Early Arrival of Humans in China Surprises Researchers by Thousands of Years

The first members of our species to reach China may have entered this region from the north

Esteban de Armas / Alamy

Modern humans lived in what is now China by 45,000 years ago. This discovery means our species arrived in this region thousands of years earlier than commonly thought, probably via a northern route through present-day Siberia and Mongolia.

A team co-led by Francesco d'Errico Researchers from the University of Bordeaux in France reexamined an archaeological site in northern China called Shiyu. Originally, he was excavated in 1963 during the turbulent period of China's Cultural Revolution. “It couldn't have been a better time to find such an important site,” D'Errico says.

Shiyu is an outdoor site located in a river gorge. There, 30 meters deep, sand and other sediments were deposited, which the first excavators divided into four horizontal layers, from the bottom of which the second layer contained human It was found that there was evidence of residence in

Excavators discovered more than 15,000 stone artifacts and thousands of animal bones. There was also part of a hominin skull, which anthropologist Wu Lukang identified as a modern human.homo sapiens).

Some of the artifacts were later transferred to the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. However, those left behind at the local facility were lost, including the hominin bones. “We own maybe 10 percent of the stone tools,” D'Errico says.

D'Errico and his colleagues re-excavated Shiyu to determine its age. They dated 15 sediment samples using a technique called photostimulated luminescence and carbon-dated 10 animal bones and teeth. The hominid layer is approximately 44,600 years old.

D'Errico believes the excavator was “knowledgeable” and correctly identified the skull.

The Shuyu tribe is probably homo sapienssay Alina Katzenovic from the Institute of Archeology and Ethnology in Novosibirsk, Russia, was not involved in the study.

The new study therefore suggests that modern humans arrived in northern China about 45,000 years ago. This would postpone the arrival of our species to China by about 5,000 years.Derico claims to be the next oldest homo sapiens China's site Tengen Cave 40,000 years ago.

Some researchers argue that our species may have arrived earlier than that, up to 260,000 years ago. However, D'Errico points out that researchers: criticized much of the evidence As for the presence of such early humans in this region.

Humans probably entered Asia from Africa and spread through multiple routes, Katzenovich said. They not only explored the tropical southern regions of Asia, but also headed further north. Katzenovich says there are signs of modern human presence in the area. Obi Rakhmat Cave Uzbekistan 48,800 years ago. Perhaps our species reached Shiyu and then China via this route. north route.

When modern humans reached new areas, they encountered hominids that were already living there, such as Neanderthals and Denisovans further east. Genetic evidence shows that we interbred with them. There may also have been cultural exchanges, and the Shiyu artifacts also include what appear to be more ancient human tools.

There is also evidence of long-distance contact. The Shiyu team identified four fragments of obsidian, a volcanic glass. They were able to track them as far as 800 and 1000 kilometers northeast of Shiyu. D'Errico said it was unlikely that the residents traveled this distance themselves, so they were probably part of the group's network. In line with this, Kazenovich said some of Shiyu's artifacts resemble items found as far east as Korea.

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Source: www.newscientist.com

Discovery of new Tyrannosaurus species through early fossil findings

Artist's impression of Tyrannosaurus macraensis, a relative of Tyrannosaurus rex

sergei krasinski

A portion of a dinosaur skull discovered 40 years ago has been identified as a new species of dinosaur. tyrannosaurusand is probably the closest relative tyrannosaurus rex. The study adds a new twist to the long-standing debate about how many different tyrannosaurus species there were, and could help shed light on how the iconic predator evolved.

tyrannosaurus They first appeared in North America about 68 million years ago, 2 million years before the mass extinction event that wiped out most dinosaurs. Paleontologists are puzzled about the origins of this carnivore. Some suggest that it is an ancestor of tyrannosaurus Some people walked across land bridges from prehistoric Asia, while others traced their origins to southern North America.

Anthony Fiorillo Researchers from the New Mexico Museum of Natural History and Science reviewed fossils in the museum's collection that were discovered in a rock formation known as the McRae Formation in western New Mexico.

