Analysis of large amounts of dinosaur and bird fossils has suggested that the evolution of primitive birds was slow and the diversity of body shapes dropped, which is opposite to the common belief that quick and major changes occur when a new species is taking shape.
The discovery was made by Wang Min and Zhou Zhonghe from the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences. An article about the research has been published by Nature Ecology & Evolution, a sub-journal of Nature.
Vertebrate evolution from dinosaurs to birds was an epic moment in natural history and the process involved many changes in bones, muscle and skin, which are related to flying, according to a press release the institute sent to the Global Times on Monday.
One of the most notable changes was in body shape, represented by the length of the limb bones. Theropod dinosaurs, which are closer to birds in the evolutionary tree, have relatively long forelimbs. Therefore, a systematic quantitative analysis of the dynamic evolutionary trajectory of limb bones during the origin of birds is key to understanding the important transition from "dinosaurs running on land" to "dinosaurs (birds) flying in the blue sky."
Researchers established a model to analyze the limb bones of avialans (birds), non-avialan paravians (dinosaurs similar to but not the same as birds) and non-paravian theropods, finding that diversity of avialans was the lowest while for non-paravian theropods it was the highest. An estimate of limb bone evolution speed indicated the evolution "slowed down" among avialans, or primitive birds.
Analysis also found two other indexes, which represented the flying pattern and cursorial pattern, were also the lowest among birds, indicating a low evolution speed.
These findings go against the common sense that the diversity and evolution speed increase at an epic evolutionary juncture.
One hypothesis is that birds' forelimbs can only have limited changes within the aerodynamic frame, and many characteristics related to flying had already appeared among theropods.
China's Hong Kong Special Administrative Region (HKSAR) has newly launched the city's first and one of the world's largest satellite manufacturing facilities, known as AMC. The facility revealed to the Global Times in an exclusive interview that their first made-in-Hong Kong, high-quality satellite would hopefully be delivered by the beginning of 2024.
Referred also as the ASPACE Hong Kong Satellite Manufacturing Center under the HK Aerospace Technology Group, the AMC, was launched on July 25, marking an important milestone in the development of the city's aerospace technology industry.
AMC is located at the Tseung Kwan O Industrial Estate and covering a site area of 200,000 square feet (approximately 18,580 square meters,) or three and a half football fields, the center hosts 18 subsystems and over 200 sets of equipment, covering various comprehensive production line equipment including satellite overall structure, optical calibration, vibration, mechanical performance, electromagnetic compatibility, thermal control, and precision, etc. It can provide the most comprehensive system production support for satellites and various related aerospace products before they leave the factory, AMC said in responding to the Global Times' inquiries via email.
According to AMC, at the early stage following its launch, its main products include remote sensing satellite constellation (both optical and radar,) key payloads such as synthetic aperture radar (SAR) and optical cameras, etc., used to obtain more detailed and accurate Earth observation data.
AMC would also provide customized technologies, including developing customized products according to specific use requirements, such as carbon monitoring satellites, meteorological satellites, etc., for monitoring and forecasting in specific fields.
AMC will also work to manufacture communication satellite constellation to provide global communication services and meet the communication needs of governments and commercial companies, navigation enhancement satellites to provide more accurate and reliable navigation positioning services, meeting the navigation needs of transportation departments and individual users, and multi-functional integrated satellites that integrate communication, navigation, and remote sensing functions to provide various application services. The Hong Kong-based satellite manufacturing center said their main customers include government departments such as the China Meteorological Administration, environmental protection departments, transportation departments, commercial companies in the fields covering land asset management, carbon trading, ESG service products, research institutions including universities, key astronomical research laboratories, and remote sensing application laboratories, and individual users.
"The AMC satellites procurement and satellite applications require close cooperation with the mainland, especially in areas such as production line research and development, satellite product upgrades, satellite launch and orbit control, and supplier solutions," the group explained in the email it provided to the Global Times.
It is worth noting that China successfully launched the Golden Bauhinia-3, -4 and -6 satellites via the Long March-2D carrier rocket from Taiyuan Satellite Launch Center on January 15, 2023. Those satellites are developed by the HK Aerospace Technology Group.
