A new cat species has been scientifically described 鈥� the diminutive, spotted tilcayo from Bolivia.

Several species of small cat in the Leopardus genus live in South America, including the ocelot, margay, kodkod, Geoffroy鈥檚 cat and the tiger cat or oncilla. The similar appearance of these nocturnal and hard-to-spot cats has made separating them into distinct species difficult.

This is particularly true of tiger cats, which are about the size of a house cat, and are found in Costa Rica in Central America, and across a vast swathe of South America including Bolivia, Brazil, Venezuela, Colombia, Ecuador and Peru. Historically, there have been many local and scientific names for them, but they all got subsumed into a single species, Leopardus tigrinus.

Genetic studies have since divided the species into four, resurrecting three of the species names that scientists once used before they were all lumped together under the name L. tigrinus. This process saw the official recognition of the in 2013, in 2017 and the in 2024.

Now, at the Pontifical Catholic University of Rio Grande do Sul (PUCRS) in Porto Alegre, Brazil, and his colleagues have analysed the complete genomes of 38 individuals from the Leopardus genus, including 26 tiger cats from across their known range.

The genomics revealed a fifth distinct species living in the Bolivian Yungas forests on the east slopes of the Andes mountains. The researchers describe it under a completely new name: Leopardus tilcayo, naming it after the local term used for this cat.

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鈥淲e鈥檝e discovered a new species of cat that had not been scientifically named before,鈥� says Eizirik, adding that this is the first time this has happened for a century.

鈥淭here are more cat species. Who can鈥檛 love that?鈥� says at the University of California, Davis. 鈥淭hey鈥檙e hard to find and see, so it鈥檚 not surprising that some of the early taxonomy needs to be modified now we have more data.鈥�

L. tilcayo has a combined head and body length of between about 42 and 50 centimetres and weighs between 1.5 and 2 kilograms. The genomes revealed that it diverged from the lineage containing L. tigrinus and L. pardinoides nearly 1.4 million years ago.

Origin story of domestic cats rewritten by genetic analysis

Domestic cats originated in North Africa and spread to Europe in the past 2000 years, according to DNA evidence, while in China a different species of cat lived alongside people much earlier

Telling the new species apart visually is not easy. 鈥淭he five tiger cat species are all cryptic species. They鈥檙e morphologically very similar,鈥� says team member at University of Antwerp in Belgium.

The researchers also found that in the Peruvian Yungas forests, on the west side of the Andes, there is a distinct group of cats in the L. tigrinus lineage that they describe as a novel subspecies, L. tigrinus antisuyo.

There are so many barriers in South America that can geographically isolate animal populations from each other, including mountains and rivers, that more cat species may be waiting to be found, says Lyons. 鈥淚t鈥檇 be rather cool if we could find another species out there.鈥�

L. tigrinus is by the IUCN Red List, but the new species and subspecies will have to be evaluated and protected as distinct units, says Eizirik, especially as the forests they live in are shrinking as agriculture expands.

Wild adult chimpanzees have been seen passing tools to youngsters to help them learn and then coaching them, supporting the idea that teaching helps immature chimps acquire technological skills.

鈥淭o actually catch it on film is important and was very surprising for us,鈥� says at the University of Barcelona, Spain.

Chimpanzees are known to make and use a variety of tools, from leaf or moss sponges that soak up water to sticks used to fish for or , and even crafting simple spears for hunting. But how chimpanzees learn such skills is debated.

It is clear that the knowledge does get passed on. For example, one study showed an increase in the number of chimps in Uganda using moss as a sponge to soak up water from a pond. Work with captive chimps has also shown that the animals can pass on knowledge to others. The big question is whether individuals copy behaviour after observation, actively teach each other or independently come up with the same solutions to a task.

