A fossilized dragonfly wing unearthed in Alberta’s Dinosaur Provincial Park has been identified as a brand-new species, marking the first dragonfly fossil ever found in Canada’s dinosaur-aged rocks. Credit: Alex Anderson
Discovery reveals a previously undocumented 30-million-year gap in dragonfly evolution.
For the first time in Canadian paleontology, a fossilized dragonfly wing from the Cretaceous period has been identified as a new species. Found in Alberta’s Dinosaur Provincial Park, it represents the earliest dragonfly fossil ever recovered from Canada’s dinosaur-era rock layers. The discovery, made by a McGill University research team, helps bridge a 30-million-year gap in the evolutionary record of dragonflies.
The specimen was unearthed in 2023 by a McGill undergraduate student during a vertebrate paleontology field course directed by Prof. Hans Larsson.
A surprising fossil discovery
“We were excavating an area where many leaf fossils had been found by cracking rocks,” said André Mueller, lead author of the study and a Master’s student in Larsson’s lab in McGill’s Department of Biology. “When the partial wing was uncovered, we were taken by surprise as we were not expecting to find any insects there.”
The team named the new species Cordualadensa acorni. Because of its remarkable distinction and unique anatomy, they even created a new family – Cordualadensidae – to classify it. They chose “acorni” for the species name to honor of University of Alberta lecturer John Acorn, entomologist and science communicator at the University of Alberta who has promoted the natural history of Alberta for decades, including with the TV show “Acorn, the Nature Nut.”
Adding to Alberta’s fossil record
“This is the first ever dinosaur-aged dragonfly found in Canada,” said Mueller. “Its wingspan was about the width of a human hand, and while small, it would have been an important part of the Cretaceous ecosystem—a tasty raptor snack, no doubt.”
The fossil was uncovered in the 75-million-year-old Dinosaur Park Formation, a site internationally recognized for its exceptional abundance of dinosaur remains. Until this discovery, however, evidence of insects in the formation was almost entirely absent. The only insect previously reported was a tiny aphid preserved in amber.
“This discovery not only doubles our knowledge of insects from the park, but also represents a completely unknown preservation method, impression fossils, for insect fossils in the area,” said Alexandre Demers-Potvin, a former Larsson PhD student and now a postdoctoral fellow in McGill’s Department of Biomedical Engineering. “We’ve now started finding more insect fossils by expanding where and how we search. The diversity of insect life during this time was likely much greater than we thought.”
The new fossil helps fill a major 30-million-year-old evolutionary gap. It’s the first known North American member of a large group of dragonflies called Cavilabiata. “The wing anatomy tells us this species was adapted for gliding; a trait associated with migratory dragonflies today and possibly a key to their success,” said Larsson. “This specimen also provides insight into what life was like in Canada 75 million years ago, adding an important new missing piece of the ecological puzzle of one of the most diverse dinosaur-bearing sites in the world.”
Reference: “New family of fossil dragonfly (Odonata, Cavilabiata) from the late Cretaceous (Campanian) Dinosaur Park Formation, Alberta, Canada” by André S. Mueller, Alexandre V. Demers-Potvin and Hans C.E. Larsson, 1 August 2025, Canadian Journal of Earth Sciences. DOI: 10.1139/cjes-2024-0162
Funding for fieldwork was supported by an NSERC Discovery Grant (RGPIN/04370-2022) awarded to HCEL. This research was performed using the infrastructure of the Adaptable Earth Observation System, funded by the Quebec government, McGill University, and the Canadian Foundation of Innovation project 36146.
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New research by UAlbany anthropologist Adam D. Gordon finds substantial sexual dimorphism in some of our early human ancestors. Credit: Ken Zirkel from the Museum of Natural History, used by permission
Fossils reveal extreme sexual dimorphism in early hominins. The findings reshape views of their social behavior.
A recent study has revealed that males of some of humanity’s earliest ancestors were much larger than their female counterparts. This marked difference in body size, found in both Australopithecus afarensis (the East African species that includes the well-known fossil “Lucy”) and A. africanus (a closely related species from southern Africa), indicates that these early hominins may have lived in societies where strong competition among males contributed to the pronounced size gap between the sexes.
The research, led by Adam D. Gordon, an anthropologist at the University at Albany, was published in the July issue of the American Journal of Biological Anthropology. By applying a new method that addresses the challenges posed by incomplete fossil evidence, the study demonstrates that both A. afarensis and A. africanus showed greater sexual dimorphism than modern humans — and in some cases, even exceeded the differences seen in gorillas.
“These weren’t modest differences,” said Gordon, an associate professor in the College of Arts and Sciences. “In the case of A. afarensis, males were dramatically larger than females — possibly more so than in any living great ape. And although both of these extinct hominin species exhibited greater sex-specific size differences than modern humans do, they were also more different from each other in this respect than living ape species are, suggesting a greater diversity of evolutionary pressures acting on these closely-related species than we had previously appreciated.”
Interpreting fossils with new methods
The findings provide fresh insight into how the fossil record is interpreted. Previous research had produced conflicting views on dimorphism in A. afarensis, with some studies arguing it was comparable to the relatively modest differences seen in modern humans. Until now, however, scientists had not been able to directly compare fossil species, since earlier analyses were restricted by fragmentary skeletal remains and lacked the statistical strength needed to identify meaningful distinctions.
