A bird that was eaten and partially excreted by a dinosaur 66 million years ago has left behind the best-preserved feathers ever recovered by scientists from dinosaur-age rock. This pushes the聽evolution聽of feathers, like the ones on modern birds, back by 10 million years and may tell us more about why most birds didn鈥檛 survive the post-asteroid mass extinction.

鈥淭his is the best feather we鈥檝e ever seen in a Mesozoic [252 million to 66 million years ago] deposit,鈥� says at the Field Museum in Chicago. 鈥淸It鈥檚] like a feather you could pick up off the ground.鈥�

Birds were the only dinosaurs to survive the mass extinction triggered by an asteroid strike 66 million years ago. But, puzzlingly, only one branch made it through: neornithes, the ancestors of every bird alive today.

In 2016, at the University of Washington in Seattle was collecting fish fossils in north-eastern Montana鈥檚 Hell Creek Formation when he discovered a broken coprolite, a fossilised dropping, with a feather clearly visible along its fractured surface. 鈥淚 couldn鈥檛 believe what I was seeing,鈥� he says.

A few years later, he invited O鈥機onnor to team up with him and his colleagues to analyse the coprolite using micro-CT scans and 3D surface scanning. Two leg-bone fragments, 18 and 12 millimetres long, resembled some previously found at Hell Creek and attributed to hesperornithiformes. These were flightless, short-winged diving birds, similar to modern loons (Gaviiformes) or grebes (Podicipediformes), and were related to Neornithes.

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Further analyses showed that the 9.3-millimetre-long primary feather had a water-repellent structure, similar to that of modern pelicans, says O鈥機onnor. Both this and a second, smaller wing feather also had lightweight, spongy cores surrounded by a harder outer layer. This combination makes them both light and stiff, which is typical of modern feathers.

鈥淲hat is exciting is to push the occurrence of modern feathers into non-modern birds,鈥� says O鈥機onnor. Differences in plumage are emerging as a major contributing factor as to why some birds survived while others didn鈥檛, she says.

The team also found two fluffy body feathers with loosely arranged branches, echoing in a lineage that didn鈥檛 survive the extinction event.

Combined, this suggests that the bird the feather belonged to 鈥� and hesperornithiformes in general 鈥� had a 鈥渕iddle ground鈥� of primitive and modern plumage, says O鈥機onnor. While the wing and tail feathers might have allowed for successful diving, for example, the less advanced body feathers would have been relatively poor insulators, making the animals more vulnerable to the 鈥渨inter鈥� that occurred after the asteroid impact.

鈥淭hese are the feathers that are responsible for keeping the body warm, right?鈥� says O鈥機onnor. 鈥淪o maybe these primitive feathers were good enough to keep them warm during the greenhouse world of the Mesozoic, but not good enough to keep them warm during this environmental catastrophe that was triggered by this impact event.鈥�

Dinosaur hunting in the Gobi desert: Mongolia

Embark on an exhilarating and one-of-a-kind expedition to uncover dinosaur remains in the vast wilderness of the Gobi desert, one of the world鈥檚 most famous palaeontological hotspots.

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The dropping 鈥� which probably came from a Nanotyrannus or a young Tyrannosaurus rex 鈥� also contained two rigid, diamond-shaped scales, 3 to 4 millimetres long. The researchers think this came from a gar (Lepisosteidae), a narrow-bodied fish that still exists today. This would have been too small for the dinosaur predator and thus was probably eaten by the bird.

鈥淭his discovery is really exciting,鈥� says at the University of Connecticut. 鈥淚t opens up so many questions about how feathers evolved, what they were originally used for, and how they came to perform so many different functions in modern birds.鈥�

The links among the different animals involved are also fascinating, says Muzio. 鈥淒iscoveries like this really make the imagination run wild,鈥� he says. 鈥淔rom a single coprolite, we are learning about at least three individual species 鈥� morphologically, ecologically and evolutionarily. What more can you ask for?鈥�

People with chronic lung disease breathe better after two months of laughter therapy, results from a small trial show. The promising results may prompt further research into the low-cost treatment option.

In chronic obstructive pulmonary disease (COPD) 鈥� a leading cause of disability and death worldwide 鈥� air isn鈥檛 fully expelled when exhaling, meaning stale air remains trapped inside the lungs. The millions of people who are affected by the condition often feel breathless, even during simple daily activities.

