall (122 metres), Starship is considered the world’s most powerful rocket, with liftoff thrust of 16.7 million pounds (7.5 million kg). That’s more than twice the oomph achieved by the Saturn V rocket during the Apollo era’s heyday.
Watch launch video

A strange new phase of ice has been discovered during experiments with the world's largest X-ray laser. Meet ice XXI, a bizarre phase that forms at room temperature, under extreme pressure.

The solidified water we're most familiar with here on Earth is technically known as ice I, but it's just the tip of the iceberg – for instance, aliens on Neptune could be dropping ice XVIII in their drinks. Exposing plain old H2O to different temperature and pressure conditions could result in more than 20 different phases of the stuff, in fact.

Ice XXI is the latest to join the ranks. It has a tetragonal crystal structure with fairly large repeating units consisting of 152 water molecules, which makes it distinct from all other known phases of ice.

Don't expect to whip up a few fancy cubes of ice XXI in your freezer at home, though. Or any kind of freezer for that matter.

The researchers used a diamond anvil cell at the European XFEL facility in Germany to squeeze water to pressures of up to 2 gigapascals (about 20,000 times the air pressure at sea level) within 10 milliseconds.

They then released the pressure relatively slowly – over a leisurely period of one second – before repeating the process. The whole time, the X-rays captured a million images per second to see how the crystal structure changes.

Human embryo models capable of synthesizing their own blood have been developed, in an advance that could lead to new treatments for blood disorders as well as the production of stem cells for transplants.

The 3D structures, named “hematoids”, are similar to embryos but differ in several important ways. They don’t have the capacity to continue to develop into a fetus – they lack essential tissues and would also require a yolk sac and placenta. However, what the study demonstrates is that they can effectively simulate processes that happen during the early stages of embryo growth.

The hematoids self-assemble from human pluripotent stem cells, which can be nudged down any development pathway to become any type of human tissue. On only the second day of development, the team observed that the hematoids had arranged themselves into the three layers that lay the foundation for the human body plan: the ectoderm, mesoderm, and endoderm.

On the eighth day, some of the hematoid cells were beating – the precursors to a heart.

And after around two weeks of development in the lab, the scientists observed the first tell-tale signs that they’d begun producing blood.

“It was an exciting moment when the blood red colour appeared in the dish – it was visible even to the naked eye,” said co-first author Dr Jitesh Neupane, of the University of Cambridge’s Gurdon Institute, in a statement.

In normal embryogenesis, this stage corresponds to around four or five weeks of development. It’s not possible to observe this directly in a living human because the embryo would have implanted into the uterus wall by then, so these models are our only chance to study these processes in detail.

“Our new model mimics human foetal blood development in the lab. This sheds light on how blood cells naturally form during human embryogenesis, offering potential medical advances to screen drugs, study early blood and immune development, and model blood disorders like leukaemia,” said Neupane.

Co-first author Dr Geraldine Jowett added, “Hematoids capture the second wave of blood development that can give rise to specialised immune cells or adaptive lymphoid cells, like T cells, opening up exciting avenues for their use in modelling healthy and cancerous blood development.”

Academics at the University of Oxford and the University of Pennsylvania have conducted the most comprehensive review of evidence on the effectiveness on carbon offsetting to date and concluded the practice is ineffective and riddled with "intractable" problems. The review is published in the Annual Review of Environment and Resources.

Carbon offsets are projects that generate credits meant to represent the reduction, avoidance, or removal of greenhouse gas (GHG) emissions from the atmosphere. The first carbon offset was generated in 1989. The authors call for the phasing out of most credits except those generated by permanent carbon dioxide removal.

"We must stop expecting carbon offsetting to work at scale. We have assessed 25 years of evidence and almost everything up until this point has failed," says co-author Dr. Stephen Lezak, researcher at the Smith School of Enterprise and the Environment. "The present market failures are not due to a few bad apples but rather to systematic, deep-seated problems, which will not be resolved by incremental changes."

"We hope our findings provide a moment of clarity ahead of COP30: These junk offsets—the ones not backed by permanent carbon removal and storage—are a dangerous distraction from the real solution to climate change, which is rapid and sustained emission reductions," says lead author Dr. Joseph Romm, Senior Research Fellow at the Penn Center for Science, Sustainability and the Media.

The most severe issues uncovered by the research are nonadditionality (generating credits without reducing emissions), impermanence, leakage, double counting, "perverse incentives," and the "gameability" of crediting systems, where bad actors have been able to routinely circumvent even well-designed rules. Far from solving these problems, Article 6 of the Paris Agreement, which was finalized at COP29, simply restated "long-ignored tenets of carbon market development, with the specious expectation that this time the outcomes might differ significantly," the authors say.

