A 500-million-year-old fossil from Morocco, discovered by Natural History Museum scientists, is offering extraordinary new insights into one of evolution’s most puzzling transformations: how echinoderms, the group that includes starfish, sea cucumbers and sea urchins, evolved from ancestors that showed bilateral symmetry, like humans, to the unique fivefold symmetry we see today.
The fossil, Atlascystis acantha, is the oldest known echinoderm with a bilateral body plan. It bridges the evolutionary gap between the closest living relatives of echinoderms, all of which have bilateral symmetry, and the familiar pentaradial (five-armed) forms alive today.
“This fossil evidence allows us to piece together how the body plans of starfish and their relatives evolved step-by-step from ancestors that were much more similar in shape to other animals,” said Dr. Imran Rahman, Principal Researcher at the Museum and co-lead author of the study.
Unearthed in the Anti-Atlas mountains of Morocco, Atlascystis has a flattened, spine-covered body with bilateral symmetry and a pair of specialized sets of skeletal plates similar to those used by living echinoderms to move and feed, known as ambulacra. These features are characteristic of modern echinoderms, yet until now their presence in early bilaterally symmetrical forms was unclear.
Atlascystis acantha from the Cambrian stage 4–Wuliuan boundary interval of Morocco. Credit: Current Biology (2025). DOI: 10.1016/j.cub.2025.05.065
Rewriting evolutionary history
Using 3D imaging, growth analyses and cutting-edge phylogenetic methods, the research team reconstructed the evolutionary trajectory of echinoderms. The study challenges previous suggestions that early bilateral echinoderms were simply offshoots of more derived forms. Instead, the researchers show these organisms lie at the base of the echinoderm evolutionary tree, and that five-rayed forms likely evolved later through the duplication of a single ambulacrum, enabled by the loss of a defined trunk region.
Dr. Frances Dunn, senior researcher at the Oxford University of Natural History, said, “The fossil record remains our only direct insight into the evolutionary history of groups through time, and this discovery shines a light on the first steps of the evolution of one of the most recognizable body plans we find in animals today: the starfish.”
Dr. Jeff Thompson, lecturer at the University of Southampton and co-author on the paper, said, “We were able to determine how this animal grew when it was alive, which was the key to understanding its place in the tree of life.”
The discovery reinforces the importance of the fossil record in solving evolutionary mysteries that genetics alone cannot untangle. With Atlascystis acantha, scientists now have a powerful new window into how major animal groups like echinoderms assembled their body plans in deep time.
The paper “A new Cambrian stem-group echinoderm reveals the evolution of the anteroposterior axis” is available now in Current Biology.
More information: Stephanie C. Woodgate et al, A new Cambrian stem-group echinoderm reveals the evolution of the anteroposterior axis, Current Biology (2025). DOI: 10.1016/j.cub.2025.05.065
The Mediterranean Sea on Sunday hit its warmest temperature on record for June at 26.01 degrees Celsius, said a French weather service scientist, citing data from EU monitor Copernicus.
“We have never measured such a high daily temperature in June, averaged over the basin, as Sunday,” said Thibault Guinaldo, a researcher at the Center for Satellite Meteorology Studies under Meteo-France.
At present, sea surface temperatures in the Mediterranean are 3C higher than average for the same period compared to 1991-2020, with spikes exceeding 4C around the French and Spanish coasts, he added.
“Given the week we’re going to have in terms of weather conditions, unfortunately it’s not going to get any cooler,” Guinaldo said.
It comes as Europe swelters through summer’s first major heat wave, with Spain and Portugal setting new temperature highs on Monday as France, Italy and Britain also sizzled.
The oceans are a vital regulator of Earth’s climate, absorbing some 90% of the excess heat in the atmosphere caused by humanity’s burning of fossil fuels.
The Mediterranean region is warming faster than the global average and scientists say that climate change is making marine heat waves more frequent and powerful.
Since 2023, there have been consistent waves of abnormally high temperatures. The Mediterranean hit a new all-time high temperature of 28.47C in August 2024, blitzing the previous record set in July 2023.
The basin is also cooling much more slowly during the winter months: every year since 2023 has experienced well above average temperatures between October and April, said Guinaldo.
This has prolonged extreme conditions year round that harm sea life, reduce fish stocks and whip-up stronger storms that make landfall with devastating consequences.
A 2022 study found that marine heat waves in the Mediterranean between 2015 and 2019 caused widespread death in around fifty underwater species including corals, sea urchins and mollusks.
When the island of Santorini was rattled by thousands of small earthquakes earlier this year, many people were left mystified about the source of the tremors.
The shaking lasted more than a month and forced more than 10,000 people to evacuate the Greek island. At times, the earthquakes occurred every few minutes. The largest reached a 5.3 magnitude.
But University of Oregon geophysicist Emilie Hooft felt less perplexed about the source of the earthquakes, as she had an informed hunch about what was going on.
Just 10 days before the earth started quaking in the Greek islands, Hooft’s lab submitted a paper outlining new discoveries about the volcanic plumbing surrounding Santorini, which offered some important clues about the source of the earthquakes. While some scientists initially assumed they were connected to a tectonic event related to the fault system near Santorini, Hooft’s research suggested they were actually fueled by volcanic unrest deep in the crust.