UAlbany Associate Professor of Anthropology Adam D. Gordon. Credit: Patrick Dodson
“This analysis overcomes these issues by using an iterative resampling method that mimics the missing data structure in both fossil species when sampling from skeletal material of living species, allowing the inclusion of multiple fossil individuals even when those individual specimens are fragmentary,” said Gordon. “This study provides strong evidence that sex-specific evolutionary pressures — likely involving both male competition for mates and resource stress acting more intensely on female size due to the metabolic constraints of pregnancy and lactation — played a larger role in early hominin evolution than previously believed.”
Why Sexual Size Dimorphism Matters
Sexual size dimorphism (SSD) is more than a simple physical difference between males and females — it also reflects patterns of behavior and evolutionary strategy. According to sexual selection theory, high SSD in living primates is usually linked to intense competition between males and social systems where a small number of large males control reproductive access to multiple females. By contrast, low SSD can occur across many species but is most often associated with pair-bonded social systems and reduced competition for mates. In modern human populations, SSD is generally low to moderate: men are slightly larger on average, though there is substantial overlap in body size between the sexes.
Gordon’s earlier research also indicates that high SSD can emerge under conditions of severe resource stress. When food is scarce, smaller but healthy females are often able to meet their nutritional needs and store enough energy for reproduction more effectively than larger females. This can result in greater reproductive success for smaller-bodied females and, over time, a widening size difference between males and females.
The pronounced SSD found in both Australopithecus species suggests strong male competition, much like what is observed in chimpanzees or gorillas. However, the differences in dimorphism between the two species may reflect variations in the intensity of sexual selection pressures or in the degree of environmental stress (for example, differences in the length of dry seasons and their impact on female body size).
Ultimately, the high SSD observed in these fossil hominins stands in contrast to the more balanced size patterns of modern humans. It points to a different model of early hominin life — one in which large body size may have given males a competitive advantage in reproduction, while smaller size in females may have been favored for its energetic efficiency.
How the Research Was Conducted
Fossil data are often fragmentary, and determining the sex of ancient individuals is nearly impossible. To work around this, Gordon used a geometric mean method that allows for size estimation from multiple skeletal elements — including the humerus, femur, tibia, and others. He then applied resampling techniques to simulate thousands of comparisons between fossil hominins and modern primates, ensuring that the statistical models mirrored the incomplete and uneven nature of real fossil samples.
Data from modern gorillas, chimpanzees, and humans with known sex and complete skeletons were used to build a comparative framework.
Unlike past studies, which sometimes interpreted weak or inconclusive statistical results as evidence of similarity, Gordon’s methods revealed clear and significant differences even when using relatively small fossil samples.
To rule out the possibility that body size changes in A. afarensis reflected evolutionary trends rather than sex differences, Gordon also tested for chronological trends across a 300,000-year span of fossils from the Hadar Formation in Ethiopia.
His analysis found no significant size increase or decrease over time, indicating that the observed variation is best explained by differences between males and females — not by evolutionary drift or long-term increases in average size.
Rewriting History
The implications of Gordon’s findings are wide-ranging. Australopithecus afarensis, which lived between 3.9 and 2.9 million years ago, is widely regarded as either a direct ancestor of modern humans or a species very closely-related to a direct ancestor.
Yet, its high degree of sexual dimorphism suggests that early hominins may have lived in social systems that were far more hierarchical and competitive than once thought.
Meanwhile, the less dimorphic A. africanus — which overlapped in time with A. afarensis but first shows up and last appears in the fossil record slightly later, between roughly 3.3 and 2.1 million years ago — may represent a different evolutionary branch on the hominin tree, or perhaps a transitional stage in the development of more human-like social behavior.
“We typically place these early hominins together in a single group called the gracile australopiths, a group of species that are thought to have interacted with their physical and social environments in very similar ways,” Gordon said. “And while that’s true to a certain extent — the evidence suggests that both these species may have had social organizations more like gorillas than modern people — the significant difference in the amount of dimorphism in these two extinct species suggests that these closely-related hominin species were subject to selection pressures more distinct than the selection pressures applied to any pair of similarly closely-related living ape species, highlighting the diversity of ways that our extinct ancestors and close relatives interacted with the world.”
Reference: “Sexual Size Dimorphism in Australopithecus: Postcranial Dimorphism Differs Significantly Among Australopithecus afarensis, A. africanus, and Modern Humans Despite Low-Power Resampling Analyses” by Adam D. Gordon, 11 July 2025, American Journal of Biological Anthropology. DOI: 10.1002/ajpa.70093
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Clues about how worlds like Earth may have formed have been found buried at the heart of a spectacular ‘cosmic butterfly’.
With the help of the James Webb Space Telescope, researchers say they have made a big leap forward in our understanding of how the raw material of rocky planets comes together.
This cosmic dust – tiny particles of minerals and organic material which include ingredients linked to the origins of life – was studied at the core of the Butterfly Nebula, NGC 6302, which is located about 3,400 light-years away in the constellation Scorpius.