"Despite efforts to implement safeguards, carbon offset projects continue to face documented cases of weak accountability, risking the perpetuation of neocolonial patterns of appropriation. While nature-based projects can deliver local benefits, these should be financed through mechanisms other than carbon credits, such as contribution claims where projects are financed while still ensuring that purchasing entities are responsible for reducing their own emissions," says co-author Amna Alshamsi, a doctoral researcher at the University of Sussex's School of Global Studies.

Previous research has shown how offset programs routinely overestimate their climate impact, in many cases by as much as a factor of 10 or more.

A weak spot in Earth's magnetic field over the South Atlantic Ocean has ballooned in size since 2014, satellite data reveals.

The region, known as the South Atlantic Anomaly, has grown by an area nearly half the size of continental Europe, sprouting a lobe in the direction of Africa where the field is weakening the fastest.

And the anomaly, linked to mysterious fluctuations near Earth's outer core, could pose a risk to satellites passing over the region, according to a study published in the November issue of the journal Physics of the Earth and Planetary Interiors.

"The South Atlantic Anomaly is not just a single block," study lead author Chris Finlay, a professor of geomagnetism at the Technical University of Denmark, said in a statement. "It's changing differently towards Africa than it is near South America. There's something special happening in this region that is causing the field to weaken in a more intense way."

Researchers first detected the South Atlantic Anomaly in the 19th century. Inside its boundaries, the magnetic field that radiates away from Earth's interior dips down to an altitude of about 120 miles (200 kilometers) above the planet's surface, which is much lower than the field's average altitude of about 400 miles (650 km).

This poses a threat to satellites and other spacecraft. Earth's magnetic field shields the planet and objects in low Earth orbit from charged solar particles and incoming X-ray and ultraviolet radiation, so spacecraft traveling over the South Atlantic Anomaly are exposed to more of these impacts. This could lead to malfunctions or damage in hardware, and even blackouts, according to the statement.

Finlay and his colleagues think the South Atlantic Anomaly is growing and spreading eastward due to strange fluxes at the limit between Earth's mantle and outer core, the layers of the planet sandwiched between Earth's crust and inner core.

Modularity is taking off in more ways than one in space exploration. The design of the upcoming “Lunar Gateway” space station is supposed to be modular, with different modules being supplied by different organizations. In an effort to extend that thinking down to rovers on the ground, a new paper from researchers at Germany’s space agency (DLR), developed an architecture where a single, modular rover could be responsible for both exploration and carrying payloads around the Moon or Mars.

The architecture itself is simple enough - use a rover to pull around specialized “payloads”, all of which use a standardized mechanical connection that allows electricity and fluids to flow between the rover and the payload. That connection also allows the rover to pull the payload to where it is needed and connect it to other infrastructure in the area. The payloads could vary depending on the need. They could be a power supply, a suite of scientific instruments, or even construction attachments like a shovel or backhoe.

A typical use case for this type of infrastructure is exemplified by water extraction on the Moon. The rovers, which are derived from the TransRoPorter (TRP) concept originally developed at DLR, would be responsible for scouting where potential water ice might exist. They could then bring the necessary equipment, in the form of payloads, to any ice they discover. They could also then be used to move the water ice from the mining site to locations where it could be better utilized, such as rocket fuel factories of astronaut habitats.

Uranus and Neptune are the two furthest planets in the Solar System and have been visited only once by human spacecraft – by Voyager 2 over 30 years ago – so there is a lot about them that we do not know. One thing we thought we knew, however, was what type of planet they are. Now, a new study wants to challenge something quite crucial about how we classify them: these worlds, it argues, are not ice giants.

The four "rocky" planets of the Solar System – Earth, Mars, Venus, and Mercury – are small terrestrial planets made of solid rock and metal. The four giant planets – Jupiter, Saturn, Uranus, and Neptune – are divided into two categories because, though large, they are not the same. The first two are "gas giants" because they are overwhelmingly composed of hydrogen and helium, over 90 percent by mass. The latter two are known as "ice giants". Hydrogen and helium comprise less than 20 percent of the planets' masses. Uranus and Neptune, instead, are rich in numerous molecules like water and ammonia that were present in solid ice when the planets formed billions of years ago, as models tell us.

For decades, our understanding of Uranus and Neptune's interiors has been based on what we can glean from their surface features, the behaviors of their moons, their magnetic fields, and other indirect means. Which has occasionally led us astray. 

If I was one of these billionaires… just floating around with all my money, I would fund two missions: I'd fund an orbiter to Uranus and an orbiter to Neptune.
— Prof Brian Cox

This new work suggests a different way of looking at these outer planets. Instead of modeling the interior of these two worlds based on the potentially flawed information we have, they created random models and then compared those to observational data, building a catalog of models that fit. They looked at both water-dominated and rock-dominated scenarios and concluded that while the planets have this mixture of molecules, a rockier internal structure makes more sense with the current observations. 