Skulls were originally classified as: tyrannosaurus, Fiorillo and his colleagues noticed differences in the bones.They proposed that this specimen represented an older species, which they named Tyrannosaurus macraiensis in reference to the rock in which it was found.

They estimated that the dinosaur was about 12 meters long, comparable in size to an aosaurus. Tyrannosaurus, However, it lived about 4 million years ago.

difference between tyrannosaurus and T. macraensis It would have been relatively subtle.on the other hand tyrannosaurus He had a prominent ridge on his eyebrow, and a bone-crushingly wide jaw with the same ridge. T. macraensis The body is less developed and the skull is thinner, Fiorillo said.

Jawbone identified as new species of Tyrannosaurus

nick longrich

Other recent studies have proposed that several species exist. tyrannosaurus And the so-called tyrannosaurus Fossils need to be reallocated. However, such proposals are controversial and are mostly rejected by dinosaur paleontologists. The new study is likely to spark further debate about that number. tyrannosaurus The species was found in North America.

“I hesitate to consider Tyrannosaurus macraiensis as different from tyrannosaurus rexJared Voris at the University of Calgary, Canada. He points out that many of the anatomical features that make the new species unique are also present in the specimen. tyrannosaurus.

Regardless of species assignment, the existence of such large tyrannosaurs millions of years ago is tyrannosaurus This suggests that southwestern North America was an important center of dinosaur evolution. “The age range of the proposed specimen is unique and requires further study,” Voris said. That's because it could outline a clearer picture of dinosaur evolution during the last few million years of the Cretaceous.

The New Mexico tyrannosaurus was discovered in the same rock as a giant horned dinosaur, an anthropomorphic duck-billed dinosaur, and a long-necked herbivore up to 30 meters long. Fiorillo and his colleagues tyrannosaurus It may have evolved to its gigantic size to prey on these large herbivores, and later spread north as the last “tyrant lizard” to stalk the planet.

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Source: www.newscientist.com

First American lunar lander in over five decades blasts off towards the moon, but faces early technical issues


Astrobotic said the cause of the failure was likely a propulsion failure, adding that a further update would be issued once more data is acquired and analyzed.

Peregrine’s mission represents a new chapter in the commercial space industry, launching private companies into the space race and delivering to NASA and other customers.

The Pittsburgh-based company First private company to succeed in landing This is something only four countries have achieved on the moon. A Houston-based company also has a lander ready to fly and is expected to take a more direct route to the moon.

NASA provided both companies with significant funding to build and fly their own lunar landers. The space agency hopes the privately owned lander will scout the site before astronauts arrive, while also providing technical and scientific experiments for NASA and benefiting other customers. Astrobotic’s Peregrine lander contract: $108 million.

During its first flight, the Peregrine lander carried five NASA instruments. Following the technical anomaly, NASA said it would learn from the situation.

“Each success and setback is an opportunity for us to learn and grow,” Joel Kearns, deputy assistant administrator for exploration at NASA’s Science Mission Directorate, said in a statement Monday. “We will use these lessons to advance our efforts to advance science, exploration, and commercial development of the Moon.”

The last time the United States launched a moon landing mission was in December 1972. Apollo 17’s Gene Cernan was the last human to set foot on the moon as mission commander, and Harrison Schmidt was the 12th astronaut to walk on the moon. , concluded an era that continued to be the pinnacle of NASA.

The space agency’s new Artemis mission, named after Apollo’s twin sister in Greek mythology, aims to return astronauts to the moon’s surface within the next few years. first, Flight around the moon by four astronautsProbably by the end of the year.

Highlighting Monday’s moonshot was the long-delayed initial test flight of the Vulcan rocket from Cape Canaveral Space Force Station. The 202-foot (61-meter) rocket is essentially an upgraded version of ULA’s highly successful flagship Atlas V, which will be phased out along with the company’s Delta IV. Jeff Bezos’ rocket company Blue Origin provided his two main engines for the Vulcan.

The then-Soviet Union and the United States suspended touchdowns after a string of successful moon landings in the 1960s and 1970s. China joined the elite club in 2013, India in 2023.But I also saw it last year Landing craft from Russia and Japanese private companies crash into the moon. In 2019, an Israeli nonprofit organization's lander crashed.