From the dense, dusty torus that surrounds the star hidden at the center of the nebula to its outflowing jets, the Webb observations reveal many new discoveries that paint a never-before-seen portrait of a dynamic and structured planetary nebula.
They have been published on August 27 in Monthly Notices of the Royal Astronomical Society.
Most cosmic dust has an amorphous, or randomly oriented-atomic structure, like soot. But some of it forms beautiful, crystalline shapes, more like tiny gemstones.
“For years, scientists have debated how cosmic dust forms in space. But now, with the help of the powerful James Webb Space Telescope, we may finally have a clearer picture,” said lead researcher Dr Mikako Matsuura, of Cardiff University.
“We were able to see both cool gemstones formed in calm, long-lasting zones and fiery grime created in violent, fast-moving parts of space, all within a single object.
“This discovery is a big step forward in understanding how the basic materials of planets, come together.”
The Butterfly Nebula’s central star is one of the hottest known central stars in a planetary nebula in our galaxy, with a temperature of 220,000 Kelvin.
This blazing stellar engine is responsible for the nebula’s gorgeous glow, but its full power may be channeled by the dense band of dusty gas that surrounds it: the torus.
The new Webb data show that the torus is composed of crystalline silicates like quartz as well as irregularly shaped dust grains. The dust grains have sizes on the order of a millionth of a meter — large, as far as cosmic dust is considered — indicating that they have been growing for a long time.
Outside the torus, the emission from different atoms and molecules takes on a multilayered structure. The ions that require the largest amount of energy to form are concentrated close to the center, while those that require less energy are found farther from the central star.
Iron and nickel are particularly interesting, tracing a pair of jets that blast outward from the star in opposite directions.
Intriguingly, the team also spotted light emitted by carbon-based molecules known as polycyclic aromatic hydrocarbons, or PAHs. They form flat, ring-like structures, much like the honeycomb shapes found in beehives.
On Earth, we often find PAHs in smoke from campfires, car exhaust, or burnt toast.
Given the location of the PAHs, the research team suspects that these molecules form when a ‘bubble’ of wind from the central star bursts into the gas that surrounds it.
This may be the first-ever evidence of PAHs forming in a oxygen-rich planetary nebula, providing an important glimpse into the details of how these molecules form.
NGC 6302 is one of the best-studied planetary nebulae in our galaxy and was previously imaged by the Hubble Space Telescope.
Planetary nebulae are among the most beautiful and most elusive creatures in the cosmic zoo. These nebulae form when stars with masses between about 0.8 and 8 times the mass of the Sun shed most of their mass at the end of their lives. The planetary nebula phase is fleeting, lasting only about 20,000 years.
Contrary to the name, planetary nebulae have nothing to do with planets: the naming confusion began several hundred years ago, when astronomers reported that these nebulae appeared round, like planets.
The name stuck, even though many planetary nebulae aren’t round at all — and the Butterfly Nebula is a prime example of the fantastic shapes that these nebulae can take.
The Butterfly Nebula is a bipolar nebula, meaning that it has two lobes that spread in opposite directions, forming the ‘wings’ of the butterfly. A dark band of dusty gas poses as the butterfly’s ‘body’.
This band is actually a doughnut-shaped torus that’s being viewed from the side, hiding the nebula’s central star — the ancient core of a Sun-like star that energises the nebula and causes it to glow. The dusty doughnut may be responsible for the nebula’s insectoid shape by preventing gas from flowing outward from the star equally in all directions.
The new Webb image zooms in on the center of the Butterfly Nebula and its dusty torus, providing an unprecedented view of its complex structure. The image uses data from Webb’s Mid-InfraRed Instrument (MIRI) working in integral field unit mode.
This mode combines a camera and a spectrograph to take images at many different wavelengths simultaneously, revealing how an object’s appearance changes with wavelength. The research team supplemented the Webb observations with data from the Atacama Large Millimeter/submillimeter Array, a powerful network of radio dishes.
Researchers analyzing these Webb data identified nearly 200 spectral lines, each of which holds information about the atoms and molecules in the nebula. These lines reveal nested and interconnected structures traced by different chemical species.
The research team were able to pinpoint the location of the Butterfly Nebula’s central star, which heats a previously undetected dust cloud around it, making the latter shine brightly at the mid-infrared wavelengths that MIRI is sensitive to.
The location of the nebula’s central star has remained elusive until now, because this enshrouding dust renders it invisible at optical wavelengths. Previous searches for the star lacked the combination of infrared sensitivity and resolution necessary to spot its obscuring warm dust cloud.
The paper ‘How is cosmic dust, the raw material of rocky planets and a key ingredient for life, formed in space?’ by Mikako Matsuura et al. has been published in Monthly Notices of the Royal Astronomical Society.
Webb is the largest, most powerful telescope ever launched into space. Under an international collaboration agreement, ESA provided the telescope’s launch service, using the Ariane 5 launch vehicle. Working with partners, ESA was responsible for the development and qualification of Ariane 5 adaptations for the Webb mission and for the procurement of the launch service by Arianespace. ESA also provided the workhorse spectrograph NIRSpec and 50% of the mid-infrared instrument MIRI, which was designed and built by a consortium of nationally funded European Institutes (The MIRI European Consortium) in partnership with JPL and the University of Arizona.