Doctors treat COPD with medications like bronchodilators and corticosteroids, and may also recommend specialised breathing exercises. These include pursed-lip breathing, in which patients breathe in through the nose and out slowly through the lips, which creates a gentle build-up of pressure that helps release some of the air trapped in the lungs. But many people with COPD continue to become increasingly dependent on others for care over time, reducing their quality of life.

, formerly at Hacettepe University Faculty of Nursing in Ankara, Turkey, had seen research showing that laughter therapy shows promise in people with , and and thought it might help those with COPD as well 鈥� both physically and mentally.

To find out, she and her colleagues recruited 63 people who were already being treated for COPD at Ankara Bilkent City Hospital and divided them into three groups of 21. In their randomised controlled trial, all participants continued their medications, but those in one group additionally performed pursed-lip breathing exercises and those in another group received laughter therapy. Participants in the third, control, group did neither.

The laughter therapy is an established programme that differs from simple responses to humour. It includes playful exercises like mimicking a motorcycle starting or a lion roaring, rhythmic clapping with vocal sounds and relaxation with calm breathing and smiling. The participants were coached by laughter therapists in face-to-face sessions and then instructed to perform the techniques on their own for 30 minutes, three times per week.

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After eight weeks, participants in the laughter therapy and the pursed-lip breathing groups had less difficulty breathing and better overall health than those in the control group. Those benefits were still ongoing even a month after the trial ended, says Aldan. Even so, the therapies didn鈥檛 change how much daily assistance participants needed from caregivers. Aldan and her colleagues didn鈥檛 directly compare the effects of pursed-lip breathing and laughter therapy. They at the European Respiratory Society (ERS) Congress in Barcelona, Spain.

While more research could help clarify exactly how laughter therapy helps, Aldan suspects it might exercise the breathing muscles, promote deeper exhalation, improve lymphatic flow and trigger the release of endorphins, while also lowering levels of stress hormones.

鈥淭his structured approach may help facilitate gentle air expulsion and reduce air trapping without overwhelming the respiratory system,鈥� she says. 鈥淧sychologically, it can also offer a safe, enjoyable way to reduce anxiety and support emotional wellbeing.鈥�

Laughter therapy really could boost your emotional well-being

Structured interventions that encourage a good giggle, whether they are laughter yoga or clown visits, could have health benefits

Importantly, however, laughter therapy is distinct from intense or unguided laughter 鈥� like the response to a funny social media video 鈥� which can actually trigger adverse effects like acute airway collapse or exertion, says Aldan. 鈥淟aughter therapy is not merely 鈥榣aughing鈥� 鈥� it is a structured protocol that naturally incorporates deep breathing exercises and rhythmic warm-ups to prepare the lungs and body for laughter.鈥�

鈥淭his is a small but well-run study,鈥� says at Vall d鈥橦ebron University Hospital in Barcelona, Spain, who wasn鈥檛 involved in the research. 鈥淭hese results 鈥� showing that patients can breathe more easily and feel better in general 鈥� are promising. Laughter therapy is simple and low-cost, meaning it could be used by anyone, anywhere in the world. We look forward to further research in this area.鈥�

The team hopes to expand its work with international collaborators.

Running with a pram or stroller might make parents less susceptible to ankle pain and injuries to their calf muscles, foot arches and Achilles tendons. A survey of parents suggests there is a 37 per cent drop in injury risk with pram use. This may be partly due to changes in vertical forces 鈥� how much force our legs absorb with each step 鈥� when pushing a child.

鈥淵ou get a little bit of a walker effect where you鈥檙e leaning and putting some weight on the stroller,鈥� says at Pennsylvania State University, who ran with a pram after the births of her two children. 鈥淭hat led me to wonder, you know, is this actually protective?鈥�

Previous research suggests that people running with a pram tend to have . They also lean forward more, with . Last year, Altman Singles and her colleagues found there is a when running with a pram, but whether this affects injury risk was unclear.

To learn more, Altman Singles and her team analysed self-reported running and injury data from 196 parents who used any kind of pram on at least some of their runs while their children were younger than 3 years old. These individuals were compared against another 53 mothers or fathers who ran when their children were the same age, but without prams. All the participants had some running experience before becoming parents.

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The two groups of parents covered similar total distances and were relatively well matched in terms of factors like age, height and weight. But there were many more women than men in both groups, particularly the pram one.