Next month, SpaceX will provide lifts for the lander from Intuitive Machines.

In addition to flight experiments for NASA, Astrobotic has launched its own cargo transportation business, shipping its 6-foot-tall (1.9-meter-tall) Hayabusa lander with rock chips from Everest and toy-sized objects it catapults from Mexico. I packed everything up to my car. It will reach and cruise the moon’s surface, collecting the ashes and DNA of deceased space enthusiasts, including “Star Trek” creator Gene Roddenberry and science fiction writer Arthur C. Clarke.

The Navajo Nation recently asked for the launch to be postponed because of the human remains. He said it would be a “grave desecration” of the celestial bodies worshiped by Native Americans. Thornton said the December challenge was too late, but promised to work to find a “good path forward” with the Navajo Nation for future missions.

Celestis, one of the spaceflight memorial companies that purchased space for the lander, said in a statement that no single culture or religion owns the moon and should not be able to veto the mission. There will be more debris in the rocket’s upper stage, and once released from the lander, it will orbit the sun indefinitely all the way to Mars.

Freight rates for Hayabusa range from a few hundred dollars to $1.2 million per kilogram (2.2 pounds), not enough for Astrobotic to break even. But Astrobotic CEO John Thornton says that’s not the point for this first flight.

“A lot of people’s dreams and hopes rest on this,” he said.

Source: www.nbcnews.com

Apple Vision Pro Expected to Launch between Late January and Early February

We’ve known about the Vision Pro for more than six months now (not to mention it’s been rumored for years), but Apple’s first “spatial computing” device is expected to arrive in consumer electronics heading into the new year. One of the biggest question marks. The $3,499 headset was given an “early 2024” release date when it was announced at WWDC in June, but the company hasn’t provided further specifics since then.

Apple oracle Ming-Chi Kuo Provided an early holiday gift He narrowed down the system’s release date to “late January to early February.” According to the analyst, the first Vision Pro will be shipped to Apple within about a month, bringing the total number of units shipped this year to about 500,000 units.

Company’s accurate target There are still open-ended questions remaining for this year. About a month after the device was announced, it was reported that Apple had reduced its forecast from around 1 million units to “less than 400,000 units.”

Even the latest figure of 500,000 is small for a company of Apple’s enormous size and influence. Keep in mind that the company should ship more than 200 million iPhones this calendar year.

But Vision Pro is widely considered to be Tim Cook’s biggest challenge in his 12 years as CEO. Not only is this an entirely new category and form factor for the company, but it’s also an exorbitant price point, even for customers accustomed to paying extra for Apple products. Add to that the fact that VR has not lived up to expectations for decades, and we have a big uphill battle ahead.

Kuo calls Vision Pro “Apple’s most important product in 2024.” That’s a tough statement to argue with, given years of speculation and all the time and money the company has undoubtedly poured into the headset.

Source: techcrunch.com

Utilizing New Technology to Detect Cancer Early: The Impact on Calderdale and Huddersfield NHS Foundation Trust in West Yorkshire

A West Yorkshire NHS Trust is utilizing advancements in technology, such as artificial intelligence and surgical robots, to achieve crucial cancer targets and alleviate widespread pressure on hospitals.

Calderdale and Huddersfield NHS The Foundation Trust is meeting three important cancer targets established by the government.

These targets include a waiting time of 28 days for patients who receive an emergency referral and are diagnosed with an infection or cancer, a 31-day wait from the patient’s treatment decision to the first treatment, and a 62-day wait from the emergency GP referral to the first treatment.

Sky News was given a tour of the innovations behind the hospital’s results, starting with a diagnostic test called Cytosponge. The Cytosponge is a small capsule with a string attached that is swallowed by the patient. When dissolved in the stomach, a brush collects cells from the esophageal lining, which are then analyzed for abnormalities.

image:
New diagnostic test site sponge could help doctors find cases of esophageal cancer faster

Cytosponges are used as an alternative to longer and more invasive endoscopies. Patients find the cytosponge less invasive and report a quicker procedure time.

