Scientists have grown tooth-like structures using a combination of pig and human cells, marking a step toward potential alternatives to dental implants, researchers at Tufts University School of Dental Medicine reported.

The team, led by Pamela Yelick and Weibo Zhang, cultivated the structures by seeding cells into pig tooth scaffolds and implanting them in mini pigs' jaws. After two months, the bioengineered teeth developed hard tissue layers similar to natural teeth, including dentin and cementum. While not yet fully formed teeth, the structures could eventually lead to living replacements for lost teeth, addressing limitations of current titanium implants.

A new study reveals that two Grand Canyon-sized valleys were formed in less than 10 minutes by "floods of rocks traveling as fast as bullets," reports Space.com. From the report: Scientists analyzed the lunar canyons, named Vallis Schrodinger and Vallis Planck, to find that these huge valleys measure 167 miles long (270 kilometers) and nearly 1.7 miles (2.7 km) deep, and 174 miles long (280 km) and nearly 2.2 miles deep (3.5 km), respectively. In comparison, the Grand Canyon is 277 miles long (446 km) and is, at most, about 1.2 miles deep (1.9 km), the researchers noted. [...] This pair of lunar canyons represents two of many valleys radiating out from Schrodinger basin, a crater about 200 miles wide (320 km) that was blasted out of the lunar crust by a cosmic impact about 3.81 billion years ago. This structure is located in the outer margin of the moon's largest and oldest remaining impact crater, the South Pole-Aitken basin, which measures about 1,490 miles wide (2,400 km) and dates about 4.2 billion to 4.3 billion years old.

[...] The scientists estimate that rocky debris flew out from the impact at speeds between 2,125 to 2,860 miles per hour (3,420 to 4,600 km/h). In comparison, a bullet from a 9mm Luger handgun might fly at speeds of about 1,360 mph (2,200 km/h). The researchers suggest the energy needed to create both of these canyons would have been more than 130 times the energy in the current global inventory of nuclear weapons. "The lunar canyons we describe are produced by streams of rock, whereas the Grand Canyon was produced by a river of water," [said David Kring, a geologist at the Lunar and Planetary Institute of the Universities Space Research Association]. "The streams of rock were far more energetic than the river of water, which is why the lunar canyons were produced in minutes and the Grand Canyon produced over millions of years." The findings have been published in the journal Nature.

Scientists are making significant advances in developing artificial blood substitutes, with two promising approaches emerging in 2025, the New Yorker reports. At the University of Maryland School of Medicine's Center for Blood Oxygen Transport and Hemostasis, researchers are testing ErythroMer, a synthetic nanoparticle that mimics red blood cells' oxygen-carrying capabilities. Simultaneously, the UK's National Health Service is conducting the first human trials of lab-grown blood cells.

These developments address critical blood shortages - of the 38% of Americans eligible to donate, less than 3% do so regularly. Traditional donated blood also has significant limitations: platelets last only 5 days, red blood cells 42 days, and all require careful refrigeration and blood-type matching. DARPA awarded $46 million in early 2023 to develop ErythroMer, seeing potential for battlefield medicine where traditional blood storage isn't feasible.

The synthetic blood can be stored as a powder and reconstituted when needed. There are still a lot of challenges, the report adds. The lab-grown blood currently costs about $75,000 per syringe compared to around $200 for a pint of donated blood, and production is limited to small quantities.

An anonymous reader quotes a report from The Guardian: The pace of global heating has been significantly underestimated, according to renowned climate scientist Prof James Hansen, who said the international 2C target is "dead." A new analysis by Hansen and colleagues concludes that both the impact of recent cuts in sun-blocking shipping pollution, which has raised temperatures, and the sensitivity of the climate to increasing fossil fuels emissions are greater than thought. The group's results are at the high end of estimates from mainstream climate science but cannot be ruled out, independent experts said. If correct, they mean even worse extreme weather will come sooner and there is a greater risk of passing global tipping points, such as the collapse of the critical Atlantic ocean currents.

Hansen, at Columbia University in the US, sounded the alarm to the general public about climate breakdown in testimony he gave to a UN congressional committee in 1988. "The Intergovernmental Panel on Climate Change (IPPC) defined a scenario which gives a 50% chance to keep warming under 2C -- that scenario is now impossible," he said. "The 2C target is dead, because the global energy use is rising, and it will continue to rise." The new analysis said global heating is likely to reach 2C by 2045, unless solar geoengineering is deployed. [...] In the new study, published in the journal Environment: Science and Policy for Sustainable Development, Hansen's team said: "Failure to be realistic in climate assessment and failure to call out the fecklessness of current policies to stem global warming is not helpful to young people."