“Overall, our findings challenge the conventional classification of Uranus and Neptune as ’ice giants’ and underscore the need for improved observational data or formation constraints to break compositional degeneracy,” the authors write in their paper.

The cavendish experiment shows that even the very week force of gravity can be seen between two room scale objects. Even with the naked eye.

The effects of a COVID-19 infection can sometimes persist for months or years after the initial symptoms have gone, but could some of the impact even be transferred to the next generation? Scientists studying male mice infected with SARS-CoV-2 discovered that it could alter their sperm, leading to behavioral changes in their offspring. It remains to be seen whether the same is true in humans.

“We already knew that when male mice were exposed to specific environmental and lifestyle factors, like poor diet before mating, it could change brain development and behaviour in offspring,” said lead researcher Professor Anthony Hannan from The Florey Institute of Neuroscience and Mental Health in a statement.

“This is because the father’s experiences can alter the information carried in sperm, including specific RNA molecules, which transmit instructions for offspring development.”

Research had already shown how COVID-19 – which we know has effects way beyond the respiratory system – can alter sperm, potentially hanging around for up to 110 days. The team wanted to investigate whether COVID also had the potential to cause this type of RNA damage.

Green auroras stretching as far as the eye can see, almost mistakable for another planet rather than the blue Earth we call home.

New research has shown, for the first time, how mixtures of commonly used medications that end up in our waterways and natural environments might increase the development of antibiotic-resistant bacteria.

When humans or animals take medications, as much as 90% can pass through the body and into natural environments, via waste water, or run-off from fields, ending up in the ocean.

In the environment, this build-up of antibiotic medicines can accumulate to a strength sufficient to kill the bacteria that live there. This can result in bacteria evolving defenses that help them to survive these concentrations, which can mean they are also resistant to antibiotics used to treat them if they later infect humans.

However, less is known about how the build-up of other medicines also affects bacteria, and until now, scientists have largely investigated the effect of these medications on triggering this antibiotic resistance one-at-a-time.

Now, new research led by the University of Exeter and published in the journal ISME Communications, has revealed that regular drugs used for pain relief, diabetes medication, and hormone replacement can increase the tendency for bacteria to develop the genes needed to resist antibiotic treatments, when combined with a common antibiotic as happens in the environment.

How do you spot pregnant individuals in the archaeological record? With great difficulty, it turns out. But that could be about to change, as a test capable of identifying hormones in skeletons breaks new ground in our understanding of ancient pregnancy.

For the first time, estrogen, progesterone, and testosterone have been detected in multiple human hard tissues, which could serve as an indicator of pregnancy, explain the authors of a recent study presenting the findings.

Nowadays, pregnancy tests work by identifying the hormone human chorionic gonadotrophin (hCG) in urine – at one time, this involved frogs, believe it or not. However, hCG doesn’t linger in the body for long enough to be detectable in ancient remains. This means that archaeologists have, until now, had to rely on discovering fetal remains in the abdomens of pregnant people, which is incredibly difficult, nigh on impossible, to do.

“New methods that can accurately identify pregnancy from skeletal remains are needed if we are to accurately reconstruct past women's reproductive histories, interpret their experiences within social and cultural contexts, and make effective comparisons between modern and archaeological populations,” the team behind the latest breakthrough explains.

The Sahara Desert is one of the driest areas in the world. It gets just 3 inches of precipitation per year—one-tenth of the amount of Chicago's rain, sleet and snow.

But by the second half of the 21st century, rising global temperatures could make the Sahara much wetter, according to UIC researchers. By that time, the North African desert could see 75% more precipitation than its historical norm, as reported in npj Climate and Atmospheric Science. Under extreme climate conditions, rainfall is expected to increase in southeastern and south-central Africa, too, the researchers said.

"Changing rainfall patterns will affect billions of people, both in and outside Africa," said lead author Thierry Ndetatsin Taguela, a postdoctoral climate researcher in the College of Liberal Arts and Sciences. "We have to start planning to face these changes, from flood management to drought-resistant crops."

For thousands of years, people in the Andes have chewed the leaves of the coca plant to stave off hunger, treat altitude sickness, and sustain energy. Yet under international law, this ancient crop is treated as harshly as cocaine and fentanyl. Now, scientists say it's time to end that contradiction.

A new international perspective published in Science argues that scientific evidence clearly supports the coca leaf as a benign, useful, and culturally paramount crop plant that should be removed from the list of Schedule I substances—where it currently appears alongside cocaine and fentanyl—under the 1961 "Single Convention on Narcotic Drugs."

"Coca's record of safe use and cultural importance stands in stark contrast to the harms of purified cocaine," said lead author Dawson M. White, Postdoctoral Researcher in the Department of Organismic and Evolutionary Biology at Harvard.