Source: news.sky.com

Save 20% on a TechCrunch Early Stage 2024 pass when you buy by January 2nd

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For those not familiar with TC Early Stage, it is an important destination for ambitious startups and newly established startup founders. Here you can find leading founders, investors, entrepreneurs, and startup experts from across the technology ecosystem.

Learn from them in small group presentations and roundtables that focus on the core topics every founder needs to master.

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Don’t miss this sneak peek of the agenda featuring Engine Accelerator President Emily Knight. Tom Bromfield, Group Partner at Y Combinator. Rudina Seseri, co-founder and managing partner of Glasswing Ventures. more. We plan to add more sessions and speakers in the coming weeks.

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20% off passes To TechCrunch Early Stage 2024. buy a pass January 1st 11:59pm PT And we are determined to make 2024 the best year for startups ever.

Is your company interested in sponsoring or exhibiting at TC Early Stage 2024? Please contact our sponsorship sales team. Please fill out this form.

Source: techcrunch.com

Early Detection of Parkinson’s Disease Possible 30 Years Before Onset of Symptoms, Scientists Find

Researchers have discovered a way to detect Parkinson’s disease up to 30 years before symptoms appear using biomarkers and PET scans. This breakthrough includes tracking neurodegeneration more sensitively than current methods and shows that rapid eye movement sleep behavior disorder (RBD) is an important early indicator of Parkinson’s disease. is identified. This discovery could lead to earlier diagnosis and treatment, potentially up to 10 years earlier than currently.

Researchers at The Florey and Austin Health in Melbourne, Australia, have demonstrated the potential to identify early indicators of Parkinson’s disease 20 to 30 years before the onset of symptoms. This breakthrough paves the way for early screening programs and intervention, potentially allowing treatment before significant damage occurs.

Researchers at the Florey Institute and Austin Health have demonstrated the possibility of identifying early indicators of Parkinson’s disease 20 to 30 years before the onset of symptoms. This breakthrough paves the way for early screening efforts and preventive treatment, long before permanent damage occurs.

Florey Professor Kevin Burnham said that although Parkinson’s disease, a debilitating neurodegenerative disease, is often thought of as a disease of the elderly, it actually begins in midlife and can last for decades. He said it may not be detected.

“Parkinson’s disease is very difficult to diagnose until symptoms become apparent, by which time up to 85 percent of the neurons in the brain that control motor coordination have been destroyed. At that point, many treatments are likely to be ineffective,” Professor Burnham said. “Our long-term goal is to find ways to detect diseases earlier and treat people before they cause harm.”

Advanced diagnostic technology

In a recently published study, neurologylead researcher Professor Burnham and colleagues explore how a known biomarker called F-AV-133 can be used in positron emission tomography (PET) scans to diagnose Parkinson’s disease and accurately track neurodegeneration. I’m explaining how it can be done.

In the Melbourne study, Austin Health’s Frawley Professor Chris Rowe and his team studied 26 patients with Parkinson’s disease, 12 controls, and 11 patients with rapid eye movement sleep behavior disorder (RBD), a strong indicator of Parkinson’s disease. I checked the name. .

Each person underwent two PET scans two years apart. Key findings include:

  • Currently available assessments of Parkinson’s disease showed no significant changes in clinical symptoms in any of the participants.
  • In contrast, PET scans showed “significant neuronal loss” in three key areas of the brains of people with the disease, making F-AV-133 more effective than what is currently available. also suggests that it is a sensitive means of monitoring neurodegeneration.

Further mathematical modeling yields the following calculation:

  • Slow nerve cell loss over a total of approximately 33 years in Parkinson’s disease
  • This loss takes about 10.5 years before the disease is detected on a PET scan.
  • Even if a PET scan detects the disease, it will take another six and a half years for motor symptoms to appear.
  • It takes about 3 years after physical symptoms appear until a clinical diagnosis is confirmed.
  • This corresponds to approximately 22.5 years of neuronal loss before clinical symptoms are sufficient for diagnosis.

Professor Burnham said the findings pave the way for the development of screening protocols to diagnose and treat Parkinson’s disease up to 10 years earlier than is currently possible. It may also help identify patients for clinical trials.

What is RBD?