Webb is an international partnership between NASA, ESA and the Canadian Space Agency (CSA).
Researchers told Science Alert that Spicomellus was virtually bristling with bony spikes of all shapes and sizes:
• Rib spikes – sharp projections fused directly to ribs, a feature never seen in any other animal.
• Neck collar – an elaborate ring of meter-long spikes sticking outward like a crown of weapons.
• Hip armour – a pelvic shield with giant outward-facing spikes.
• Tail weapon – fused vertebrae suggesting a spiked club developed at least 30 million years earlier than thought.
“It was spikier than a punk rave,” quipped paleontologist Richard Butler of the University of Birmingham, who co-led the study published in Nature.
Dr. Susannah Maidment of London’s Natural History Museum told Science Alert: “I’ve spent my career working on armoured dinosaurs, but I’d never seen anything like this. At that moment I realised we were looking at something unlike anything anyone had ever found before.”
According to CNN, scientists now suspect the armour was used for display — much like a peacock’s tail or a deer’s antlers. These flamboyant features may have played a role in courtship rituals, territorial dominance, or mating competitions.
“The armour surely had some defensive function, but it’s difficult to imagine how the spikes were used for defence. They seem like enormous overkill,” Butler told CNN.
Filling gaps in dinosaur evolution
The discovery, both outlets note, rewrites what we know about ankylosaur evolution. Normally, early members of a dinosaur group are simpler, with complexity developing later. But Spicomellus flips that assumption: The most elaborate armour of all came at the very start of the ankylosaur lineage.
This also marks the first ankylosaur discovered in Africa. Previously, the species was known only from a single rib fragment described in 2021. New excavations in 2022 and 2023 revealed much more, thanks in part to a Moroccan farmer who safeguarded bones from floodwaters, according to Science Alert.
However, scientists caution that fossil poaching in Morocco threatens research. Science Alert reported that some Spicomellus bones have already appeared for sale in Europe, possibly from the same individual described in the new study. To protect future discoveries, researchers are keeping excavation sites secret.
Scientists have traced the brightest known fast radio burst to its origin in space, a milestone achievement they hope will provide clues about what’s driving these mysterious cosmic flashes.
The powerful signal, FRB 20250316A, was first spotted in March by the Canadian Hydrogen Intensity Mapping Experiment, or CHIME, a radio telescope in British Columbia. The burst lasted less than one-thousandth of a second but carried more energy than the sun produces in four days.
What set this event apart was what happened next. Using a new network of CHIME “Outrigger” stations — three miniature versions of the radio antenna in California, West Virginia, and British Columbia — researchers were able to home in on the burst’s location. That led them to a specific spot in the spiral galaxy NGC 4141, about 130 million light-years away in the Big Dipper constellation.
Scientists say that kind of accuracy is unprecedented for a single burst of this magnitude. Amanda Cook, a McGill University researcher who led one of the studies, likened the precision to spotting a quarter from more than 60 miles away.
“This result marks a turning point: Instead of just detecting these mysterious flashes, we can now see exactly where they’re coming from,” Cook said in a statement. “It opens the door to discovering whether they’re caused by dying stars, exotic magnetic objects, or something we haven’t thought of yet.”
SEE ALSO:
NASA spacecraft snaps photo of Earth from across the solar system
Fast radio bursts, or FRBs, were first discovered in 2007, and thousands have been detected since. They are super-short flashes of radio energyfrom distant galaxies. Historically, they have vanished too quickly to analyze — faster than the blink of an eye — leaving their origins uncertain.
But this radio burst, nicknamed RBFLOAT for Radio Brightest Flash of All Time, was so powerful, it gave researchers that chance. Several teams quickly mobilized to investigate, producing two papers that appear in The Astrophysical Journal Letters.
Mashable Light Speed
“It was so bright that our pipeline initially flagged it as radio frequency interference, signals often caused by cell phones or airplanes that are much closer to home,” said Wen-fai Fong, a coauthor from Northwestern University, in a statement. “It took some sleuthing by members of our collaboration to uncover that it was a real astrophysical signal.”
The CHIME team provided the initial detection and pinpointed the signal’s origin. Astronomers at the W. M. Keck Observatory in Hawaii and the MMT Observatory in Arizona then studied the host galaxy and found that the burst came from just outside a star-forming region. Because the area was relatively clear of gas and dust, telescopes could get a rare, unobstructed view.
Meanwhile, scientists using theJames Webb Space Telescope, a collaboration of NASA and its European and Canadian counterparts, examined the same spot in invisible infrared light and detected a faint glow. They think it could be a red giant — a puffed-up old star — or even residual heat from the radio blast itself. This marked the first time a possible stellar companion has been linked directly to a fast radio burst.
“This was a unique opportunity to quickly turn JWST’s powerful infrared eye on the location of an FRB for the first time,” said Peter Blanchard, a Harvard researcher who led the Webb study, in a statement. “And we were rewarded with an exciting result — we see a faint source of infrared light very close to where the radio burst occurred. This could be the first object linked to an FRB that anyone has found in another galaxy.”