To see if they could answer that, Hernandez-Aguilar and her colleagues analysed 15 hours of footage from camera traps at the 鈥檚 biological station in Dindefelo, Senegal, taken between 2017 and 2025. The cameras were placed near 14 sites in the area where wild western chimpanzees (Pan troglodytes verus) had previously been recorded using tools, including fishing for algae, army ants and termites.

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In total, the camera traps recorded聽33 instances of tool transfer from one chimp to another: 19 when they were dipping for ants to eat, 10 during fishing for algae and four when fishing for termites. Generally, a chimp handed the key object to a close relative, and in 30 per cent of cases, this was from a mother to her offspring.

In one video, a mother, Soukki, inserted a dipping stick into an ant nest, then grabbed her baby daughter, Sa茂sa茂, and led her to the tool. Sa茂sa茂 pulled the stick out and ate the ants clinging to it.

鈥淲e found support for the idea that tool transfers are a form of teaching that experienced chimpanzees may use to facilitate the learning of young individuals,鈥� says team member , also at the University of Barcelona.

The team also gathered 30 minutes of footage from cameras at 11 sites where chimpanzees to crack them open. This is considered proto-tool use rather than tool use, because the stones are being used as an anvil rather than being directly held and manipulated.

In an example of this, a mother called F茅r茅 collected three baobab fruits and placed them near her infant son Fotti. A juvenile male 鈥� probably an older sibling 鈥� picked up a fruit and pounded it against some rocks while Fotti watched, then guided Fotti鈥檚 hand to a fruit. Fotti had a go himself, eventually managing to open up a fruit. 聽

The videos support the idea that other social mechanisms such as observation and supervised practice help youngsters learn to use tools, says S谩nchez-Meg铆as.

鈥淭eaching events are quite rare and difficult to study because only so many learning attempts are needed until an individual learns a behaviour,鈥� says at the Max Planck Institute of Animal Behavior in Germany. 鈥淪howing across many forms of tool use that these tool transfers are indicative of a very simple form of teaching is very cool and nice.鈥�

During the observed interactions, the researchers noted that the teacher was forgoing food for the learning youngster鈥檚 benefit.

鈥淭his is an important observation because it fits the criteria for teaching used in animal behaviour research 鈥� that the behaviour benefits the pupil鈥檚 opportunities to learn, and is done despite having a cost to the teacher,鈥� says at the University of St Andrews, UK.

A genetically modified pig鈥檚 kidney kept a man with organ failure off dialysis for nine months while he waited for a suitable human donor鈥檚 kidney to become available. This suggests pig kidneys could act as a temporary measure amid lengthy organ waiting lists, but they may also work as a permanent replacement one day.

鈥淚 think it鈥檚 incredible in terms of the science behind it and what they鈥檝e achieved,鈥� says at Imperial College London, who wasn鈥檛 involved in the work.

For people with severe kidney disease, where these organs are failing and dialysis is needed, a kidney transplant provides the best chance of survival and better quality of life. However, demand for donor organs exceeds supply.

One possible solution is xenotransplantation, the transfer of organs from other animals into humans. In January 2022, a pig heart was transplanted into a person for the first time, but the recipient died several months later, possibly due to the presence of a pig virus. A pig liver transplant also occurred last year.

A pig鈥檚 kidney was transplanted into a living person for the first time in 2024. The recipient, Richard Slayman, aged 62, died 52 days later from cardiac-related causes. In the latest development, Tim Andrews, a 66-year-old man with end-stage kidney failure, opted to receive a kidney from a pig to avoid dialysis while he waited for a suitable human organ.

at Mass General Brigham hospital in Boston and his colleagues transplanted the kidney, which came from a Yucatan miniature pig, into Andrews in January 2025. The organ had been genetically modified to improve compatibility with the human immune system, such as by removing some sugars that we produce antibodies against and adding seven human genes.