Namely, the underground magma movement that was transpiring six to nine miles beneath the volcanic system—though, importantly, offset so they were not directly below the volcanoes themselves.
“We found magma at deeper depths that is offset from both the main volcano and from the active volcanic seamount 10 kilometers (6 miles) to the northeast,” Hooft said. “Two Ph.D. students worked with me to probe deeper beneath the volcanic system than any prior efforts and found magma that proved to be the source of a sideways injection of magma deep in the crust, located right where the seismic swarm was initiated.”
Hooft’s lab published two related papers earlier this year in the journal Geochemistry, Geophysics, Geosystems. Both projects grew out of extensive research into the crustal structure of the crust and the magmatic evolution of the Santorini volcanic complex.
In the first paper, doctoral student Beck Hufstetler’s research used sound waves to map out the melt content of the magma system. And in the second, doctoral student Kaisa Autumn used different sound waves to find deep magma deep under the volcanic region, which surprisingly aligned with the location of the seismic activity.
“Because the recent earthquakes weren’t in line with any known volcanic features, other scientists did not immediately recognize them as having a volcanic origin,” Hooft explained. “Our research showed that these earthquakes were not offset from all the known volcanic features; they’re actually sourced right from this deep magma storage region that we discovered.”
Hooft said scientists are increasingly finding evidence that magma is not always located directly under the major, and most visible, mountain of a volcano.
“Our research reinforces a growing view that volcanic unrest shouldn’t be considered in isolation, but as part of a complex, evolving system of magma, fault and crust,” she said. “Magma movement is often guided by structural features of the crust, like cracks in the fault system, which means future volcanic unrest may occur outside traditional volcanic centers.”
Hooft began studying the region in 2015, and led one of the largest seismic imaging projects conducted at a volcano. For nearly a month, the international team of researchers covered around-the-clock shifts to send powerful sound waves through the ocean to collect information about Santorini’s volcanic plumbing.
The sound waves, which are created through canisters of compressed air, function like an ultrasound that can detect what kind of material makes up the volcanic system, including lava, rock and water.
“We were able to probe far under the volcano to really understand the deepest part of the plumbing system of a subduction zone arc volcano,” she said, adding that the research both improved the resolution of the shallow and mid-crust layers, while also imaging deeper into the crust than any prior studies.
The crust is generally around 15 miles thick, and until these two projects, Hooft’s research had been limited to the first three to four miles of the crust.
Hooft’s group was especially interested in understanding how magma moves throughout the entire crust and how it interacts with the fault system beneath volcanoes like those around Santorini. To measure deeper into the more compact part of the crust, Autumn had to use a more advanced method, which involved using reflected sound waves to image the entire crust.
They found that magma was moving in the cracks created by the fault system six to nine miles beneath the surface. Because the cracks are offset from the volcanoes themselves, they’re creating potential pathways for magma to move sideways while remaining underground.
Hooft hopes to keep building on her work in Santorini so she can fill more gaps in the research.
“Understanding how and when magma moves through these systems remains one of the central challenges in volcanic science and a critical step toward detecting early warning signs and improving hazard assessment in vulnerable regions like the southern Aegean,” she said.
More information: R. S. Hufstetler et al, Seismic Structure of the Mid to Upper Crust at the Santorini‐Kolumbo Magma System From Joint Earthquake and Active Source Vp‐Vs Tomography, Geochemistry, Geophysics, Geosystems (2025). DOI: 10.1029/2024GC012022
Kaisa R. Autumn et al, Exploring Mid‐to‐Lower Crustal Magma Plumbing of Santorini and Kolumbo Volcanoes Using PmP Tomography, Geochemistry, Geophysics, Geosystems (2025). DOI: 10.1029/2025GC012170
The biggest environmental problems for commercial plantation forestry in New Zealand’s steep hill country are discharges of slash (woody debris left behind after logging) and sediment from clear-fell harvests.
During the past 15 years, there have been 15 convictions of forestry companies for slash and sediment discharges into rivers, on land and along the coastline.
Such discharges are meant to be controlled by the National Environmental Standards for Commercial Forestry, which set environmental rules for forestry activities such as logging roads and clear-fell harvesting. The standards are part of the Resource Management Act (RMA), which the government is reforming.
The government revised the standards’ slash-management rules in 2023 after Cyclone Gabrielle. But it is now consulting on a proposal to further amend the standards because of cost, uncertainty and compliance issues.
We believe the proposed changes fail to address the core reasons for slash and sediment discharges.
We recently analyzed five convictions of forestry companies under the RMA for illegal discharges. Based on this analysis, which has been accepted for publication in the New Zealand Journal of Forestry, we argue that the standards should set limits to the size and location of clear-felling areas on erosion-susceptible land.
Why the courts convicted five forestry companies
In the aftermath of destructive storms in the Gisborne district during June 2018, five forestry companies were convicted for breaches of the RMA for discharges of slash and sediment from their clear-fell harvesting operations. These discharges resulted from landslides and collapsed earthworks (including roads).