  • RBD stands for Rapid Eye Movement Behavior Disorder.
  • Patients with RBD scream, thrash, and sometimes move violently during sleep, enacting vivid and disturbing dreams.
  • RBD is caused by a lack of muscle relaxation (sleep paralysis).
  • 90% of RBD patients develop Parkinson’s disease.
  • Half of all Parkinson’s patients have RBD.
  • RBD is an important warning sign for early Parkinson’s disease.
  • If you have RBD, see a sleep specialist or neurologist.

Reference: “Use of 18F-AV-133 VMAT2 PET Imaging to Monitor Progressive Nigrostriatal Degeneration in Parkinson’s Disease”, Leah C. Beauchamp, Vincent Dore, Victor L. Villemagne, SanSan Xu, David Finkelstein, Kevin J. Barnham, Christopher Rowe, 28 November 2023 neurology.
DOI: 10.1212/WNL.0000000000207748

Source: scitechdaily.com

Astrobotic readies for early January launch of Peregrine lunar module

astrobotic‘s first lunar module is ready for launch.

The company announced Tuesday that the lander, called Peregrine, has completed final inspection and refueling after mating with United Launch Alliance’s Vulcan Centaur rocket last month. All that remains is the January 8th launch — and then, of course, the historic moon landing.

“If you’ve followed the lunar industry, you know that landing on the moon is incredibly difficult,” Astrobotic CEO John Thornton said in a statement. . “That being said, our team has continually exceeded expectations and demonstrated incredible ingenuity during flight reviews, spacecraft testing, and major hardware integration.”

“We are ready for launch and landing.”

The Peregrine lander, which is approximately 2 meters tall, will carry 20 payloads for government and commercial customers. The lander has a payload of 90 kg and will operate for approximately 192 hours after landing on the moon. During that time, it provides power and communications to the payload. According to Astrobotic’s payload user guide on his website, the company charges about $1.2 million per kilogram of mass delivered to the lunar surface.

Astrobotic is performing this mission as part of a $79.5 million contract from NASA under NASA’s Commercial Lunar Payload Services (CLPS) program. The company also won her second CLPS contract for the larger Griffin lander. The mission is scheduled to launch at the end of 2024.

Pittsburgh-based Astrobotic is one of the few commercial companies betting on the growing market for lunar payload delivery services. Other companies include Intuitive Machines, which aims to launch its first lander on January 12, days after Peregrine, Firefly Aerospace, and the Japanese company whose moon launch attempt failed earlier this year. Includes ispace etc.

After Peregrine lifts off from Cape Canaveral, Florida, the spacecraft will perform a series of burns to position it for landing on the moon’s surface on February 23.

Astrobotic isn’t the only company with a lot at stake in the January 8 launch. This mission also marks the first flight of United Launch Alliance’s Vulcan Centaur rocket. The rocket was hit by delays that postponed its debut for years. . ULA aims to launch several Vulcan flights next year and will ultimately need to sign a multibillion-dollar 38-vehicle launch deal with Amazon for its Project Kuiper satellite broadband constellation.

Astrobotic and ULA originally targeted a Dec. 24 launch date, but it was later postponed to give ULA time to complete a wet dress rehearsal. According to ULA, the wet dress was finally completed on December 14th.

Source: techcrunch.com

AI trained on extensive life stories has the ability to forecast the likelihood of early mortality

Data covering Denmark’s entire population was used to train an AI that predicts people’s life outcomes

Francis Joseph Dean/Dean Photography/Alamy Stock Photo

Artificial intelligence trained on personal data covering Denmark’s entire population can predict people’s likelihood of dying more accurately than existing models used in the insurance industry. Researchers behind the technology say it has the potential to have a positive impact on early prediction of social and health problems, but must be kept out of the hands of large corporations. There is.

Sune Lehmann Jorgensen The researchers used a rich Danish dataset covering the education, doctor and hospital visits, resulting diagnoses, income, and occupation of 6 million people from 2008 to 2020.

They converted this dataset into words that can be used to train large-scale language models, the same technology that powers AI apps like ChatGPT. These models work by looking at a set of words and statistically determining which word is most likely to come next based on a large number of examples. In a similar way, the researcher’s Life2vec model can look at the sequence of life events that form an individual’s history and determine what is most likely to happen next.