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The transplant was initially a success, and Andrews 鈥� who also received immunosuppression drugs to stop his body rejecting the organ 鈥� came off dialysis and resumed normal life. However, after about six months, he was admitted to hospital with a methicillin-resistant Staphylococcus aureus (MRSA) infection, which most antibiotics can鈥檛 kill. 聽

Riella and his colleagues reduced the immunosuppression drugs Andrews was on, but then damage started to develop in the kidney鈥檚 blood vessels. This progressed to organ failure, and the kidney was removed a record 271 days after transplantation. 鈥淗e had a kidney that lasted nine months, which is mind-blowing,鈥� says Riella.

Andrews went back onto dialysis for about three months, before finally receiving a suitable human kidney in January 2026. This marks the first time a pig kidney has been used as a temporary bridge to a human transplant.

鈥淪uch transplants may allow patients to avoid going through dialysis, which is so important because it causes so much wear and tear to the body,鈥� says Riella. 鈥淗opefully, maybe 15 years from now, pig kidneys will compete with a human kidney transplant, but you鈥檙e not there yet.鈥�

2024 saw the first living people to receive pig kidney transplants

Three people in the US received a genetically modified pig kidney in 2024, marking another step towards animal-to-human organ transplants becoming routine

The procedure is experimental, and Riella couldn鈥檛 give an estimate of how much it might cost. But in the US, there are about 600,000 people on dialysis, which can cost about $100,000 a year per individual, he says.

Riella says the team has now done five such transplants and two more case reports will be published this year, including one of a person who has already beaten Andrews鈥檚 record of nine months with a functioning pig kidney.

鈥淚 think these will be carried out more widely in the future, but it鈥檒l be a little while,鈥� says Willicombe, largely due to their probable high cost. 女生小视频s should also continue researching artificial kidneys, as well as ways to regenerate damaged organs and optimise donated ones, she says.

Some of the benefits of a rigorous workout might one day be achievable without any physical exertion. A study in mice shows that injecting muscle cells beneath the skin creates a patch of these cells that continuously contracts, delivering some of the benefits of exercise around the clock. While this should never replace physical activity, it may be helpful for people who are unable to exercise, such as those in hospital.

Initially, at the Beijing Institute for Stem Cell and Regenerative Medicine in China and his colleagues injected muscle cells into mice with the aim of increasing their muscle mass, but this had an unexpected result. 鈥淭his thing was contracting under the skin continuously, and we thought, 鈥楾his thing is like non-stop exercise鈥�,鈥� says Ng.

They started by taking samples of muscle stem cells from live mice, which they cultured until the cells differentiated into mature, contractile muscle cells known as myocytes. They then injected these just beneath the skin on the backs of the same mice. 鈥淭he original intention was to increase muscle mass by injecting muscle cells,鈥� says Ng.

With an injection of about 6 million myocytes, a patch of cells formed, creating its own network of mini blood vessels. This then began to pulse continuously, even when the mice were asleep.

Various experiments showed the patches had widespread effects around the mice鈥檚 bodies. For instance, the mice given the muscle patches had a higher whole-body muscle mass and better immune function compared with those that got a sham injection. All the mice were free to move around their cages as normal during the study.

What鈥檚 more, in mice that were 18 months old (roughly equivalent to a person in their late 50s or 60s) and those fed to induce obesity, the patches improved muscle mass, bone density, physical strength and endurance.

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These mice also showed reversal in signs of liver damage, as well as reduced inflammation and the ability to navigate a maze faster. 鈥淪o, it also has effects on its brain,鈥� says Ng. 鈥淭his is known from exercise, but here, we鈥檙e seeing it from a small muscle graft.鈥�

The patch鈥檚 wide-ranging effects may be due to it mimicking how . 鈥淲hat I find particularly interesting is that the effects appear to go beyond the graft itself,鈥� says at Duke-NUS Medical School in Singapore. 鈥淭he study suggests that the contracting muscle can act as an endocrine organ, with changes in circulating factors that may contribute to effects in other tissues.鈥�

Imaging showed that the muscle patches survived for at least 81 days, when the researchers stopped taking measurements, but Ng says that follow-up work indicates they are still stable after six months. 鈥淪o far, there鈥檚 no limit to its lifespan as far as I can tell,鈥� he says. There also seems to be very little reduction in volume over time and no evidence of tumour growth, which can be a risk after implanting stem cells.