The observations taken together point to magnetars — super-magnetic dead-star remnants — as leading candidates for producing RBFLOAT (Get it? Like a root beer float). CHIME researchers saw that the burst’s position, near a nursery of young stars, fits the mold of a magnetar that formed inside the stellar clump and drifted outward.
CHIME collaboration astronomers observe construction of one of the three new Outrigger Telescopes in northern California. Credit: University of Toronto / Juan Mena-Parra
Still, Webb’s team cautioned that other explanations, such as activity in a binary star system, remain possible.
Adding to the intrigue, CHIME scientists reviewed six years of data and found no previous signals from this location. That suggests RBFLOAT may have been a one-time explosion, bolstering the idea that multiple catalysts could potentially trigger these bursts. Some fast radio bursts repeat often, while others, like this one, appear to be isolated events.
The achievement also showcases the growing capability of new telescope networks. By linking antennas, the CHIME/Outrigger system essentially functions as one giant continent-wide telescope. That allowed astronomers to shrink the uncertainty of RBFLOAT’s position to within 45 light-years — smaller than a single star cluster.
Scientists say this is just the beginning. CHIME is expected to trace hundreds of bursts each year. With Webb and ground-based observatories ready to follow up, astronomers hope to finally learn what powers these fleeting but colossal explosions.
“This bodes very well for the future,” Fong said. “An increase in event rates always provides the opportunity for discovering more rare events.”
NASA’s Gemini and Mercury missions marked a key moment in both the history of crewed spaceflight and the Cold War ‘race to space’ between the USA and the Soviet Union.
The American astronauts who trained and flew into space as part of these programmes were responsible for the USA’s giant leap to overtake the Soviets’ spacefaring prowess, proving that NASA could indeed launch humans into space and return them safely.
John Glenn, Alan Shepard, Neil Armstrong and Buzz Aldrin are among the most famous names in human spaceflight, and each of them cut their teeth on the Mercury and Gemini missions.
SQUIRREL_13317378
Buzz Aldrin is revealed as he takes the first ever selfie in space on Gemini 12, 12th November, 1966. Left and right show the ‘before and after’ versions of the image, as featured in Gemini and Mercury Remastered by Andy Saunders. Credit NASA / ASU / Andy Saunders
Perhaps just as famous as the Mercury and Gemini missions – if not more so – are the images captured by those astronauts from Earth orbit.
These incredible pictures gave humanity the first real glimpse of Earth from the vantage point of space, and showed us what it would be like to travel into orbit.
Andy Saunders is an expert in digital restoration who specialises in working with archive NASA images.
For his latest book, Gemini and Mercury Remastered, Saunders got access to the raw images captured during those early NASA missions, digitally processing them with modern technology them to reveal the photos in a new light.
We caught up with Saunders to find out more about the restoration process, and what sort of images we can look forward to from future Moon missions.
What made the Gemini and Mercury missions so special?
They marked the very beginning of human space exploration, our first bold steps beyond Earth.
Since the dawn of civilisation we’ve looked up and dreamt of flying among the stars, and it was this golden era in the early 1960s when that ancient dream finally became reality.
We were also able to look back at our home planet for the very first time, gaining a vital new perspective.
Mercury were one-man missions in tiny capsules, and the objective was to prove we could get a human into space and back safely.
The rudimentary-looking Gemini spacecraft, Earth, and the bright, white sunlight captured during a spacewalk by Gene Cernan on Gemini 9A, 5th June, 1966. Credit NASA / ASU / Andy Saunders
Within weeks of the first Mercury flight, President Kennedy set the goal of landing a man on the Moon by the end of the decade.
It was then largely down to Gemini to demonstrate a Moon landing was even possible.
With larger, two-man capsules, the missions tested crucial techniques: rendezvous, docking, spacewalking and long-duration flight, all still fundamental to spaceflight today.
They were also incredibly daring missions, conducted at an astonishing pace, truly pushing the boundaries, so they are filled with extraordinary human drama and risk.
I wrote the book not just to showcase the stunning imagery, but also to help tell these stories.
Alan Shepard is waiting atop his Mercury-Redstone rocket, to become the second human, and first American in space, 5th May, 1961. Credit: NASA / Andy Saunders
How did you approach the restoration process?
The starting point for the still photographs are scans of the original film.
Considered too important to handle repeatedly, NASA created duplicates and sealed away the originals.
Unfortunately, most reproductions to date have been based on these lower-quality copies. The images often looked dull and lifeless. A tragedy, given what they represent.
Thankfully, NASA unsealed the original film and digitally scanned it. For the first time, we’re working from the raw light captured through those spacecraft windows over sixty years ago.
Not a distant planet seen in a sci-fi movie, but real life. Our Earth, photographed from Gemini 11, 14th September 1966. Credit NASA / ASU / Andy Saunders
The raw files aren’t ready-to-view straight from the scanner, but buried within them is an extraordinary amount of visual information, just waiting to be revealed by applying digital processing, and some time and effort.
Alongside the still photos, I worked with the 16mm motion picture film.
The format is naturally low-res and noisy, so I used a technique akin to image stacking.
Ed White floats in the void during the first U.S. spacewalk on Gemini 4, 3rd June 1965. Credit NASA / ASU / Andy Saunders
It’s painstaking work, especially with motion in the frame, but the payoff is seeing these pivotal moments in history as never before.