In the experiment, Life2vec was trained on all data except for the last four years of data, which was kept for testing. Researchers took data on a group of people aged 35 to 65, half of whom died between 2016 and 2020, and asked Life2vec to predict who lived and who died. This was 11% more accurate than existing AI models and life actuarial tables used in the financial industry to price life insurance policies.

The model was also able to predict personality test results for a portion of the population more accurately than AI models trained specifically to do the job.

Jorgensen believes the model has consumed enough data that it has a good chance of shedding light on a wide range of topics in health and society. This means it can be used to predict and detect health problems early, or by governments to reduce inequalities. But he stresses that it can also be used by companies in harmful ways.

“Obviously, our model should not be used by insurance companies, because the whole idea of ​​insurance is that if some unlucky person suffers some kind of incident, dies, loses their backpack, etc. ‘Because we share the lack of knowledge about what to do, we can share this burden to some extent,’ says Jorgensen.

But such technology already exists, he says. “Big tech companies that have large amounts of data about us are likely already using this information against us, and they are using it to make predictions about us. It is.”

Matthew Edwards Researchers from UK professional institutes the Institute of Actuaries and the Faculty of Actuaries say that while insurers are certainly interested in new forecasting techniques, the bulk of decision-making is based on a type of model called a generalized linear model. The research is done using AI, which he says is rudimentary compared to this research. .

“If you look at what insurance companies have been doing for years, decades, centuries, they’ve taken the data they have and tried to predict life expectancy from that,” Edwards said. “But we are deliberately conservative in adopting new methodologies, because when we are creating policies that are likely to be in place for the next 20 or 30 years, the last thing we want is to make any significant mistakes. . Everything can change, but slowly because no one wants to make mistakes.”

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Source: www.newscientist.com

Neanderthals May Have Been Early Risers, New Study Finds

When the ancestors of modern Eurasians migrated from Africa and interbred with the archaic humans of Eurasia, namely Neanderthals and Denisovans, the DNA of the archaic ancestors became anatomically integrated into the genomes of modern humans. homo sapiens. This process could accelerate adaptation to Eurasian environmental factors, such as reduced UV radiation and increased seasonal variation. In a new study, scientists from Vanderbilt University, the University of Pennsylvania, and the University of California, San Francisco have discovered lineage-specific genetic differences in circadian genes and their regulatory elements between humans and Neanderthals. They found that the introgressed genetic variants were enriched with effects on circadian regulation and consistently increased morningness tendencies in Europeans. The results expand our understanding of how the genomes of humans and our closest relatives responded to environments with different light-dark cycles.

Velasquez Alsuley other. They found that genetic material from Neanderthal ancestors may contribute to the tendency of some people today to be early risers, the type of people who wake up early and go to bed more easily. Image credit: Holger Neumann / Neanderthal Museum.

All anatomically modern humans trace their origins to the African continent about 300,000 years ago, where environmental factors shaped many of their biological characteristics.

They arrived in Eurasia 70,000 years ago, but other humans, Neanderthals and Denisovans, lived there for more than 400,000 years.

These archaic humans diverged from anatomically modern humans about 700,000 years ago, and as a result, humans and archaic hominid ancestors evolved under different environmental conditions.

“Although there was considerable variation in the latitudinal range of each group, Eurasian hominids primarily lived at consistently high latitudes and were therefore exposed to larger amplitude seasonal fluctuations in photoperiod,” said the University of California. said the San Francisco school. Dr. John Capra and his colleagues.

“Given the influence of environmental cues on circadian biology, we hypothesized that these separate evolutionary histories produced differences in circadian traits adapted to different environments.”

Although previous studies have shown that many of the archaic ancestors of modern humans are not beneficial and have been removed by natural selection, some archaic hominin variants that remain in human populations has shown evidence of adaptation.

For example, archaic genetic variation is thought to be associated with differences in hemoglobin levels, immune resistance to new pathogens, levels of skin pigmentation, and fat composition among Tibetans at high altitudes.

Changes in patterns and levels of light exposure have biological and behavioral effects that lead to evolutionary adaptations.