Just 1 minute of vigorous exercise a day could add years to your life

People who do several very short bouts of strenuous activity each day are much less likely to die in the next few years than those who do no exercise at all

Ng hopes the patch could help people with medical conditions that stop them from exercising. The researchers are talking to several hospitals about starting clinical trials in people with limited mobility, which could begin within a year, he says. 鈥淲e always say we should exercise to keep muscle mass, but the folks that need exercise the most are actually the ones least likely to be able to exercise,鈥� he says.

鈥淭he idea of mimicking exercise for people who can鈥檛 exercise is amazing,鈥� says at King鈥檚 College London, but he questions how comfortable a continuously contracting graft like this would be.

Tang stresses that the patch should be thought of as mimicking some aspects of exercise, rather than replacing it. 鈥淓xercise has many other effects 鈥� including cardiovascular, neuromuscular, mechanical and bone-loading effects 鈥� that a small subcutaneous muscle graft cannot fully reproduce,鈥� he says.

Researchers have identified specific groups of neurons in the brains of mice that are activated after the rodents have been awake for a long time, driving them to get some sleep.听If a similar system exists in humans, it could be targeted to help improve treatments for some sleep disorders.

Inside the brain, several neural circuits聽, including neurons in the hypothalamus that聽.听

One or more of these circuits might be involved in why it is that, the longer we are awake, the more irresistible the urge to close our eyes becomes. But what actually drives this impulse has long been a mystery.

To find out,聽聽at the University of Basel in Switzerland and his colleagues have compared brain activation patterns in mice during normal sleep-wake cycles, sleep deprivation and recovery sleep. They did this by tracing how much protein is produced in cells by a gene called听贵辞蝉, which is turned on when neurons are in the process of activating.

鈥淲e saw that very specific parts of the brain were correlated with wakefulness,鈥� says Joo. This allowed the researchers to identify areas in which activity correlated with time spent awake.听

Within one of these regions, the median raphe nucleus, they found two distinct neuronal populations that were increasingly activated the longer the animals stayed awake and that got quieter again after sleep started. These populations are the GABAergic and serotonergic neurons, so named because the chemical messenger molecules they respond to are gamma-aminobutyric acid (GABA) and serotonin, respectively.

鈥淭his is an outstanding study. The whole-brain Fos mapping is a real tour de force,鈥� says聽聽at the University of Wisconsin鈥揗adison.

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To see whether these neuronal populations became more active simply because the mice had been awake for a long time or whether they do something more, Joo and his colleagues then used viruses to deliver a genetic package to the neurons to either activate or inhibit their action.

When both sets of neurons were artificially activated, the mice slept for twice or three times as long as control mice and spent more time in non-REM slow-wave sleep 鈥� in a way that resembles the deeper recovery sleep humans have after we have been up for a long time.听

鈥淣ot only does it increase the amount of time the animal spends sleeping, but it also increases the quality of the sleep,鈥� says Joo.

When the neurons were inhibited, the mice slept about 70 per cent less than control mice 鈥� spending around 6.5 extra hours awake a day 鈥� without showing more of the anxiety-like behaviours that usually come with sleep deprivation for mice. However, the lack of sleep was lethal in about 17 per cent of the mice.听

The strong effect of activating and inhibiting the neurons means they don鈥檛 just signal that an animal has been awake, says team member聽, also at the University of Basel. 鈥淭hey are crucial to promote sleep, and may be key components of the neural circuitry that generates sleep drive.鈥澛�

The study 鈥渁dds to a growing body of work showing that there are distinct sleep circuits that are activated by wakefulness, yet promote sleep鈥�, says聽聽at Johns Hopkins University in Maryland, whose research has shown that neurons in a brain region called the thalamic nucleus reuniens聽track the gap between how much sleep we need and how much we actually get.