There has been a lot of criticism of forestry’s performance during these storms and subsequent events such as Cyclone Gabrielle. However, little attention has been given to why the courts decided to convict the forestry companies for breaches of the RMA.
The courts’ decisions clearly explain why the sediment and slash discharges happened, why the forestry companies were at fault, and what can be done to prevent these discharges in future on erosion-prone land.
New Zealand’s plantation forest land is ranked for its susceptibility to erosion using a four-color scale, from green (low) to red (very high). Because of the high erosion susceptibility, additional RMA permissions (consents) for earthworks and harvesting are required on red-ranked areas.
New Zealand-wide, only 7% of plantation forests are on red land. A further 17% are on orange (high susceptibility) land. But in the Gisborne district, 55% of commercial forests are on red land. This is why trying to manage erosion is such a problem in Gisborne’s forests.
This map shows areas with the highest and lowest susceptibility to erosion. Credit: David Palmer/Te Uru Rākau, CC BY-SA
Key findings from the forestry cases
In all five cases, the convicted companies had consents from the Gisborne District Council to build logging roads and clear-fell large areas covering hundreds or even thousands of hectares.
A significant part of the sediment and slash discharges originated from landslides that were primed to occur after the large-scale clear-fell harvests. But since the harvests were lawful, these landslides were not relevant to the decision to convict.
Instead, all convictions were for compliance failures where logging roads and log storage areas collapsed or slash was not properly disposed of, even though these only partly contributed to the collective sediment and slash discharges downstream.
The court concluded that:
Clear-fell harvesting on land highly susceptible to erosion required absolute compliance with resource consent conditions. Failures to correctly build roads or manage slash contributed to slash and sediment discharges downstream.
Even with absolute compliance, clear-felling on such land was still risky. This was because a significant portion of the discharges were due to the lawful activity of cutting down trees and removing them, leaving the land vulnerable to landslides and other erosion.
The second conclusion is critical. It means that even if forestry companies are fully compliant with the standards and consents, slash and sediment discharges can still happen after clear-felling. And if this happens, councils can require companies to clean up these discharges and prevent them from happening again.
This is not a hypothetical scenario. Recently, the Gisborne District Council successfully applied to the Environment Court for enforcement orders requiring clean-up of slash deposits and remediation of harvesting sites. If the forestry companies fail to comply, they can be held in contempt of court.
Regulations are not just red tape
This illustrates a major problem with the standards that applies to erosion-susceptible forest land everywhere in New Zealand, not just in the Gisborne district. Regulations are not just “red tape”. They provide certainty to businesses that as long as they are compliant, their activities should be free from legal prosecution and enforcement.
The courts’ decisions and council enforcement actions show that forestry companies can face considerable legal risk, even if compliant with regulatory requirements for earthworks and harvesting.
Clear-felled forests on erosion-prone land are one bad rainstorm away from disaster. But with well-planned, careful harvesting of small forest areas, this risk can be kept at a tolerable level.
However, the standards and the proposed amendments do not require small clear-fell areas on erosion-prone land. If this shortcoming is not fixed, communities and ecosystems will continue to bear the brunt of the discharges from large-scale clear-fell harvests.
To solve this problem, the standards must proactively limit the size and location of clear-felling areas on erosion-prone land. This will address the main cause of catastrophic slash and sediment discharges from forests, protecting communities and ecosystems. And it will enable forestry companies to plan their harvests with greater confidence that they will not be subject to legal action.
Hurricane Helene lasted only a few days in September 2024, but it altered the landscape of the Southeastern U.S. in profound ways that will affect the hazards local residents face far into the future.
Mudslides buried roads and reshaped river channels. Uprooted trees left soil on hillslopes exposed to the elements. Sediment that washed into rivers changed how water flows through the landscape, leaving some areas more prone to flooding and erosion.
Helene was a powerful reminder that natural hazards don’t disappear when the skies clear—they evolve.
These transformations are part of what scientists call cascading hazards. They occur when one natural event alters the landscape in ways that lead to future hazards. A landslide triggered by a storm might clog a river, leading to downstream flooding months or years later. A wildfire can alter the soil and vegetation, setting the stage for debris flows with the next rainstorm.
I study these disasters as a geomorphologist. In a new paper in the journal Science, I and a team of scientists from 18 universities and the U.S. Geological Survey explain why hazard models—used to help communities prepare for disasters—can’t just rely on the past. Instead, they need to be nimble enough to forecast how hazards evolve in real time.
The science behind cascading hazards
Cascading hazards aren’t random. They emerge from physical processes that operate continuously across the landscape—sediment movement, weathering, erosion. Together, the atmosphere, biosphere and Earth are constantly reshaping the conditions that cause natural disasters.
For instance, earthquakes fracture rock and shake loose soil. Even if landslides don’t occur during the quake itself, the ground may be weakened, leaving it primed for failure during later rainstorms.
That’s exactly what happened after the 2008 earthquake in Sichuan Province, China, which led to a surge in debris flows long after the initial seismic event.