The group has successfully launched 12 satellites for its Golden Bauhinia Constellation project so far and plans to manufacture and launch the remaining satellites under the Golden Bauhinia Constellation project during the period from the end of 2023 to 2026.
The constellation is an active-passive hybrid low-orbit high-frequency satellite constellation that combines optical remote sensing and synthetic aperture radar to form an all-weather and near-real-time dynamic monitoring system.
AMC highlighted that after the comprehensive deployment of our Golden Bauhinia satellite constellation, they will consider user groups in the Greater Bay Area as an early priority and provide long-term satellite data application services to support its smart city construction, environmental governance, climate monitoring, and other key areas.
Chinese space observers hailed on Monday that as the country's space strengths have advanced to the first-class tier worldwide, science and research institutions such as universities in the Hong Kong SAR could fully play their part by keeping up the country's momentum, fully displaying their basic research and innovation capabilities, especially in the aerospace domain.
It is important for Hong Kong to play its due part as the innovation center and forerunner in the Greater Bay Area, which is in line with the national positioning of the city, Song Zhongping, a Hong Kong-based space watcher and TV commentator, told the Global Times on Monday.
In return, Hong Kong could bridge and improve international cooperation in space with the China as the city does in other fields, he added.
Also, as an international hub, Hong Kong could launch their satellites not only from the Chinese mainland, but also from overseas. The robust aerospace development could bring forth new economic growth and inject impetus to the city, Song noted. The target market for ASPACE Hong Kong Satellite Manufacturing Center is expected to grow to $30 billion by 2027, according to the Hong Kong-based South China Morning Post.
Sun Dong, Secretary for Innovation, Technology and Industry of the HKSAR government, said that the centre will be the most advanced satellite manufacturing centre in Asia in the next three to five years.
In fact, both the HKSAR and China's Macao Special Administrative Region have become increasingly involved in the country's major space program.
According to the China Manned Space Agency (CMSA) on May 29, the selection of the fourth group of taikonauts, China's new generation of astronauts, is proceeding as planned and will be completed by the end of this year, and more than 100 candidates then entered the second round, including more than 10 from Hong Kong and Macao.
The selection process was launched in 2022 and will result in 12 to 14 reserve taikonauts being picked, each with different specialisms, such as spacecraft pilots, flight engineers and payload specialists, per the CMSA's previous comments.
South China’s Shenzhen vowed on Wednesday to intensify its crackdown on ill-intentioned speculation and smears against private businesses among its newly 20-point measures to boost the private economy, according to Shenzhen Fabu, the official WeChat account of the Shenzhen Government Information Office.
The move marks a prompt response from local authorities to implement the comprehensive guidelines recently issued by the central government to support the private sector.
According to the measures, Shenzhen will step up efforts to combat deliberate speculation, rumors, and defamation against private enterprises and entrepreneurs. The city will also crack down on "online blackmouths" in accordance with the law to create a favorable social atmosphere that respects and supports the growth of private entrepreneurs.
The city will also actively promote leading private enterprises in emerging fields such as new energy vehicles, artificial intelligence, and new energy storage. Moreover, it will foster national and provincial-level characteristic industrial clusters for small and medium-sized enterprises.
To strengthen financing support for private enterprises, Shenzhen will establish a 5 billion yuan ($685 million) fund to hedge risks in loans to small and micro enterprises and reduce the guarantee fee rate for financing these enterprises by government financing institutions to below 1 percent.
Efforts will also be made to support private companies in expanding the overseas market and participating in overseas projects brought by opportunities from the Belt and Road Initiatives and the Regional Comprehensive Economic Partnership.
Shenzhen is home to a long list of renowned private firms such as Huawei, Tencent, and BYD. Its private sector has been one of the most dynamic in major Chinese cities, playing an outsized role in the city’s economy, according to Shenzhen Daily.
By the end of 2022, there were 2.379 million private companies in Shenzhen, accounting for 97 percent of the city’s overall firms. The private economy comprised 55.9 percent of the city’s GDP, according to the report.
That’s the score after the first match between Lee Sedol, the world’s top Go player and AlphaGo, the computer program that recently defeated the European Go champion.