It isn鈥檛 known if the same sleep-driving neuron populations exist in humans, but if they do, the findings could open doors to new therapies for some sleep-related conditions 鈥� once we know how the cells are communicating with other brain regions, say the researchers.听

Projections from these neurons in the median raphe nucleus , and these areas are known to work together to control the sleep-wake cycle.

鈥淭he effect of this major neuronal path on sleep is very strong, but, as we have learned since we started manipulating neuronal circuits, each path provides nuances. The brain has many ways to wake up and fall asleep,鈥� says聽 at Stanford University in California.

For example, there are hints from experiments in fruit flies that聽mitochondria, which power cells, in the brain may play a crucial role in the onset of sleep.听

Ancient Egyptian princesses were probably trained in using bows and daggers and put themselves at risk of serious injury. Rediscovering mummies from about 3800 years ago has revealed that some of these women had enlarged bones in their arms and bowing of the bones in their palms, which suggests they were active users of the weapons they were often buried with.

鈥淭hey carried their bows and daggers into the afterlife not just as ornaments, but as testaments to the active, resilient and powerful lives they led,鈥� says at Beni-Suef University in Egypt.

Weapons have been found throughout history. But there has been much debate about whether this was symbolic or meant the women used them.

Now, Hashesh and her colleagues have studied six royal mummies 鈥� five female 鈥� found at the Dahshur complex of pyramids and tombs from Egypt鈥檚 Middle Kingdom between about 1850 and 1700 BC. The mummies, some of which were found with bows and arrows alongside them, were excavated in the 1890s, and were rediscovered in the Egyptian Museum in Cairo during a curation project in 2020. 聽

The team has analysed the bones to learn about the lives of these royal individuals, four of whom are thought to be daughters of the pharaoh Amenemhat II.

A key finding was that Princess Ita 鈥� who had an elaborate gold and lapis lazuli dagger in her burial assemblage and was aged between 28 and 34 when she died 鈥� would have had very strong connections between the bones in her forearm and strong hand muscles. This implies the habitual gripping of weapons like daggers or maces, says Hashesh.

Princesses Noub-Hotep (aged between 40 and 44) and Itaweret (aged 20 to 34) both showed enlargement of the radius bone in the forearm, which could be an adaptation to . The former princess, who was buried alongside arrows, also had bowing of the second right metacarpal bone in the palm and strengthened attachments of finger muscles. These hint at the sustained mechanical load required to hold a bow and are indicative of 鈥渁rcher鈥檚 grip鈥�.

鈥淚 imagine the lives of princesses like Noub-Hotep and Ita were far from the sedentary, purely decorative existence we often associate with ancient royalty,鈥� says Hashesh. 鈥淭o develop the archer鈥檚 grip and the structural bowing of the hand bones observed in Noub-Hotep, they must have begun training in archery and martial arts from a young age.鈥�

at Griffith University in Australia says this study gives us real insight into these princesses鈥� lives. 鈥淩oyal women were not simply sitting around a palace or following their menfolk around, but living active and skilled lives. They were trained in very practical martial and hunting arts, just as we imagine their fathers and brothers were,鈥� she says.

The bones also revealed that injuries were common. For example, Princess Itaweret survived broken ribs and foot fractures, which Hashesh says were probably caused by accidents or hard blows.

鈥淭his tells us that they were out in the world, perhaps engaged in high-impact activities where falls and blows were a real danger,鈥� she says. When injured, their status gave them access to surgeons capable of setting bones so well that they healed without infection or misalignment, she says.

But at the University of Southampton, UK, says that other activities could result in similar alterations to arm and hand bones, such as frequent juggling or using a scythe. 鈥淚f we were to find a tennis player buried with a club, we cannot simply argue that this [similar] bony change was a result of clubbing people,鈥� she says.