[...] Hansen said the point of no return could be avoided, based on the growing conviction of young people that they should follow the science. He called for a carbon fee and dividend policy, where all fossil fuels are taxed and the revenue returned to the public. "The basic problem is that the waste products of fossil fuels are still dumped in the air free of charge," he said. He also backed the rapid development of nuclear power. Hansen also supported research on cooling the Earth using controversial geoengineering techniques to block sunlight, which he prefers to call "purposeful global cooling." He said: "We do not recommend implementing climate interventions, but we suggest that young people not be prohibited from having knowledge of the potential and limitations of purposeful global cooling in their toolbox." Political change is needed to achieve all these measures, Hansen said: "Special interests have assumed far too much power in our political systems. In democratic countries the power should be with the voter, not with the people who have the money. That requires fixing some of our democracies, including the US."

Scientists have demonstrated control over a newly theorized type of magnetism, known as altermagnetism, by manipulating nanoscale magnetic whirlpools in an ultra-thin wafer of manganese telluride. "Our experimental work has provided a bridge between theoretical concepts and real-life realization, which hopefully illuminates a path to developing altermagnetic materials for practical applications," says University of Nottingham physicist Oliver Amin, who led the research with PhD student Alfred Dal Din. From the report: Using a device that accelerates electrons to blinding speeds, a team led by researchers from the University of Nottingham showered an ultra-thin wafer of manganese telluride with X-rays of different polarizations, revealing changes on a nanometer scale reflecting magnetic activity unlike anything seen before. [...] More recently, a third configuration of particles in ferromagnetic materials was theorized.

In what's referred to as altermagnetism, particles are arranged in a canceling fashion like antiferromagnetism, yet rotated just enough to allow for confined forces on a nanoscale -- not enough to pin a grocery list to your freezer, but with discrete properties that engineers are keen to manipulate into storing data or channeling energy. "Altermagnets consist of magnetic moments that point antiparallel to their neighbors," explains University of Nottingham physicist Peter Wadley. "However, each part of the crystal hosting these tiny moments is rotated with respect to its neighbors. This is like antiferromagnetism with a twist! But this subtle difference has huge ramifications."

Experiments have since confirmed the existence of this in-between 'alter' magnetism. However, none had directly demonstrated it was possible to manipulate its tiny magnetic vortices in ways that might prove useful. Wadley and his colleagues demonstrated that a sheet of manganese telluride just a few nanometers thick could be distorted in ways that intentionally created distinct magnetic whirlpools on the wafer's surface. "Our experimental work has provided a bridge between theoretical concepts and real-life realization, which hopefully illuminates a path to developing altermagnetic materials for practical applications," says University of Nottingham physicist Oliver Amin. This research was published in the journal Nature.

An anonymous reader quotes a report from The Guardian: Advanced artificial intelligence is to revolutionize fundamental physics and could open a window on to the fate of the universe, according to Cern's next director general. Prof Mark Thomson, the British physicist who will assume leadership of Cern on 1 January 2026, says machine learning is paving the way for advances in particle physics that promise to be comparable to the AI-powered prediction of protein structures that earned Google DeepMind scientists a Nobel prize in October. At the Large Hadron Collider (LHC), he said, similar strategies are being used to detect incredibly rare events that hold the key to how particles came to acquire mass in the first moments after the big bang and whether our universe could be teetering on the brink of a catastrophic collapse.

"These are not incremental improvements," Thomson said. "These are very, very, very big improvements people are making by adopting really advanced techniques." "It's going to be quite transformative for our field," he added. "It's complex data, just like protein folding -- that's an incredibly complex problem -- so if you use an incredibly complex technique, like AI, you're going to win."

The intervention comes as Cern's council is making the case for the Future Circular Collider, which at 90km circumference would dwarf the LHC. Some are skeptical given the lack of blockbuster results at the LHC since the landmark discovery of the Higgs boson in 2012 and Germany has described the $17 billion proposal as unaffordable. But Thomson said AI has provided fresh impetus to the hunt for new physics at the subatomic scale -- and that major discoveries could occur after 2030 when a major upgrade will boost the LHC's beam intensity by a factor of ten. This will allow unprecedented observations of the Higgs boson, nicknamed the God particle, that grants mass to other particles and binds the universe together. Thomson is now confident that the LHC can measure Higgs boson self-coupling, a key factor in understanding how particles gained mass after the Big Bang and whether the Higgs field is in a stable state or could undergo a future transition. According to Thomson: "It's a very deep fundamental property of the universe, one we don't fully understand. If we saw the Higgs self-coupling being different from our current theory, that that would be another massive, massive discovery. And you don't know until you've made the measurement."