AlphaGo is the creation of Google DeepMind, an artificial intelligence company based in London. The company’s program is the first to give top human players a run for their money in Go, a complex Chinese strategy game that almost makes chess look like Candy Land.
AlphaGo and Sedol will play four more matches over the next week in Seoul, South Korea. The winner will receive a $1 million prize and, perhaps more importantly, secure a place in history as either the man who triumphed over the best Go-playing machine ever created — or the first machine to surpass humankind’s players.
A new refrigerator-sized factory can rapidly pump out a diverse assortment of drugs on demand.
Researchers designed the system to offer a speedy alternative to large-scale pharmaceutical production. Rejiggering chemical inputs and the device’s collection of tanks and tubes allowed the team to produce four different drugs: an anesthetic (lidocaine), an antihistamine (Benadryl), an anti-anxiety medication (Valium) and an antidepressant (Prozac). The self-contained system was equipped to mix, heat, pump and purify ingredients into hundreds to thousands of doses of pharmaceutical-grade compounds. Making each medication took the device between roughly 12 and 50 hours, the team reports in the April 1 Science. Attached computers allow one person to control and monitor the whole process.
For now, the device only makes liquid medications. But it may be a step toward overcoming limitations of cumbersome drug-making supply chains by developing automated tools that make medications on demand.
The Kepler space telescope, NASA’s premier planet hunter, is about to embark on a hunt for planets toward the center of the galaxy. But on April 7, just hours before its new mission was set to begin, the observatory gave astronomers a scare by temporarily hunkering down in an emergency state that prevented mission controllers from communicating with the spacecraft. As of April 11, though, Kepler was talking to Earth again, and engineers are getting the telescope prepped for its new quest.
“A cause has not been determined; that will take time,” says NASA spokesperson Michelle Johnson. “The priority is returning the spacecraft to science mode.” Kepler has previously had problems with its reaction wheels, which are necessary for keeping the spacecraft pointed in the right direction. After two of its wheels stopped working, the telescope took a break from planet hunting in 2013. Engineers at Ball Aerospace figured out how to get Kepler working again with the two remaining wheels by using pressure from sunlight to balance the telescope. While engineers don’t yet know why Kepler shut down this time, early reports indicate that the remaining reaction wheels are not to blame.
Once the spacecraft checks out, Kepler will kick off its latest effort, looking toward the galactic center for planets whose gravity distorts the light from far more distant stars. This technique, known as gravitational microlensing, has been used with ground-based telescopes to discover about 46 planets, some of them orphaned from their parent stars. But the method is a first for Kepler, which searches for dips in starlight caused by planets crossing in front of their suns.
This phase of Kepler’s mission will last until July 1. Even if it doesn’t turn up any new exoplanets, it’s guaranteed to see at least one world: To look at the center of the galaxy, Kepler has to point toward Earth. The telescope that has spent over half a decade searching for other worlds will snap a picture of our planet that will be released later this year.
SALT LAKE CITY — When black holes collide, astronomers expect to record a gravitational wave “chirp.” But rapidly spinning black holes, like the one featured in the 2014 film Interstellar, might prefer singing to chirping.
According to the calculations of Caltech physicist Kip Thorne, who served as scientific consultant for Interstellar, the movie’s black hole, known as Gargantua, must have had a mass 100 million times that of the sun and whirled about its own axis at breakneck speeds. These characteristics would explain the extreme time dilation on the world where the film’s intrepid planet hunters landed: In one hour there, seven elapsed on Earth, a phenomenon predicted by Einstein’s general theory of relativity. If a rapidly spinning black hole merges with a companion, it would produce a unique signal — one that gravitational wave detectors might be able to observe, physicist Niels Warburton of MIT reported April 18 at a meeting of the American Physical Society. “There is a completely different gravitational wave signature,” said Warburton, who coauthored a related paper posted online at arXiv.org on March 3.
The standard signal of merging black holes is a “chirp,” named for the increase in frequency and amplitude of the gravitational waves produced as the black holes spiral inward. When converted into sound waves, this pattern sounds like a bird’s chirp. Warburton and colleagues performed calculations to determine the gravitational wave signature from a merger with a black hole spinning at nearly full tilt. Instead of a chirp, they found the gravitational waves would instead maintain a constant pitch, but slowly fade away.