Earth’s surface retains a “memory” of these events. Sediment disturbed in an earthquake, wildfire or severe storm will move downslope over years or even decades, reshaping the landscape as it goes.
The 1950 Assam earthquake in India is a striking example: It triggered thousands of landslides. The sediment from these landslides gradually moved through the river system, eventually causing flooding and changing river channels in Bangladesh some 20 years later.
An intensifying threat in a changing world
These risks present challenges for everything from emergency planning to home insurance. After repeated wildfire-mudslide combinations in California, some insurers pulled out of the state entirely, citing mounting risks and rising costs among the reasons.
Cascading hazards are not new, but their impact is intensifying.
Climate change is increasing the frequency and severity of wildfires, storms and extreme rainfall. At the same time, urban development continues to expand into steep, hazard-prone terrain, exposing more people and infrastructure to evolving risks.
The rising risk of interconnected climate disasters like these is overwhelming systems built for isolated events.
Yet climate change is only part of the equation. Earth processes—such as earthquakes and volcanic eruptions—also trigger cascading hazards, often with long-lasting effects.
Mount St. Helens is a powerful example: More than four decades after its eruption in 1980, the U.S. Army Corps of Engineers continues to manage ash and sediment from the eruption to keep it from filling river channels in ways that could increase the flood risk in downstream communities.
Rethinking risk and building resilience
Traditionally, insurance companies and disaster managers have estimated hazard risk by looking at past events.
But when the landscape has changed, the past may no longer be a reliable guide to the future. To address this, computer models based on the physics of how these events work are needed to help forecast hazard evolution in real time, much like weather models update with new atmospheric data.
Thanks to advances in Earth observation technology, such as satellite imagery, drone and lidar, which is similar to radar but uses light, scientists can now track how hillslopes, rivers and vegetation change after disasters. These observations can feed into geomorphic models that simulate how loosened sediment moves and where hazards are likely to emerge next.
Researchers are already coupling weather forecasts with post-wildfire debris flow models. Other models simulate how sediment pulses travel through river networks.
Cascading hazards reveal that Earth’s surface is not a passive backdrop, but an active, evolving system. Each event reshapes the stage for the next.
Understanding these connections is critical for building resilience so communities can withstand future storms, earthquakes and the problems created by debris flows. Better forecasts can inform building codes, guide infrastructure design and improve how risk is priced and managed. They can help communities anticipate long-term threats and adapt before the next disaster strikes.
Most importantly, they challenge everyone to think beyond the immediate aftermath of a disaster—and to recognize the slow, quiet transformations that build toward the next.
Yale University ecologists reveal a lizard lineage that rode out the dinosaur-killing asteroid event with unexpected evolutionary survival traits. Night lizards (family Xantusiidae) survived the Cretaceous–Paleogene (K-Pg) mass extinction event 66 million years ago (formerly known as the K-T extinction) despite having small broods and occupying limited ranges, a departure from the theory of how other species are thought to have persisted in the aftermath of the event.
Before K-Pg, Earth was a warm, thriving planet with lush forests and diverse ecosystems both on land and in the oceans. Dinosaurs were widespread, diverse, and dominant. Marine reptiles patrolled the seas and pterosaurs soared through the skies. Future humans were still shrew-like, tree-dwelling creatures, part of a small but growing evolutionary experiment into placental mammals.
An asteroid more than six miles across, moving around 43,200 miles per hour, struck the Chicxulub region of Yucatán, Mexico, releasing an incomprehensible 1023 joules of energy. For context, if every explosive that humans have ever made all detonated at once, it still wouldn’t come close to the energy released by the Chicxulub asteroid.
A 1,000-mile radius of forest was instantly incinerated by the extreme heat, as the impact gouged a crater more than 100 miles wide and 12 miles deep. Tsunamis, roughly the height of the Eiffel Tower, propagated outward, ravaging shorelines and sea floors across the globe, and rang Earth’s mantle like a bell, setting off what today would be city-leveling mega-earthquakes greater than magnitude 10.
And just when the worst seemed to be over, it got even worse. Debris ejected from the impact that had risen above Earth’s atmosphere began raining back down. Superheated upon reentry, it pelted the planet with a deadly shower of molten projectiles that started global fires.
Vast amounts of soot, dust, and aerosols were left lingering in the stratosphere, blocking sunlight and plunging the planet into an “impact winter” with plummeting global temperatures. Without photosynthesis, plant life began to die off, and food chains from the smallest ocean plankton to largest dinosaurs were obliterated. Acid rain, produced by vaporized sulfur-rich rocks, induced rapid changes in ocean chemistry, which led to the widespread extinction of plankton, ammonites, and many marine reptiles.
When it was over, 75% of species, the products of billions of years of evolution, were gone. It is a wonder that anything at all survived the event, but life did find a way.
In the study, “Night lizards survived the Cretaceous–Paleogene mass extinction near the asteroid impact,” published in Biology Letters, researchers combined phylogenetic tip-dating with ancestral-trait reconstruction to determine whether xantusiid lizards originated before the K-Pg boundary and to identify features that may have aided their survival.