Scientists have extensively studied the evolution of circadian adaptations in insects, plants, and fish, but humans have been less well studied.

The Eurasian environment where Neanderthals and Denisovans lived for hundreds of thousands of years is located at higher latitudes and has more variable daylight hours than where modern humans evolved before leaving Africa.

Dr. Capra and his co-authors therefore investigated whether there was genetic evidence for differences in circadian clocks between Neanderthals and modern humans.

Using a combination of literature searches and expert knowledge, they defined a set of 246 circadian genes.

They found hundreds of genetic variations unique to each strain that can affect genes involved in the circadian clock.

Using artificial intelligence techniques, they identified 28 circadian genes that contain mutations that could alter splicing in archaic humans and that may be differentially regulated between modern and archaic humans. identified 16 circadian genes.

This indicates that there may be functional differences between the circadian clocks of ancient and modern humans.

Eurasian modern humans and Neanderthal ancestors interbred, so some humans may have acquired circadian variation from Neanderthals.

To test this, researchers investigated whether introgressed genetic variants were associated with the body’s preferences for wakefulness and sleep in a large cohort of hundreds of thousands of people at UK Biobank. did.

They found a number of introgressed mutants that affected sleep preferences, and most surprisingly, they found that these mutants consistently increased morningness, or the tendency to rise early.

This suggests a directional influence on this trait and is consistent with adaptations to high latitudes observed in other animals.

Increased morning time in humans is associated with a shortened circadian clock period. This may be beneficial at high latitudes, as it has been shown that sleep and wakefulness can be coordinated more quickly with external timing cues.

Shortening of the circadian period is required to synchronize the long summer light period at high latitudes in Drosophila, and selection for a shorter circadian period results in a latitudinal shift with increasing latitude in natural Drosophila populations. There is a latitudinal gradient in which the period decreases.

Therefore, the bias toward morningness in introgressed mutants may indicate selection for shortened circadian periods in populations living at high latitudes.

The tendency to be a morning person may have been evolutionarily beneficial to our ancestors who lived in the high latitudes of Europe, and would have been a Neanderthal genetic trait worth preserving.

“By combining ancient DNA, extensive genetic studies in modern humans, and artificial intelligence, we discovered substantial genetic differences in the circadian systems of Neanderthals and modern humans,” Dr. Capra said. .

“And by analyzing fragments of Neanderthal DNA that remain in the genomes of modern humans, we discovered surprising trends, many of which influence the regulation of circadian genes in modern humans. These effects are primarily in the consistent direction of increasing Neanderthal tendencies.” Morning people. ”

“This change is consistent with the effects of living at high latitudes on animals’ circadian clocks, and changes in seasonal light patterns may allow them to adjust their circadian clocks more quickly. ”

“Our next steps include applying these analyzes to more diverse modern human populations and investigating the effects of the Neanderthal variants we identified on circadian clocks in model systems. and applying similar analyzes to other potentially adaptive traits.”

of the team paper It was published in the magazine Genome biology and evolution.

_____

Kayla Velasquez-Arsley other. 2023. Archaic genetic introgression shaped human circadian characteristics. Genome biology and evolution 15 (12): evad203; doi: 10.1093/gbe/evad203

Source: www.sci.news

How did Paranthropus, a peculiar, ape-like early hominin, manage to survive for so long?

P. Prairie/E. Daines/Science Photo Library

It’s not often that a respected professor embarks on an investigation into a scientific discovery by a 15-year-old, but in 1938 Robert Bloom made an exception. The British-born paleontologist was keenly aware that South Africa in the 1930s was gaining a reputation for extremely primitive-looking hominin fossils. So when he heard that elementary school student Gerd Terblanche had discovered a fragment of a human skull in a cave there, he immediately tracked him down. Bloom’s visit to the boy’s school was successful. The boy later recalled that he was walking around with children. “Probably the world’s four most precious teeth are in his pants pocket.”.

Within a few months, Bloom completed his analysis of the fossil. He determined that they were different from anything previously discovered; He gave ancient humans a new name. paranthropus.