“It was certainly very unexpected to see something that didn’t chirp,” says physicist Jolyon Bloomfield of MIT, who was not involved with the research. “This is really quite interesting work. It shows that the chirp actually goes away — something else is happening here.”
If such black hole mergers occur in nature, next-generation gravitational wave observatories like the Evolved Laser Interferometer Space Antenna might provide proof of their existence. Plans call for eLISA to measure gravitational waves from space beginning in 2034. “These are definitely detectable with eLISA,” Warburton said.
The Advanced Laser Interferometer Gravitational-Wave Observatory, which made the first detection of gravitational waves in 2015 (SN: 3/5/16, p. 6), might be able to observe such mergers if the conditions were just right. Although LIGO can’t observe the mergers of black holes as massive as Gargantua, smaller spinning black holes would produce a similar effect. Finding black holes like Gargantua would have an impact beyond Hollywood. Spinning black holes are “really interesting from a fundamental physics point of view,” says Samuel Gralla of the University of Arizona in Tucson, a coauthor on the new paper.
Black holes can spin up faster and faster as they suck in matter, but scientists think there’s a limit to how fast they can go. At the center of a black hole is a singularity, or region of infinite density, which is hidden by an event horizon — the surface beyond which nothing can escape the black hole’s greedy pull. But if the black hole twirls too fast, the singularity becomes exposed. Such a “naked singularity,” as it is known, is thought to be impossible to reach, because the known laws of physics would break down.
According to the scientists’ calculations, black hole mergers sing when the larger black hole is rotating just below the limit, at 99.99 percent of its maximum speed. This makes singing black holes an enticing prospect for understanding physics at its extremes.
Over the years, readers have on occasion written to me to point out what they see as an increasing politicization of Science News. These are not accolades — more than one of those readers has contemplated ending their subscription. Some of those critics deny climate change, some oppose GMOs, others view any policy discussion in our coverage as worrisome. So, are we actually getting involved in politics? My short answer is no. But there are many areas in which science has important things to say to citizens and policy makers. And reporting on the body of evidence that relates to societal issues falls fully within our mission, even for scientific questions with political ramifications. It’s well worth the ink to inform people about pressing problems or provide factual information in what have become hotly contested and polarizing debates. Science can help establish what’s known, what’s not known and how scientists might find answers. That’s what Science News reports on, with the aim of giving readers not a political argument but a clear idea of where the evidence currently stands and what questions remain. Facts based on sound science can perhaps even provide a common ground for people of differing opinions to speak to each other rationally.
In the case of what researchers can say with respect to the efficacy of gun laws, it turns out that there are more questions than answers. The numbers on U.S. gun violence are clear: In 2013, the United States had many more gun-related deaths than other nations with similar standards of living. But as Meghan Rosen investigated the state of the knowledge, it became evident that now, in the United States, it’s hard to even do the science. Researchers told her that they just don’t have the data needed to answer questions about the impacts of different gun control laws.
“I thought the evidence behind well-known gun control policies would be more clear-cut,” Rosen says. But studies of background checks, waiting periods and a 1994 assault weapons ban don’t necessarily show a corresponding reduction in gun violence. Maybe such laws don’t do what lawmakers intended, but there are also confounding factors that may dilute any conclusions, Rosen reports. The 1994 ban on assault weapons, for example, stopped only sales of new weapons and didn’t apply to those already in circulation. Most disturbing to Rosen was the blocking of scientific research by Congress, which has maneuvered to stop the Centers for Disease Control and Prevention and the National Institutes of Health from doing or funding work that might advocate or promote gun control laws. That has effectively reduced research into the best ways to prevent gun violence.
The science that has been done on whether U.S. gun control laws reduce gun violence has been mixed. There aren’t a lot of straightforward answers to guide policy. But in this case, science has not had a fair chance to build the foundation for an evidence-based conversation. Without facts, it really is all political. Our aim is to find and report on those facts (or the lack of them), so that they can become part of the conversation.