And when colour leaps to life, when long-lost detail reappears, it’s a thrill. It feels like archaeology: brushing dust off a hidden treasure and revealing something extraordinary buried for decades.
Absolutely no AI has been used. The objective is not to embellish, re-imagine or invent, but to restore and bring clarity, to simply peel back the layers of age, decay and duplication, and present these images as vividly and faithfully as possible.
Ed White floats in the void, during the first U.S. spacewalk on Gemini 4, 3rd June 1965. Credit NASA / ASU / Andy Saunders
How do the Mercury and Gemini images compare to contemporary astronaut images?
Mercury and Gemini took not only some of the first, but also some of the finest photographs of Earth ever captured on film.
Of course contemporary ISS photography is all digital. Astronauts now have the luxury of time during missions and the limitless shots digital affords, not to mention as many lenses and filters as you could want.
What photographer wouldn’t dream of sitting in that cupola for hours experimenting? In the early days, with a finite number of exposures, every shot counted.
Three separate remastered photographs, stitched together, showing Florida, an uncrewed Agena target vehicle and the open Gemini hatch (right), during Buzz Aldrin’s spacewalk on Gemini 12, 12th November 1966. Credit NASA / ASU / Andy Saunders
Gemini’s biggest advantage for Earth photography was altitude. While the International Space Station is limited to around 400km (250 miles), Gemini reached over 1,290km (800miles).
Gemini 11’s orbit altitude record stood for 58 years, only narrowly broken in 2024 by Polaris Dawn.
ISS imagery is objectively stunning, but there’s something incredibly intoxicating about early spaceflight photos.
They have a unique aesthetic, clearly referenced in modern sci-fi. The suits and spacecraft look retro yet somehow futuristic.
And the internal shots, now restored, of these brave astronauts risking everything, have an emotional depth that may never be replicated.
All this, combined with the warmth and tonal richness of film, perfectly captures the era.
Gemini 7 is photographed at close quarters from Gemini 6A, during the world’s first space rendezvous (two vehicles meeting in space). Credit NASA / ASU / Andy Saunders
Are you looking forward to the images from the Artemis moonlandings?
Oh I can’t wait. I was born just after Apollo so this will be the first time I can experience such amazing voyages and human exploration of this magnitude.
Having spent some time with the Artemis II crew, I know they’re very aware of the importance of photography and will do a fantastic job.
The eventual landings will be live-streamed in high resolution, there’ll be 360 degree views, helmet cams and all manner of ways to experience it.
My only concern is whether there will be almost too much imagery. Will we become desensitised to it?
In today’s digital age we take 5 billion photographs every day and are constantly bombarded with media.
Photographs have become so transient, enjoyed for a second then gone with the swipe of a finger.
There’s something very special about the finite nature of film, and even waiting for missions to return to Earth before the images could be viewed.
There’s no doubt the new imagery will be incredible, but whether it can match that romance and warmth of early human space exploration on film, remains to be seen.
Wave clouds illuminated by the low Sun like a golden fire as Gemini 7 passes over Earth’s terminator (day to night) on 12th December 1965. Credit NASA / ASU / Andy Saunders
How do you think an image restorer, 100 years from now, will look back on today’s spaceflight photography?
Today’s imagery can still be improved. Noise remains a key enemy with digital. Think how much we can enhance our planetary views from telescopes.
And while technology will continue to evolve, the core need for human creativity and storytelling won’t change.
But in 100 years, the surprise may be how little we were able to truly experience, rather than just view, imagery today.
The future will likely be 3D: VR, AR, maybe even holograms. We’ll ‘walk around’ Mars landers and take in alien vistas from every angle, in real time.
What worries me is authenticity, the growing reliance on AI to create these experiences.
Buzz Aldrin is seen clinging to the spacecraft during his spacewalk as he orbits Earth at over 17,000mph on Gemini 12, 13th November 1966. Credit NASA / ASU / Andy Saunders
What are we really looking at? When AI is applied to imagery, it loses much of its provenance.
Then there’s preservation: how will these technologies and this visual history remain accessible over time?
Most importantly, there’s the inherent content and what it represents.
I’d like to think Gemini and Mercury Remastered is more than a restoration project.
It’s the visual record and the story of when we humans first left Earth, seen through the eyes of those who risked all to make it happen.
Gemini and Mercury Remastered by Andy Saunders is published by Particular Books, an imprint of Penguin Random House.
Newly discovered teeth from Ethiopia reveal that early humans coexisted with a mysterious cousin species, reshaping our understanding of human origins. Credit: Shutterstock
Fossils uncovered in northeastern Ethiopia, dating to between 2.6 and 2.8 million years ago, provide new insights into the course of human evolution.
An international team of researchers has uncovered new fossils in Africa showing that Australopithecus and the earliest known members of Homo lived in the same region at the same time, between 2.6 and 2.8 million years ago. Among the finds was a previously unknown species of Australopithecus, unlike any identified before.
The discoveries come from the Ledi-Geraru Research Project, led by scientists at Arizona State University. This site has already produced the world’s oldest known Homo specimen, as well as the earliest examples of Oldowan stone tools.