The report also notes how AI is being used in "every aspect of the LHC operation." Dr Katharine Leney, who works on the LHC's Atlas experiment, said: "When the LHC is colliding protons, it's making around 40m collisions a second and we have to make a decision within a microsecond ... which events are something interesting that we want to keep and which to throw away. We're already now doing better with the data that we've collected than we thought we'd be able to do with 20 times more data ten years ago. So we've advanced by 20 years at least. A huge part of this has been down to AI."

Generative AI is also being used to look for and even produce dark matter via the LHC. "You can start to ask more complex, open-ended questions," said Thomson. "Rather than searching for a particular signature, you ask the question: 'Is there something unexpected in this data?'"

A study found that bonobos can recognize when someone lacks knowledge they possess and take action to help, demonstrating a basic form of theory of mind. This suggests that the ability to understand others' perspectives is evolutionarily older than previously thought and may have existed in our common ancestors to enhance cooperation and coordination. New Scientist reports: [W]e have been missing clear evidence from controlled settings that primates can track a perspective that differs from their own and then act upon it, says Luke Townrow at Johns Hopkins University in Maryland. To investigate this, Townrow and Christopher Krupenye, also at Johns Hopkins University, tested if three male bonobos at the Ape Initiative research centre in Iowa could identify ignorance in someone they were trying to cooperate with, and then gesture to them to help solve the task. On a table between the bonobo and an experimenter were three upturned plastic cups. A second researcher placed a barrier between the experimenter and the cups, then hid a treat, like a juicy grape, under one of them.

In one version of the experiment, the "knowledge condition," a window in the barrier allowed the experimenter to watch where the treat was placed. In the "ignorance condition," their view was completely blocked. If the experimenter found the food, they would give it to the bonobo, providing a motivation for the apes to share what they knew. Townrow and Krupenye looked at whether the ape pointed at the cup, and how quickly they pointed, after the barrier had been removed over 24 trials for each condition. They found that, on average, the bonobos took 1.5 seconds less time to point and pointed in approximately 20 per cent more trials in the ignorance condition. "This shows that they can actually take action when they realize that somebody has a different perspective from their own," says Krupenye. It appears that bonobos understand features of what others are thinking that researchers have historically assumed they didn't comprehend, he adds. The findings have been published in the journal PNAS.

A century after quantum mechanics revolutionized physics, scientists still cannot agree on how the theory fundamentally works, despite its tremendous success in explaining natural phenomena and enabling modern technologies. The theory's central puzzle remains unresolved: the way quantum systems are described mathematically differs from what scientists observe when measuring them.

This has led to competing interpretations about whether quantum states represent physical reality or are merely tools for calculating probabilities. As researchers debate these foundational questions, quantum mechanics has enabled breakthroughs in particle physics, chemistry, and computing. It accurately predicts phenomena from the behavior of atoms to the properties of the Higgs boson, and underlies technologies like quantum computers and ultra-precise measurement devices. The field's inability to reach consensus on its foundations hasn't hindered its practical applications. Scientists continue to develop new quantum technologies even as they grapple with deep questions about measurement, locality, and the nature of reality that have persisted since Einstein and Bohr's famous debates in the 1920s and 1930s.

The exponential rise in microplastic pollution over the past 50 years may be reflected in increasing contamination in human brains, according to a new study. From a report: It found a rising trend in micro- and nanoplastics in brain tissue from dozens of postmortems carried out between 1997 and 2024. The researchers also found the tiny particles in liver and kidney samples. The human body is widely contaminated by microplastics. They have also been found in blood, semen, breast milk, placentas and bone marrow. The impact on human health is largely unknown, but they have been linked to strokes and heart attacks.

The scientists also found that the concentration of microplastics was about six times higher in brain samples from people who had dementia. However, the damage dementia causes in the brain would be expected to increase concentrations, the researchers said, meaning no causal link should be assumed. "Given the exponentially rising environmental presence of micro- and nanoplastics, this data compels a much larger effort to understand whether they have a role in neurological disorders or other human health effects," said the researchers, who were led by Prof Matthew Campen at the University of New Mexico in the US.