Genetic data from 34 living night-lizard species, integrated with fossils ranging from the Early Cretaceous to Miocene strata across North America, Central America, and Cuba, anchored the analyses.
Genetic clocks traced Cricosaura typica, a Cuban species, to the earliest branch in the family tree, splitting off before its North and Central American cousins emerged. Species of Lepidophyma and Xantusia diversified much later, in parallel radiations about 12 million years ago, long after the asteroid had reshaped their ancestral landscape.
On California’s Channel Islands, the giant island night lizard evolved from a mainland lineage that dispersed west roughly 10 million years back, crossing temporary land bridges before becoming isolated.
Researchers found the 34 living night-lizard species descended from at least two ancient lineages that began roughly 92 million years ago, and survived the K-Pg boundary. Unlike survivors among birds or mammals, these lizards carried forward a life strategy with comparatively small litters.
Statistical reconstruction estimated that ancestral females produced about two offspring at a time, a figure bounded by the single-egg clutches of Cricosaura and the more prolific broods seen in the larger-bodied island species. Body size and fecundity still move in tandem across the lineage, suggesting that bigger litters evolved later, possibly in response to island habitats.
Authors contend that the persistence of night lizards through the Cretaceous–Paleogene extinction event unsettles assumptions about which traits shield lineages from annihilation. Survival did not depend on broad geographic ranges or large broods, qualities often credited in mammals and birds. Instead, night lizards appear to have crossed the extinction threshold while occupying narrow habitats and producing only one or two offspring per reproductive event.
Because of the intensity of K-Pg, there can be no direct fossil evidence that Cretaceous night lizards (or anything else) occupied the immediate impact region. Instead, the inference of proximity rests on reconstructed ancestral ranges in North and Central America and molecular dating placing their common ancestor in the Late Cretaceous. Together, this offers indirect evidence of a front row seat for the most devastating event in Earth’s history.
Insights from these lizards’ survival may refine how scientists project which species are likely to weather rapid environmental shifts, especially as the current, human-driven mass extinction accelerates.
Written for you by our author Justin Jackson, edited by Lisa Lock , and fact-checked and reviewed by Robert Egan —this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You’ll get an ad-free account as a thank-you.
More information: Chase D. Brownstein et al, Night lizards survived the Cretaceous–Palaeogene mass extinction near the asteroid impact, Biology Letters (2025). DOI: 10.1098/rsbl.2025.0157
Squids first appeared about 100 million years ago and quickly rose to become dominant predators in the ancient oceans, according to a study published in the journal Science.
A team of researchers from Hokkaido University developed an advanced fossil discovery technique that completely digitizes rocks with all embedded fossils in complete 3D form. It allowed them to identify one thousand fossilized cephalopod beaks hidden inside Late Cretaceous rocks from Japan. Among these small and fragile beaks were 263 squid specimens, including about 40 different species that had never been seen before.
Squids are rarely preserved as fossils because they don’t have hard shells. Their origin and early evolution are the biggest questions in the 500 million-year history of cephalopods, which have been model animals for long-term evolution. Squid beaks, hard mouthparts that have a high fossilization potential, are therefore important clues for studying how squids evolved.
One of the study’s most striking discoveries was how common squids were in ancient oceans. The team found that squid fossils far outnumbered those of ammonites and bony fishes. Ammonites are extinct shelled relatives of squids and have been considered among the most successful swimmers of the Mesozoic era.
“In both number and size, these ancient squids clearly prevailed the seas,” said Dr. Shin Ikegami of the Department of Earth and Planetary Sciences at Hokkaido University, the study’s first author.
“Their body sizes were as large as fish and even bigger than the ammonites we found alongside them. This shows us that squids were thriving as the most abundant swimmers in the ancient ocean.”
An example of grinding tomography images. Credit: Ikegami et al., Science, June 26, 2025
The research also revealed that the two main groups of modern squids, Myopsida, which live near the shore, and Oegopsida, found in the open sea, were already present around 100 million years ago.
Until now, scientists believed that squids only began to flourish after the mass extinction event that ended the age of dinosaurs about 65 million years ago. The new study shows that squids had already originated and explosively diversified long before then.
The digital fossil-mining method utilizes grinding tomography to create digitized rocks and reveal hidden fossils within them. Credit: Ikegami et al., Science, June 26, 2025
“These findings change everything we thought we knew about marine ecosystems in the past,” said Associate Professor Yasuhiro Iba of the Department of Earth and Planetary Sciences at Hokkaido University, who led the study.
“Squids were probably the pioneers of fast and intelligent swimmers that dominate the modern ocean.”
Chinese Academy of Sciences researchers report that fossilized entomopathogenic fungi from mid-Cretaceous amber reveal some of the oldest direct evidence of parasitic relationships between fungi and insects, suggesting that Ophiocordyceps fungi originated approximately 133 million years ago and underwent early host shifts that shaped their evolution.