The 13 fossil teeth collected in the Ledi-Geraru Research Area from 2015 to 2018. The collections at LD 750 and LD 760 localities represent a newly discovered species of Australopithecus. LD 302 and AS 100 represent early Homo already known from the LD 350 mandible discovered in 2013. Credit: Brian Villmoare/University of Nevada, Las Vegas
Detailed study of the newly recovered Australopithecus teeth confirmed that they represent a distinct species rather than belonging to Australopithecus afarensis, the species of the famous fossil “Lucy.” This finding reinforces that no remains of Lucy’s lineage are known to be younger than 2.95 million years.
“This new research shows that the image many of us have in our minds of an ape to a Neanderthal to a modern human is not correct — evolution doesn’t work like that,” said ASU paleoecologist Kaye Reed. “Here we have two hominin species that are together. And human evolution is not linear, it’s a bushy tree, there are life forms that go extinct.”
“These are teeth from Turtle Flat as we were discovering them — you can see what the ground behind looked like, and how amazing it was that Omar Abdulla first saw them on the surface,” said Amy Rector, Virginia Commonwealth University scientist. Credit: Amy Rector, Virginia Commonwealth University
A research effort spanning decades
Reed serves as a Research Scientist at the Institute of Human Origins and is a President’s Professor Emerita in the School of Human Evolution and Social Change at Arizona State University. She has also co-directed the Ledi-Geraru Research Project since 2002.
So what fossils helped shape these new conclusions? The team uncovered 13 teeth in total.
The Ledi-Geraru site has drawn attention before. In 2013, Reed and her colleagues reported the discovery of the earliest known Homo fossil—a jaw dating to 2.8 million years ago. The new study builds on that legacy, describing additional teeth from the site that belong to both the genus Homo and a newly identified species of Australopithecus.
University of Arkansas Associate Professor Lucas Delezene compares one of the incisors the team discovered to an Australopithecus maxilla (upper jaw) from Hadar at the National Museum of Ethiopia. Credit: Amy Rector
“The new finds of Homo teeth from 2.6 – 2.8 million-year-old sediments, reported in this paper, confirm the antiquity of our lineage,” said Brian Villmoare, lead author and ASU alumnus.
“We know what the teeth and mandible of the earliest Homo look like, but that’s it. This emphasizes the critical importance of finding additional fossils to understand the differences between Australopithecus and Homo, and potentially how they were able to overlap in the fossil record at the same location.”
The team cannot name the species yet based on the teeth alone; more fossils are needed before that can happen.
How do scientists know these fossil teeth are millions of years old?
Volcanoes.
The Afar region remains an active rift zone, marked by frequent volcanic and tectonic activity. When these volcanoes erupted, they released ash containing crystals known as feldspars, which provide scientists with a way to determine their age, explained Christopher Campisano, a geologist at ASU.
Ledi-Geraru paleontological team searching for fossils in the Lee Adoyta Basin, where the genera Homo and Australopithecus have been recovered. Credit: Kaye Reed, Arizona State University
“We can date the eruptions that were happening on the landscape when they’re deposited,” said Campisano, a Research Scientist at the Institute of Human Origins and Associate Professor at the School of Human Evolution and Social Change.
“And we know that these fossils are interbed between those eruptions, so we can date units above and below the fossils. We are dating the volcanic ash of the eruptions that were happening while they were on the landscape.”
Maps showing (left) the location of the Ledi‑Geraru site within the Horn of Africa, and (right) the location of the Australopithecus and Homo teeth. Credit: Erin DiMaggio
Ledi-Geraru’s ancient landscape
Finding fossils and dating the landscape not only helps scientists understand the species, but it also helps them recreate the environment millions of years ago. The modern faulted badlands of Ledi-Geraru, where the fossils were found, are a stark contrast to the landscape these hominins traversed 2.6 – 2.8 million years ago. Back then, rivers migrated across a vegetated landscape into shallow lakes that expanded and contracted over time.
Ramon Arrowsmith, a geologist at ASU, has been working with the Ledi-Geraru Research Project since 2002. He explained the area has an interpretable geologic record with good age control for the geologic time range of 2.3 to 2.95 million years ago.
From left: Arizona State University Professor Ramon Arrowsmith, President’s Professor Emeritus Kaye Reed and Associate Professor Christopher Campisano discussing the Homo teeth that were found in the Asboli, an area at the Ledi‑Geraru site. Credit: Eric Scott
“It is a critical time period for human evolution as this new paper shows,” said Arrowsmith, professor at the School of Earth and Space Exploration. “The geology gives us the age and characteristics of the sedimentary deposits containing the fossils. It is essential for age control.”
Reed said the team is examining tooth enamel now to find out what they can about what these species were eating. There are still remaining questions the team will continue to work on.
Were the early Homo and this unidentified species of Australopithecus eating the same things? Were they fighting for or sharing resources? Did they pass each other daily? Who were the ancestors of these species?
No one knows – yet.
Ledi‑Geraru research team, 2025. Credit: Amy Rector
“Whenever you have an exciting discovery, if you’re a paleontologist, you always know that you need more information,” said Reed. “You need more fossils. That’s why it’s an important field to train people in and for people to go out and find their own sites and find places that we haven’t found fossils yet.”