Spirit Aerosystems builds aircraft components, including fuselages and flight deck sections for Boeing, according to Wikipedia. But now Boeing is set to acquire Spirit AeroSystems.

The aviation blog called Aviation Source News says the price tag was $4.7 billion, and opines that Boeing's move signals "a renewed focus on quality and supply chain stability" as Boeing "addresses lingering concerns surrounding its 737 program." Spirit's recent struggles with quality control and production delays have had a fallout effect for Boeing... By integrating Spirit's operations, Boeing can implement more stringent oversight and ensure consistent manufacturing processes. This move is a direct response to past quality lapses that have plagued the company and damaged its reputation. Beyond quality control, the acquisition also offers Boeing greater control over its supply chain. By bringing a key supplier in-house, Boeing can streamline production, improve coordination, and reduce the risk of future disruptions...

Spirit AeroSystems also supplies parts to Airbus, Boeing's main competitor. To address this, a separate agreement is being negotiated for Airbus to acquire Spirit's Airbus-related business. This strategic move ensures that Airbus maintains control over its own supply chain and prevents Boeing from gaining undue influence over its competitor's production.
Meanwhile, the vice president leading Boeing's Starliner spacecraft unit "has left his role in the program and been replaced by the company's International Space Station program manager, John Mulholland," Reuters reports, citing a Boeing spokesperson. In its first test mission last summer flying astronauts, Starliner was forced by NASA to leave its crew aboard the ISS and return empty in September over problems with its propulsion system. A panel of senior NASA officials in August had voted to have a Crew Dragon capsule from Elon Musk's SpaceX bring them back instead, deeming Starliner too risky for the astronauts.

Paul Hill, a veteran NASA flight director and member of the agency's Aerospace Safety Advisory Panel, said during a quarterly panel meeting on Thursday that NASA and Boeing continue to investigate Starliner's propulsion system. A Boeing spokesperson said on Thursday that the company and NASA have not yet determined what Starliner's next mission will look like, such as whether it will need to repeat its crewed flight test before receiving NASA certification for routine flights.

An anonymous reader shared this report from the Washington Post: Scientists have found that using seismometers is a new and inexpensive method to detect falling space junk, which can cause damage on impact and carry toxic materials — and may someday turn deadly...

It's not an easy task to track large hunks of falling metal everywhere in the world. Ground-based radar can detect falling objects, but it doesn't cover much of the world or is often classified data, said Ben Fernando [a planetary scientist at Johns Hopkins University who is leading this research]. The other option is through optical instruments, such as doorbell cameras, but the information on the time, size and speed can be limited. Instead, Fernando turned to seismology data. Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris.

Stations located around the world live-stream data, which can be easily downloaded. Seismometers have been used to track meteors in the sky for over a century, but he said this is the first time he's aware of its use for tracking space debris. Fernando first tested the idea to track the controlled reentry of NASA's OSIRIS-REx mission in September 2023, which brought back material from the asteroid Bennu. He set up seismometers along the capsule's path in the landing spot in Utah and measured its sonic boom. "It's a really good way of monitoring what's coming in, how often it's coming in, how big the things hitting the Earth are," said Fernando, who presented his results at the American Geophysical Union conference in December...

"The shockwave deforms the ground around the seismometer," said Fernando. "It also keeps ringing for a lot longer because all of that energy is bouncing around in the soil...." [H]e said an automated system could help detect these objects within moments of it appearing on the stations. In addition to detecting an event, the seismometers can help locate where any debris may have fallen. Tracking debris is important because some space debris can contain toxic materials that can harm the surrounding environment.
The article notes reports of the uncontrolled reentry into Earth's atmosphere of at least 951 objects larger than one square meter from 2010 to 2022.

"On average, objects heavier than 1,000 pounds came down about every 8 days... In fact, the threat of getting hit by uncontrolled orbital reentries has increased by a factor of four from 2010 to 2023, said Luciano Anselmo, who published a study assessing the risk."

Thursday America's FDA "raised concerns about cybersecurity vulnerabilities" in patient monitors from China-based medical device company Contec "that could allow unauthorized individuals to access and potentially manipulate those devices," reports Reuters. The patient monitors could be remotely controlled by unauthorized users or may not function as intended, and the network to which these devices are connected could be compromised, the agency warned. The FDA also said that once these devices are connected to the internet, they can collect patient data, including personally identifiable information and protected health information, and can export this data out of the healthcare delivery environment.