However, although he was convinced that the remains were valuable, paranthropus He never became famous. Perhaps it was because it was a misfit. It resembled one of our small-brained ancestors, but existed on Earth long after other ape-like hominids were replaced by large-brained hominins. Even among paleoanthropologists, paranthropus They are depicted as a “forgotten” human race.

It probably won’t last very long. Spurred by the discovery of more fossils, researchers are finally starting to re-evaluate this addition to the evolutionary tree – and their research suggests it was one of the strangest. ing. paranthropus They may have been skilled tool makers, but they also may have grazed like cows and communicated with low calls like elephants. The question now is whether this research will bring us any closer to understanding how the last apemen survived in a world dominated by…

Source: www.newscientist.com

Bluesky, X’s competitor, reaches 2 million users; federation to launch in early next year

Bluesky is a company building a decentralized alternative to Twitter/X. announced It now has 2 million users, an increase of another 1 million since September, despite still being an invite-only app. It also revealed deadlines for other important goals, saying it plans to have a public web interface up and running by the end of this month and start federation by early next year.

The latter is one of the most important differentiators between Bluesky and X, as it allows Bluesky to function as a more open social network. This means it works more like Mastodon, where users can choose which servers to join and move their accounts around freely. This is what Bluesky today claims is “billionaire-proof” and criticizes Elon Musk’s ownership of Twitter, now known as X.

“Rather than being bound to the whims and black-box algorithms of private companies, you have the freedom to choose (and exit) at any time.” Explained in company blog post. “And wherever you go, your friends and relationships will be there too,” it states.

Similar to Mastodon, a decentralized service, federation allows anyone to run their own service and connect to other services running the same protocol. For Bluesky, this is done like this: AT protocol The company is also developing consumer services and mobile apps in parallel. But his other major decentralized social network, Mastodon, uses an established protocol, his ActivityPub, which has grown significantly in the months since Musk’s acquisition of Twitter. It is attracting attention.

Since then, other companies have adopted ActivityPub and Mastodon, including Mozilla, Flipboard, Medium, and Automattic (WordPress.com’s parent company). Unless Bluesky makes the AT protocol and ActivityPub interoperable in some way, there could be challenges regarding Bluesky’s ultimate reach. Bridging Maybe the two of you Technically It’s possible, but it’s more likely to be in the future, not in the near future.

Meanwhile, Bluesky is working to make its services more accessible, including launching a public web interface later this month. This will allow anyone to view his Bluesky posts, even if they don’t have an account. This could make the network more promising in terms of being a true competitor to X in breaking news and conversation, but it could expose Bluesky users’ posts to the outside world in ways they are not ready for. There is also. (This app currently does not have an option to set your profile to “private” like Twitter/X does. some users is not Happy about this. )

Despite its growth, Bluesky’s reluctance to drop its invite-only status and open its network to more users has allowed other competitors of X to gain a foothold. Last month, for example, Meta CEO Mark Zuckerberg announced that Instagram Threads, an alternative to X, had just under 100 million monthly active users. He believes he can reach 1 billion users in the next few years. Threads also plans to interoperate with ActivityPub in the future.

Bluesky’s announcement follows Threads’ rapid release of features to make the app more competitive with X, including a chronological feed, support for displaying likes, search, and (free) Includes an edit button, web version, voting, GIF support, and more. , topic tags, and soon a developer API. Mastodon also took advantage of the opportunity presented by the Twitter acquisition and launched an easier-to-use version of its service in September of this year. However, Mastodon currently has 1.6 million monthly active usersHowever, it is much smaller than a thread.

In addition to today’s news, Mr. Bluesky also provides mobile push notifications, shareable user lists, email verification, advanced feed and thread settings for sorting and filtering posts, a media tab in user profiles, and a user profile for your own users. We also mentioned other recently released features, such as a Likes tab for profiles. , the suggestions below, and various accessibility improvements.

Bluesky started life as a Twitter project under Jack Dorsey, but the company was spun off from Twitter. $13 million How to start research and development. Mr. Dorsey sits on its board of directors. This year, the company raised an $8 million seed round led by Neo to further its development and transformed from a public benefit LLC to a public benefit C Corp.

Source: techcrunch.com