A gut microbe collected from chinchilla droppings might be the first complex life form to lack even a shred of a supposedly universal organelle.
Monocercomonoides, a one-celled gut microbe collected from a pet chinchilla in Prague decades ago, apparently has no mitochondria, the organelles known as the cell’s power plants. Cataloging DNA in the microbe turns up none of the known genes for mitochondrial proteins. But stealing genetic material from bacteria — which survive without mitochondria — allowed the microbe to do without them, too, researchers report May 12 in Current Biology. Mitochondria are tiny capsules that speckle the insides of all complex cells from pond scum to people, or so textbooks have said for decades. Some complex (or eukaryotic) cells look as if they have no mitochondria; so far, though, further searches have eventually detected mitochondrial remnants.
But Monocercomonoides appears to have completely done away with mitochondria and the genes to make them, says study coauthor Anna Karnkowska, an evolutionary biologist now at the University of British Columbia in Vancouver.
This discovery marks “the most extreme mitochondrial reduction observed,” says Vladimír Hampl of Charles University in Prague, also a coauthor of the study.
The new work also supports the idea that there really is no single core function that defines mitochondria. Although commonly described as cell powerhouses, mitochondria don’t have much to do with supplying energy for cells that live in low-oxygen or no-oxygen environments, Karnkowska says. For these anaerobic cells, mitochondria can serve as more of a building studio. One supposedly essential mitochondrial function, scientists have proposed, is assembling clusters of iron and sulfur that activate a class of widely useful cell compounds.
Bacteria and other simple (prokaryotic) cells have their own assembly systems, and they don’t need to wall off the construction of iron-sulfur clusters. The newly studied Monocercomonoides carry the genes for an assembly system that looks as if it was taken from bacteria, the researchers conclude. Researchers discovered the lack of mitochondrial genes and the bacterial substitute while working out the DNA components that encode instructions for all the proteins in the whole organism. There were notably no signs of chaperone proteins for conveying other proteins through membranes, something mitochondria do. Nor did other signature mitochondrial proteins show up.
“Pretty amazing story,” says Roland Lill of Philipps University of Marburg in Germany, who studies the way cells use iron. The new paper doesn’t change the basic idea that complex cells need very special conditions, usually created only inside mitochondria, to build their iron-sulfur clusters. “But the beauty of biology,” he says, “is that there are always amazing exceptions to basic biological rules.”
Laser blasts might help scientists tweak Earth’s thermostat by shattering the ice crystals found in cirrus clouds.
Zapping tiny ice particles in the lab forms new, smaller bits of ice, researchers report May 20 in Science Advances. Since clouds with more numerous, smaller ice particles reflect more light, the technique could combat global warming by causing the clouds to reflect more sunlight back into space, the scientists say.
Scientists from the University of Geneva and from Karlsruhe Institute of Technology in Germany injected water drops into a chilled chamber that mimics the frigid conditions high in the atmosphere, where wispy cirrus clouds live. The water froze into spherical ice particles, which the scientists walloped with short, intense bursts of laser light. When the laser hits an ice particle, ultrahot plasma forms at its center, producing a shock wave that breaks the particle apart and vaporizes much of the ice. The excess water vapor left in the aftermath then condenses and freezes into new, smaller ice particles. Applying this technique to clouds is “a long, long, long way in the future,” says physicist Mary Matthews of the University of Geneva, a coauthor of the study. Current laser technology is not up to the task of cloud zapping — yet. “What we are hoping for is that the advances in laser technology, which are moving faster and faster all the time, will enable high-powered, mobile lasers,” Matthews says.
But tinkering with cirrus clouds could backfire if scientists aren’t careful, says atmospheric scientist Trude Storelvmo of Yale University. The clouds also trap heat, through the greenhouse effect, so breaking up their ice particles could actually warm the Earth. The method“could potentially work, but only if you target certain types of cirrus clouds,” she says, such as those that are very thick.
There could also be warming if fossil fuels are burned to power the laser, says David Mitchell of the Desert Research Institute in Reno, Nev. “I think it’s really interesting research, but I’m just not seeing how it’s going to make the world a cooler place.”