The agency, however, added that it is currently unaware of any cybersecurity incidents, injuries, or deaths related to these identified cybersecurity vulnerabilities.
The FDA's announcement says "The software on the patient monitors includes a backdoor, which may mean that the device or the network to which the device has been connected may have been or could be compromised." And it offers this advice to caregivers and patients: If your health care provider confirms that your device relies on remote monitoring features, unplug the device and stop using it. Talk to your health care provider about finding an alternative patient monitor.

If your device does not rely on remote monitoring features, use only the local monitoring features of the patient monitor. This means unplugging the device's ethernet cable and disabling wireless (that is, WiFi or cellular) capabilities, so that patient vital signs are only observed by a caregiver or health care provider in the physical presence of a patient. If you cannot disable the wireless capabilities, unplug the device and stop using it. Talk to your health care provider about finding an alternative patient monitor.
A detailed report from CISA describes how a research team "created a simulated network, created a fake patient profile, and connected a blood pressure cuff, SpO2 monitor, and ECG monitor peripherals to the patient monitor. Upon startup, the patient monitor successfully connected to the simulated IP address and immediately began streaming patient data..." to an IP address that hard-coded into the backdoor function. "Sensor data from the patient monitor is also transmitted to the IP address in the same manner. If the routine to connect to the hard-coded IP address and begin transmitting patient data is called, it will automatically initialize the eth0 interface in the same manner as the backdoor. This means that even if networking is not enabled on startup, running this routine will enable networking and thereby enable this functionality

Bruce66423 shares a report from the Associated Press: Federal officials on Thursday approved a new type of pain pill designed to eliminate the risks of addiction and overdose associated with opioid medications such as Vicodin and OxyContin. "It's the first new pharmaceutical approach to treating pain in more than 20 years, offering an alternative to opioids and over-the-counter medications such as ibuprofen and acetaminophen. But the medication's modest effectiveness and lengthy development process underscore the challenges of finding new ways to manage pain.

Studies in more than 870 patients with acute pain due to foot and abdominal surgeries showed Vertex's drug provided more relief than a dummy pill but didn't outperform a common opioid-acetaminophen combination pill. "It's not a slam dunk on effectiveness," said Michael Schuh of the Mayo Clinic, a pharmacist and pain medicine expert who was not involved in the research. "But it is a slam dunk in that it's a very different pathway and mechanism of action. So, I think that shows a lot promise." The new drug will carry a list price of $15.50 per pill, making it many times more expensive than comparable opioids, which are often available as generics for $1 or less. [...]

Opioids reduce pain by binding to receptors in the brain that receive nerve signals from different parts of the body. Those chemical interactions also give rise to opioids' addictive effects. Vertex's drug works differently, blocking proteins that trigger pain signals that are later sent to the brain. "In trying to develop medicines that don't have the addictive risks of opioid medicines, a key factor is working to block pain signaling before it gets to the brain," Vertex's Dr. David Altshuler, told The Associated Press last year. Commonly reported side effects with the drug were nausea, constipation, itching, rash and headache.

An anonymous reader shares a report: At first blush, stock trading this week is hardly a paragon of the market-efficiency theory, an oft-romanticized idea in Economics 101. After all, big equity gauges plunged on Monday, spurred by fears of an AI model released a week earlier, before swiftly rebounding. A fresh academic paper suggests the rise of passive investing may be fueling these kind of fragile market moves.

According to a study to be published in the prestigious American Economic Review, evidence is building that active managers are slow to scoop up stocks en masse when prices move away from their intrinsic worth. Thanks to this lethargic trading behavior and the relentless boom in benchmark-tracking index funds, the impact of each trade on prices gets amplified, explaining how sell orders, like on Monday perhaps, can induce broader equity gyrations. As a result, the financial landscape is proving less dynamic and more volatile in the era of Big Passive, according to authors at the UCLA Anderson School of Management, the Stockholm School of Economics and the University of Minnesota Carlson School of Management.

More than 8,000 of the world's most-cited scientists have at least one retraction, according to a database that links retractions to top-cited papers. From a report: An analysis of the database, published in PLOS Biology on 30 January, attempts to map the scale of retractions and understand how they manifest. "Not every retraction is a sign of misconduct," says John Ioannidis, an epidemiologist at Stanford University in California, who led the study. "But it is important to have a bird's eye view, across all scientific fields, [of] people who are most influential in science."