"Recognizing this difference is essential for evidence-based policy and for aligning with the goals expressed by South American communities most affected by prohibition."

The analysis arrives at a pivotal moment, as the World Health Organization (WHO) is currently reviewing the legal status of coca. An expert report compiled by the WHO confirms both the lack of harm from the coca leaf and the tangible harms caused by its prohibition. The WHO's Expert Committee on Drug Dependence (ECDD) will meet in Geneva from October 20–22, 2025, to formalize a recommendation to the United Nations (UN) Commission on Narcotic Drugs.

The Biodiversity Collections Network (BCoN), in collaboration with the American Institute of Biological Sciences (AIBS), has developed a comprehensive roadmap toward an integrated biological and environmental data network.

The initiative, known as the Building an Integrated, Open, Findable, Accessible, Interoperable, and Reusable (BIOFAIR) Data Network project, addresses the urgent need to connect fragmented data held in biodiversity collections and other biological and environmental data repositories to tackle pressing societal challenges, including biodiversity loss, climate change, invasive species, and emerging public health threats.

The project, described in a recent article in the journal BioScience, was underpinned by extensive community engagement with ecological, climate, environmental, genetic, health, biodiversity informatics, and federal stakeholders.

Through six virtual listening sessions, project organizers engaged 199 stakeholders representing 142 organizations, followed by a workshop with 75 participants affiliated with 110 organizations and initiatives. The collaborative effort developed five cross-cutting themes to guide data integration: stock-taking and gap analysis, technological capacity building, best practices and standards, education and training, and community building.

"Biodiversity collections, including over a billion specimens in the United States, offer unparalleled information for understanding evolution, biological processes, and biodiversity responses to environmental change," the authors explain.

Scientists have identified a unique population of brain cells responsible for forming memories of meals, capturing both what was eaten and when it occurred. The research, published in Nature Communications, may help explain why individuals with memory difficulties are more prone to overeating and why forgetting a recent meal can heighten hunger and contribute to unhealthy eating behaviors.

As eating takes place, neurons in a part of the brain called the ventral hippocampus become active, creating what the researchers describe as “meal engrams.” These are specialized memory traces that record details of eating experiences. Although engrams have long been known to store general memories and experiences, this study is the first to reveal a set of engrams specifically linked to meals.

“An engram is the physical trace that a memory leaves behind in the brain,” said Scott Kanoski, professor of biological sciences at the USC Dornsife College of Letters, Arts and Sciences and corresponding author of the study. “Meal engrams function like sophisticated biological databases that store multiple types of information such as where you were eating, as well as the time that you ate.”

Distracted eating implications
The discovery has immediate relevance for understanding human eating disorders. Patients with memory impairments, such as those with dementia or brain injuries that affect memory formation, may often consume multiple meals in quick succession because they cannot remember eating.

Furthermore, distracted eating — such as mindlessly snacking while watching television or scrolling on a phone — may impair meal memories and contribute to overconsumption.

Based on the experiment’s findings, meal engrams are formed during brief pauses between bites when the brain of laboratory rats naturally survey the eating environment. These moments of awareness allow specialized hippocampal neurons to integrate multiple streams of information.

The amount of REM sleep you get may influence which details of your memories remain in storage, a new brain study suggests.

Previous research had found that sleep helps fortify our memories, but the question of how it shapes the contents of these memories has been harder to pin down. Now, a study published Oct. 1 in the journal Communications Biology hints that the time spent in different stages of sleep may influence this aspect of memory storage.

The sleep cycle is split into four stages: one stage of rapid eye movement (REM) and three non-REM stages, including "deep sleep," marked by slow brain waves. To test how these sleep stages impact our memories, the researchers asked 32 healthy young adults to learn 96 word-picture pairs — such as an action word linked to an image of an animal or plant — while their brain activity was recorded with an electroencephalogram (EEG), which monitors brain waves that wash over the surface of the brain.

The volunteers were then monitored with EEG as they slept overnight and had their recall tested the next morning. The researchers compared the before-and-after brain patterns using a technique called representational similarity analysis. These data enabled the scientists to focus both on detailed memories tied to specific images — like a photo of a beagle — and on broader, categorical memories, covering all the animal images, for instance.

"By using EEG, we could track how brain activity linked to memories changed from before to after sleep," first study author Jing Liu, a research assistant professor at The Hong Kong Polytechnic University, told Live Science in an email.

The team uncovered a pattern: Brainwaves linked to the individual images weakened after sleep, while the broader category signals remained stable.

The shift was stronger when REM made up more of an individual's total sleep time, compared to deep sleep. Liu explained that this pattern suggests REM sleep may help the brain link new memories with what it already knows, while slow-wave sleep helps keep those memories in their original, more-detailed form.