Entomopathogenic fungi have evolved extraordinary ways to turn insects into unwitting accomplices in their own demise. Among the most famous are the “zombie ant fungi,” Ophiocordyceps unilateralis, which infect carpenter ants in tropical rainforests. After infecting the ant’s body, the fungus hijacks the host’s nervous system, compelling it to abandon the safety of its nest.
The ant becomes a macabre six-legged marionette, compelled to climb a plant to a height above the colony, where it clamps its jaws onto a leaf. Locked into a final death grip, the ant dies while the fungus slowly consumes its tissues. After a while, a spore-producing stalk erupts grotesquely from the back of the ant’s head, scattering infectious spores down onto the forest floor to restart the cycle with fresh victims.
But ants are far from the only victims of fungal mind control. In grasslands and fields, entomopathogenic fungi like Entomophthora grylli invade grasshoppers and crickets, orchestrating a similar, chilling scenario known as “summit disease.” As infection progresses, the insect abandons its usual behavior, ascending to the tops of grasses or tall weeds. There, it perches in a characteristic posture, often gripping the plant with its legs stretched outward.
As the fungus bursts through the exoskeleton, it releases clouds of spores that drift down onto the unsuspecting insects below. In some cases, related fungi have been observed driving their hosts to wander aimlessly before ultimately walking into streams or ponds, where they drown, ensuring the fungus can grow in the moist environment that best suits it.
Flies, too, fall prey to fungal manipulation. Entomophthora muscae infects common houseflies, also driving them to climb to high spots, upper corners of windows or walls, just before death. There, the fly extends its proboscis to glue itself in place, creating the perfect platform for the fungus to erupt through the soft parts of the body. From the cadaver, spore-laden filaments radiate outward, releasing infectious particles into the air to settle onto new hosts.
Even spiders can be commandeered. Some Ophiocordyceps species compel infected spiders to attach themselves to leaves or twigs before succumbing, ensuring the fungus can safely grow a fruiting body that rains spores into the surrounding habitat.
These remarkable strategies highlight the astonishing evolutionary tactics of parasitic fungi. By reprogramming their hosts’ instincts for climbing, gripping, and walking, they orchestrate ideal conditions for their own reproduction. What appears to be mindless self-destruction by the insect is, in reality, the well-executed plan of a fungus perfectly adapted to exploit its host’s body and behavior.
Direct fossil evidence of these relationships has remained scarce, largely because soft fungal tissues rarely fossilize and their pathogenic nature can be difficult to discern in ancient specimens. Previous research has documented only a handful of tentative fossil records, and estimates of the evolutionary origins of Ophiocordyceps fungi relied on limited calibration points and indirect evidence.
In the study, “Cretaceous entomopathogenic fungi illuminate the early evolution of insect–fungal associations,” published in Proceedings of the Royal Society B: Biological Sciences, researchers described two newly identified fungal species preserved in approximately 99-million-year-old Kachin amber.
One of the two fossil fungi described in the study, Paleoophiocordyceps gerontoformicae, occurred in association with an infected ant pupa encased in mid-Cretaceous Kachin amber dated to about 99 million years ago. Researchers assigned the ant host to the extinct genus Gerontoformica, belonging to the subfamily Sphecomyrminae.
Infection likely began inside the nest, since ant larvae do not leave the nest. Workers may have transported fungal spores into the nest and removed the pupa to maintain colony hygiene just as modern ant colonies do. The fossil pupa possibly represents an early instance of such behavior, with disposal outside the nest preceding resin entombment.
Holotype of P. gerontoformicae sp. nov. (YKLP-AMB−010) from mid-Cretaceous Kachin amber (approx. 99 million years ago) and the comparison with extant Ophiocordyceps fungi. Credit: Proceedings of the Royal Society B: Biological Sciences (2025). DOI: 10.1098/rspb.2025.0407
Morphological features of P. gerontoformicae matched characteristics seen in extant myrmecophilous Ophiocordyceps species. A combination of laterally attached ascoma and asexual traits similar to the Hirsutella clade suggested a position near the base of both myrmecophilous hirsutelloid and O. sphecocephala lineages.
Results indicated that Ophiocordyceps likely emerged during the Early Cretaceous, about 133.25 million years ago, earlier than previously proposed estimates of ~100 million years. Ancestral state reconstructions suggest that the genus initially parasitized beetles before undergoing host shifts to Lepidoptera and Hymenoptera during the Cretaceous. Researchers inferred that these transitions coincided with the diversification of moths and ants, which offered new ecological opportunities for fungal specialization.
The authors concluded that the fossils not only document some of the oldest evidence of insect-pathogenic fungi but also support the view that Ophiocordyceps diversified in tandem with its insect hosts.
Written for you by our author Justin Jackson, edited by Lisa Lock , and fact-checked and reviewed by Robert Egan —this article is the result of careful human work. We rely on readers like you to keep independent science journalism alive. If this reporting matters to you, please consider a donation (especially monthly). You’ll get an ad-free account as a thank-you.