Retracted papers had a higher number of self-citations than did non-retracted papers. And papers with higher co-authorship numbers were more likely to be retracted than those with fewer co-authors. [...] In the study, the authors split the most-cited scientists into two groups. The first featured the 217,097 authors who were among the top 2% most-cited in their fields over their careers. The second group comprised the 223,152 scientists who made up the top 2% for citation impact in 2023, the most recent year for which there were data. The authors found that 8,747 (4%) of the most highly cited researchers in 2023 had at least one retraction during their career, as did 7,083 (3.3%) of the researchers who were most-cited over their careers.

A study has found microplastic and nanoplastic pollution to be significantly higher in placentas from premature births than in those from full-term births. From a report: The levels were much higher than previously detected in blood, suggesting the tiny plastic particles were accumulating in the placenta. But the higher average levels found in the shorter pregnancies were a "big surprise" for the researchers, as longer terms could be expected to lead to more accumulation.

Preterm birth is the leading cause of infant death worldwide, and the reasons for about two-thirds of all preterm births were unknown, said Dr Enrico Barrozo, of Baylor College of Medicine in Texas, US. The established link between air pollution and millions of premature births had spurred the research team to investigate plastic pollution.

The new study only demonstrates an association between microplastics and premature births. Further research is needed in cell cultures and animal models to determine if the link is causal. Microplastics are known to cause inflammation in human cells, and inflammation is one of the factors that prompts the start of labour.

Mr. Dollar Ton shares a report from the BBC: The chemical building blocks of life have been found, among many other complex chemical compounds, in the grainy dust of an asteroid called Bennu, an analysis reveals. Samples of the space rock, which were scooped up by a Nasa spacecraft and brought to Earth, contain a rich array of minerals and thousands of organic compounds. These include amino acids, which are the molecules that make up proteins, as well as nucleobases -- the fundamental components of DNA. The findings are published in two papers in the journal nature.

Astronomers have discovered a newly identified asteroid that has a 1-in-83 chance of striking Earth on December 22, 2032, though the most likely scenario is a close miss. Designated as 2024 YR4, the asteroid measures in at 196 feet wide and is currently 27 million miles away. Space.com reports: The near-Earth object (NEO) discovered in 2024, which is around half as wide as a football field is long, will make a very close approach to Earth on Dec. 22, 2032. It's estimated to come within around 66,000 miles (106,200 kilometers) of Earth on that day, according to NASA's Center of NEO Studies (CNEOS). However, when orbital uncertainties are considered, that close approach could turn out to be a direct hit on our planet.

Such an impact could cause an explosion in the atmosphere, called an "airburst," or could cause an impact crater when it slams into the ground. This is enough to see asteroid 2024 YR4 leap to the top of the European Space Agency's NEO impact Risk List and NASA's Sentry Risk Table. "People should absolutely not worry about this yet," said Catalina Sky Survey engineer and asteroid hunter David Rankin. "Impact probability is still very low, and the most likely outcome will be a close approaching rock that misses us."

As for where it could hit Earth, Rankin said that the "risk corridor" for impact runs from South America across the Atlantic to sub-Saharan Africa.

Chinese scientists have created mice with genetic material from two males that survived to adulthood, marking a potential breakthrough in reproductive biology, according to research published in Cell Stem Cell. Researchers at the Chinese Academy of Sciences used CRISPR gene editing to target 20 genes involved in embryonic development, producing seven live pups from 164 embryos. The surviving mice grew larger than normal, had enlarged organs, were infertile and had shorter lifespans.

Genetic diversity in animals and plants has declined globally over the past three decades, an analysis of more than 600 species has found. From a report: The research, published in the journal Nature, found declines in two-thirds of the populations studied, but noted that urgent conservation efforts could halt or even reverse genetic diversity losses. Dozens of scientists internationally reviewed 882 studies that measured genetic diversity changes between 1985 and 2019 in 628 species of animals, plants, fungi and chromists (a type of organism), forming what they have called "the most comprehensive investigation" of changes in genetic diversity within species to date.

The study's lead researcher, Assoc Prof Catherine Grueber of the University of Sydney, said within-species diversity -- referring to the variation between individuals of the same species -- enabled a population to better adapt to changes in its environment. "If a new disease comes through, or there's a heatwave, there may be some individuals in the population that have certain characteristics that enable them to tolerate those new conditions," she said. "Those characteristics will get passed on to the next generation, and the population will persist instead of going extinct."