Overall, 30 per cent of the non-pram runners reported having had running-related injuries, compared with 19 per cent of the pram runners. These included a higher incidence of ankle pain, calf muscle injury, plantar fasciitis (heel pain that occurs when the thick band of tissue on the bottom of the foot becomes irritated or inflamed) and Achilles tendinitis (injury of the Achilles tendon).

Why slow running could be even more beneficial than running fast

The slow-running movement, in which people meet for unhurried jogs, is booming 鈥� but don鈥檛 be fooled into thinking that if there鈥檚 no pain, there鈥檚 no gain

鈥淕enerally, stroller running involves rapid steps with short stride lengths,鈥� says at Seattle Pacific University. 鈥淎lthough this can increase metabolic cost, it can also decrease the force production at each foot strike, which might explain some of these injury reductions.鈥�

Wall-Scheffler says we should see this paper as a 鈥済reat start鈥� to understanding an important topic. However, future work should include a more balanced mix of men and women, she says. For instance, oestrogen and progesterone , which could affect a woman鈥檚 injury risk.

Future studies should also collect injury-related data more regularly over time and could even investigate the effects of different pram-pushing styles, such as using one or two hands, says Wall-Scheffler.

Extraordinary underwater videos have captured orcas making sunfish explode by ramming them at high speed. The behaviour may help juvenile orcas feed by breaking the prey into many small pieces, but it also appears that the orcas may enjoy playing with their food.

鈥淚t鈥檚 a hunting tactic, but that involves a play game in the process,鈥� says , an independent marine biologist in Mexico. 鈥淭here鈥檚 鈥榟igh-octane鈥� adrenaline and a lot of other hormones rushing through their bodies, so, of course, there鈥檚 got to be some sort of excitement.鈥�

Sharp-tail sunfish (Masturus lanceolatus) are among the largest bony fish, weighing up to 2000 kilograms. Higuera had already seen groups of orcas (Orcinus orca) attacking sunfish in the Gulf of California, ripping off parts of their flesh and tossing them around to each other in a playful manner. In the past few years, he had even witnessed them .

Then, in July 2024, his colleague at US non-profit organisation Beneath the Waves caught an explosive interaction on her GoPro camera while diving in the Gulf of California. An adult female orca held onto a dead sunfish while an adult male orca swam upside down towards it at full speed. The female released the sunfish at the last second, and the male hit it with so much force that the fish burst into a flurry of small fragments.

A year later, tourist Hector Franz shot a similar underwater scene in the same bay. This time, an adult female rammed right-side-up into a sharp-tail sunfish held in place by another adult female, popping it into pieces. Combined, the two events mark the first time scientists have seen such behaviour by orcas, say Higuera, Ayres and their colleagues.

Sunfish have 鈥渁n incredibly dense, rubbery, collagenous鈥� outer layer that鈥檚 harder to bite through, so bursting them open could be an effective way to feed on them, says Higuera.

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鈥淭he explosive fragmentation seemed mostly to be of the stiff gelatinous capsule that makes up a high percentage 鈥� more than 80 per cent in large fish 鈥� of the body mass of the sunfish,鈥� says at University College Cork in Ireland. 鈥淚 suspect that calves cannot achieve enough force to do this, as their mass is too low. But they can exploit a cloud of objects that contain tasty morsels.鈥�

Earlier sightings without full footage indicated that the entire pod was involved in a strategic attack process leading up to the rammings, says Higuera. The findings point to advanced cooperative hunting skills and even planning 鈥� especially adapting their techniques for different kinds of prey, he says.

Higuera suspects that popping the sunfish offered a learning experience for the calves, while providing them with bite-sized snacks. Simultaneously, these events could also reinforce social bonds through 鈥減lay鈥� and social learning in this highly intelligent species, he adds.

at the University of Tennessee in Knoxville says it is possible the orcas were having some fun in demolishing the fish, but play wouldn鈥檛 be the only goal, as there is clearly cooperative foraging going on as well.

鈥淥ne of the fascinating things about play is that it can be a driver of behavioural innovation,鈥� says at the University of Pisa, Italy. 鈥淚t鈥檚 possible that a behaviour like this may have originated in a playful context and later acquired a feeding function, or vice versa. At this stage, we simply don鈥檛 know.鈥