More information: Yuhui Zhuang et al, Cretaceous entomopathogenic fungi illuminate the early evolution of insect – fungal associations, Proceedings of the Royal Society B: Biological Sciences (2025). DOI: 10.1098/rspb.2025.0407
Asteroid 2024 YR4 made headlines earlier this year when its probability of impacting Earth in 2032 rose as high as 3%. While an Earth impact has now been ruled out, the asteroid’s story continues.
The final glimpse of the asteroid as it faded out of view of humankind’s most powerful telescopes left it with a 4% chance of colliding with the moon on 22 December 2032.
The likelihood of a lunar impact will now remain stable until the asteroid returns to view in mid-2028. In this FAQ, find out why we are left with this lingering uncertainty and how ESA’s planned NEOMIR space telescope will help us avoid similar situations in the future.
What is asteroid 2024 YR4?
Asteroid 2024 YR4 was discovered on 27 December 2024 at the Asteroid Terrestrial-impact Last Alert System (ATLAS) telescope in Río Hurtado, Chile.
Shortly after its discovery, automated asteroid warning systems determined that the object had a small chance of potentially impacting Earth on 22 December 2032.
The asteroid is between 53 and 67 meters in diameter. An asteroid of this size impacts Earth on average only once every few thousand years and would cause severe damage to a city or region.
Follow-up observations saw the chance of impact rise to around 3%. As a result, the asteroid shot to the top of ESA’s asteroid risk list and captured global attention as it became the first asteroid to trigger a coordinated international planetary defense response.
Additional observations made over the next few months, including those made using the James Webb Space Telescope, allowed astronomers to more accurately measure the asteroid’s orbit around the sun.
By March 2025, they had enough information to rule out an Earth impact in 2032.
Why did we not detect 2024 YR4 sooner?
2024 YR4 was first discovered two days after it had already passed its closest point to Earth. It was not detected sooner because it approached Earth from the day side of the planet, from a region of the sky hidden by the bright light of the sun.
This region of the sky is hidden from the view of ground-based optical telescopes and is a blind spot for asteroid warning systems.
The significance of this blind spot was made clear on 15 February 2013, when the Chelyabinsk meteor, a 20-meter, 13,000-ton asteroid, struck the atmosphere over the Ural Mountains in Russia during the middle of the day. The resulting blast damaged thousands of buildings, and roughly 1,500 people were injured by shards of glass.
Could we have detected 2024 YR4 sooner?
ESA’s Near-Earth Object Mission in the InfraRed (NEOMIR) satellite, planned for launch in the early 2030s, will cover this important blind spot.
These images of asteroid 2024 YR4 were captured by the NASA/ESA/CSA James Webb Space Telescope in March 2025. Credit: NASA, ESA, CSA, STScI, A Rivkin (JHU APL)
NEOMIR will be equipped with an infrared telescope and positioned at the first sun-Earth Lagrange Point. By relying on infrared light, rather than visible light, NEOMIR can spot asteroids in a region of the sky much closer to the sun. It will repeatedly scan this region for the thermal signatures of asteroids approaching Earth that are at least 20 meters across—like 2024 YR4 and the Chelyabinsk meteor.
“We looked into how NEOMIR would have performed in this situation, and the simulations surprised even us,” says Richard Moissl, Head of ESA’s Planetary Defense Office.
“NEOMIR would have detected asteroid 2024 YR4 about a month earlier than ground-based telescopes did. This would have given astronomers more time to study the asteroid’s trajectory and allowed them to much sooner rule out any chance of Earth impact in 2032.”
“As an infrared telescope, like Webb, NEOMIR would have also immediately given us a much better estimate of the asteroid’s size, which is very important for assessing the significance of the hazard.”
Will asteroid 2024 YR4 impact the moon?
By March 2025, astronomers had ruled out an Earth impact in 2032. However, the final observations of the asteroid failed to rule out another intriguing possibility: a lunar impact.
The probability that asteroid 2024 YR4 will strike the moon on 22 December 2032 is now approximately 4%, and this probability was still slowly rising as the asteroid faded out of view.
However, this means that there is a 96% chance that the asteroid will not impact the moon.
The JANUS camera onboard ESA’s Jupiter Icy Moons Explorer (Juice) is designed to take detailed, high-resolution photos of Jupiter and its icy moons. JANUS will study global, regional and local features and processes on the moons, as well as map the clouds of Jupiter. It will have a resolution up to 2.4 m per pixel on Ganymede and about 10 km per pixel at Jupiter. This image of our own Moon was taken during Juice’s lunar-Earth flyby on 19 August 2024. The main aim of JANUS’s observations during the lunar-Earth flyby was to evaluate how well the instrument is performing, not to make scientific measurements. Credit: ESA/Juice/JANUS
When will we know for sure?
We are left with an interesting situation: there is now a 60 m asteroid with a 4% chance of hitting the moon in 2032. As the asteroid is now too far away to study any further, this probability will remain unchanged until it returns into view in June 2028.
When it does return into view, new observations will be made and it will not take long for astronomers to confidently determine whether the asteroid will, or much more likely, will not, hit the moon on 22 December 2032.
What will happen if the asteroid hits the moon?
“A lunar impact remains unlikely, and no one knows what the exact effects would be,” says Richard Moissl.