“More fossils will help us tell the story of what happened to our ancestors a long time ago — but because we’re the survivors, we know that it happened to us.”
Reference: “New discoveries of Australopithecus and Homo from Ledi-Geraru, Ethiopia” by Brian Villmoare, Lucas K. Delezene, Amy L. Rector, Erin N. DiMaggio, Christopher J. Campisano, David A. Feary, Baro’o Mohammed Ali, Daniel Chupik, Alan L. Deino, Dominique I. Garello, Mohammed Ahmeddin Hayidara, Ellis M. Locke, Omar Abdulla Omar, Joshua R. Robinson, Eric Scott, Irene E. Smail, Kebede Geleta Terefe, Lars Werdelin, William H. Kimbel, J. Ramón Arrowsmith and Kaye E. Reed, 13 August 2025, Nature. DOI: 10.1038/s41586-025-09390-4
Funding: U.S. National Science Foundation
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Roughly 390 million years ago, the ancient seas witnessed a dramatic change. Marine animals began moving into deeper waters that had long been uninhabitable. New research suggests this expansion was fueled by a lasting rise in deep-ocean oxygen.
The source of that oxygen traces back to the spread of woody plants on land, the earliest forests on Earth. This environmental shift coincided with an explosion of new species, especially jawed fish.
These fish became the ancestors of nearly all vertebrates alive today. The link between oxygen levels and evolutionary diversification offers fresh insight into how life reshaped the oceans.
Oxygen rise shaped evolution
“It’s known that oxygen is a necessary condition for animal evolution, but the extent to which it is the sufficient condition that can explain trends in animal diversification has been difficult to pin down,” said co-lead author Michael Kipp, assistant professor at Duke University.
“This study gives a strong vote that oxygen dictated the timing of early animal evolution, at least for the appearance of jawed vertebrates in deep-ocean habitats.”
For decades, scientists believed deep-ocean oxygenation occurred only once, at the start of the Paleozoic Era about 540 million years ago.
Later evidence pointed instead to multiple phases. First, shallower waters became livable for breathing organisms, and only later did oxygen reach deeper environments.
Rocks reveal ocean oxygen history
Kipp and his colleagues focused on timing by studying sedimentary rocks once buried beneath ancient oceans.
They measured levels of selenium, an element that records traces of oxygen in the environment. Selenium occurs in different isotopes, and their ratios reveal whether oxygen levels were high enough to support animal life.
The team collected 97 rock samples dating from 252 to 541 million years ago, gathered from five continents.
At the time, these sites lay along outer continental shelves, the zones where land tapered into the ocean before plunging steeply downward. By analyzing isotope ratios in the samples, the researchers tracked oxygen’s reach through time.
Two deep-sea oxygen waves
Results showed two distinct deep-ocean oxygenation events. One brief episode occurred during the Cambrian period, about 540 million years ago.
The second began during the Middle Devonian, around 393 to 382 million years ago, and continues today. Between these events, oxygen dropped to inhospitable levels for most animals.
“The selenium data tell us that the second oxygenation event was permanent. It began in the Middle Devonian and persisted in our younger rock samples,” said co-lead author Kunmanee “Mac” Bubphamanee, a Ph.D. candidate at the University of Washington.
Vertebrates thrived with more oxygen
The Middle Devonian oxygen rise triggered what scientists call the “mid-Paleozoic marine revolution.” With oxygen now plentiful, jawed fish and other animals expanded into deeper waters and diversified.
Fossil evidence also shows that many species grew larger, likely supported by the richer oxygen supply. One example is shown in the featured image of this article – a prehistoric jawed fish from the Late Devonian called Dunkleosteus.
This geological shift aligned with another event on land: the spread of woody plants.
“Our thinking is that, as these woody plants increased in number, they released more oxygen into the air, which led to more oxygen in deeper ocean environments,” Kipp said.
First oxygen wave faded fast
The earlier Cambrian oxygen surge remains puzzling. Its decline likely prevented animals from permanently establishing themselves in deeper waters at that time.
“What seems clear is that the drop in oxygen after that initial pulse hindered the spread and diversification of marine animals into those deeper environments of the outer continental shelves,” Kipp noted.
Oxygen history warns about today’s oceans
Although the study looks far into the past, its message carries urgency now.
“Today, there’s abundant ocean oxygen in equilibrium with the atmosphere,” said Kipp. “But in some locations, ocean oxygen can drop to undetectable levels.”
“Some of these zones occur through natural processes. But in many cases, they’re driven by nutrients draining off continents from fertilizers and industrial activity that fuel plankton blooms that suck up oxygen when they decay.”
“This work shows very clearly the link between oxygen and animal life in the ocean. This was a balance struck about 400 million years ago, and it would be a shame to disrupt it today in a matter of decades.”
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Featured image: An artist’s rendering of a prehistoric jawed fish from the Late Devonian called Dunkleosteus. These sorts of large, active vertebrates evolved shortly after the deep ocean became well-oxygenated. Credit: 2008 N. Tamura/CC-BY-SA
The study is published in the journal Proceedings of the National Academy of Sciences.
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