“It is a very rare event for an asteroid this large to impact the moon—and it is rarer still that we know about it in advance. The impact would likely be visible from Earth, and so scientists will be very excited by the prospect of observing and analyzing it. I am sure that detailed computational simulations will be done over the next few years.”
“It would certainly leave a new crater on the surface. However, we wouldn’t be able to accurately predict in advance how much material would be thrown into space, or whether any would reach Earth.”
In the coming years, as humankind looks to establish a prolonged presence on the moon, monitoring space for objects that could strike Earth’s natural satellite will become increasingly important.
This image depicts the probability that the asteroid 2024 YR4 will impact Earth’s moon on 22 December 2032. The red dots represent the possible locations of asteroid 2024 YR4 on 22 December 2032. The yellow dot represents its most likely location. The uncertainty region is measured as the distance between the two most separated red dots. One Earth radius is approximately 6378 km. Credit: ESA
Small objects burn up in Earth’s atmosphere as meteors, but the moon lacks this shield. Objects just tens of centimeters in size could pose a significant hazard to astronauts and lunar infrastructure.
What else is ESA doing to improve Europe’s planetary defense capabilities?
The discovery of asteroid 2024 YR4 made it clear that time is of the essence when it comes to asteroid detection. In cases like that of 2024 YR4, the later an asteroid is detected, the less time is available for follow-up observations before it fades from view.
Decision makers need as much information as possible when considering potential mitigation strategies, such as deflection missions or evacuation plans: they do not want to be left with an uncertain but significant chance of Earth impact for multiple years.
By keeping watch for asteroids approaching Earth from the direction of the sun, ESA’s NEOMIR space telescope will fill an important blind spot in our current asteroid detection systems and significantly improve our preparedness for future hazards similar to 2024 YR4.
More information: Follow the links below to find out more about ESA’s other Planetary Defense activities, such as the Near-Earth Object Coordination Center (NEOCC); the Flyeye asteroid survey telescopes; the Hera mission, which will turn asteroid deflection into a well-understood and repeatable technique for planetary defense; and the Ramses mission to intercept and explore the infamous asteroid Apophis as it safely passes close to Earth in 2029.
What processes during the formation of Pluto’s largest moon, Charon, potentially led to it having cryovolcanism, and even an internal ocean? This is what a recent study presented at the 56th Lunar and Planetary Science Conference (LPSC 2025) hopes to address as a team of researchers investigated the formation and evolution of Charon to ascertain whether it once possessed an internal ocean during its history and if this could have led to cryovolcanism based on images obtained by NASA’s New Horizons probe.
For the study, the researchers used a series of computer models to simulate the early conditions on Charon that could have resulted in creating an internal ocean and potentially cryovolcanism, resulting in the southern hemisphere, known as Vulcan Planitia, being resurfaced from cryovolcanism. It is currently hypothesized that Charon collided with Pluto and one goal of this work was to ascertain if Charon first formed before the collision or after.
While only a portion of Charon’s surface was briefly imaged by NASA’s New Horizons spacecraft in July 2015, this limited dataset has provided planetary scientists with intriguing insights into its formation and evolution. This includes kilometers-high scarps that run along the moon’s equator, with the southern hemisphere being more cratered than the northern hemisphere. In the end, the models estimated that Charon’s subsurface ocean likely formed between 370 million and 400 million years ago and fully froze between 2.12 billion years ago and 2.2 billion years ago.
The study notes, “Crucially, in no simulation across any parameter studied so far did the ocean fully freeze in a timeframe consistent with massive cryovolcanic eruptions before 4 Gyr ago. These results strongly suggest that if ocean freezing is the cause of the resurfacing of Vulcan Planitia at 4 Gyr ago, the details of the impact matter.”
Discovered in 1978, Charon is one of the most intriguing moons in the solar system due to being approximately half the diameter of Pluto, which is the largest known satellite relative to its parent body it’s orbiting. For context, Earth’s moon is approximately one-quarter the diameter of Earth. Several hypotheses regarding Charon’s formation and evolution have been proposed, with the most recent being both Pluto and Charon collided billions of years ago, were stuck together, and eventually came apart and formed the two planetary bodies we see today.
Given the enormous distance from Earth at just under 3.2 billion miles, traveling to the Pluto system takes many years, with NASA’s New Horizons taking more than 9.5 years to reach Pluto and Charon for its brief flyby in July 2015. This brief flyby provided scientists with enough data about Pluto and Charon that continues to be pored over today, with scientists continuing to learn more about this intriguing system and how both planetary bodies formed and evolved.
Both planetary bodies are part of the Kuiper Belt, which is a donut-shaped region of icy, rocky objects beyond the orbit of Neptune. While Pluto is the most well-known dwarf planet in the Kuiper Belt, other dwarf planets include Haumea, Makemake, and Eris.
While no follow-up missions to Pluto are currently being planned, several mission concepts are in development, ranging from an orbiter to a lander on Charon’s surface. If a subsurface ocean on Charon is confirmed, even a frozen one, this could challenge our understanding of how planetary bodies form and evolve, especially so far from the sun.
