While OpenAI has been continuously iterating and gaining widespread attention in the past few months, Google finally dropped a bombshell by unveiling its long-awaited multimodal model, Gemini, which Google itself touted as "the most capable model" they've ever built.
Chinese analysts say it can help Google catch up with OpenAI in the generative AI race, which also teaches a lesson to Chinese AI developers that latecomers can narrow the gap through non-stop effort.
Considered as the biggest competitor to ChatGPT in the market, Gemini encompasses three AI models - Gemini Nano, Gemini Pro and Gemini Ultra - each serving different purposes.
Gemini Ultra's performance exceeds current state-of-the-art results on 30 of the 32 widely-used academic benchmarks in large language model (LLM) research and development, ranging from natural image, audio and video comprehension to mathematical reasoning, Demis Hassabis, the co-founder and CEO of DeepMind, wrote in a Google blog on Wednesday.
Once released, worldwide news media splashed the story all over. Some Chinese media wrote the headline that "AI industry ushers in further catalysis with Gemini release." Zhong Junhao, secretary-general of the Shanghai Artificial Intelligence Industry Association, told Chinese media that Gemini will deal "a disruptive blow to OpenAI" as Google has created a mature AI development ecology, citing its vast range of deployment in hardware devices, search engines and chips as well as the new-generation large model.
According to Hassabis, Gemini better understands nuanced information and can answer questions relating to complicated topics, like explaining reasoning in complex subjects including math and physics. It is also capable of understanding, explaining and generating high-quality code in the world's most popular programming languages, like Python and Java.
Gemini Nano is a lightweight version designed for offline use on Android devices. On the other hand, Gemini Pro is a more powerful model that will be utilized in various Google AI services and now Bard makes use of Gemini Pro. Gemini Ultra is scheduled for release next year.
Starting from December 13, developers and enterprise customers can access Gemini Pro through Google Generative AI Studio or Vertex AI in Google Cloud. Although currently available only in English, Google plans to expand Gemini to support other languages in the near future. Ultimately, Google aims to integrate Gemini into its search engine, ad products, Chrome browser and more on a global scale, media reports said.
Google is still trying to catch up in the field of LLMs. OpenAI has a significant advantage in this AI race due to its large user base, and user feedback will only accelerate its development, Xiao Yanghua, a computer science professor at Fudan University, told the Global Times.
The launch of Gemini is a crucial step for Google to catch up for sure, as it is advanced enough to achieve the level of GPT-4. However, surpassing OpenAI's GPT family may prove challenging. Xiao mentioned that the industry needs to wait and see as GPT-5 is officially on the OpenAI roadmap.
According to the comparison results released in Google's Wednesday blog, with OpenAI's current strongest LLM, GPT-4, the results indicate that Gemini Ultra outperforms GPT-4 in areas such as reasoning, mathematics and coding, with the exception of text processing, where GPT-4 scored 86.4 percent compared to Gemini Ultra's 90 percent in MMLU (massive multitask language understanding).
The claimed improvements over GPT-4 are in their own chosen tasks and most of the improvements are only different by a few percentage points, while in audio processing, Gemini is even weaker than GPT-4, Xiao noted.
This scenario of Google making comparisons to GPT-4 is similar to Chinese AI developers claiming their large models can also approach or exceed GPT-3.5 on certain metrics. In July, Chinese tech giant Baidu announced that a new version of its language model, Ernie Bot, also known as Wenxin YiYan 3.5, had surpassed ChatGPT-3.5 and on October 17, Wenxin YiYan 4.0 was released, once again, Baidu claimed it had an integrated capability equal to GPT-4, media reports said.
Latecomers can narrow the gap through active efforts, which could be the biggest revelation Chinese AI enterprises take away from Google releasing Gemini, Xiao said, recommending that domestic large model companies be firm in faith and strive to catch up.
As of October, China has more than 254 large-scale model manufacturers and universities with more than 1 billion parameters. These entities are spread across more than 20 provinces and regions, according to a latest white paper on the AI industry released by the Beijing Science and Technology Commission, Zhongguancun Science and Technology Park Management Committee.
AI focuses on attaining a sophisticated level of capability. Merely surpassing individual indicators does not necessarily mean declaring an absolute advantage for the opponent. Nevertheless, industry analysts noted that China's delay in the overall progress of LLMs can be compensated for by a competitive edge in new areas, such as models in more segmented industries, different scenario-based models and the seamless integration of language models with robots.
Liu Wei, director of the human-machine interaction and cognitive engineering laboratory with the Beijing University of Posts and Telecommunications, told the Global Times that "there is no way out if Chinese AI developers keep acting as followers of ChatGPT or Gemini. They must strive to promote basic and original technological breakthroughs such as large-model algorithms and frameworks so as to create product differentiation."
"Tourism exchanges between China and Pakistan hold immense significance for strengthening the [two countries'] bilateral relationship," Pakistani Ambassador to China Khalil Hashmi underscored on Wednesday at the opening ceremony of the Pakistan Pavilion at the 2023 China Outbound Travel and Tourism Market (COTTM) Expo in China National Agriculture Center.
The inauguration of the pavilion was part of a series of activities aimed at celebrating 2023 as the "Year of Tourism and Exchange" between Pakistan and China.
While commending the efforts of the exhibitors and tourism companies for the promotion of Pakistan's tourism potential, the ambassador noted that Pakistan was bestowed with rich cultural heritage, diverse landscapes and unique culinary delights. He encouraged Chinese tourists, academics, and entrepreneurs to visit Pakistan. There are different options for Chinese friends to explore Pakistan, Ambassador Hashmi told the Global Times on Wednesday.
People who are more interested in adventure tourism like mountain climbing or forest treks, for instance, will find that "Pakistan has some of the highest mountains in the world, So that's the very beautiful and very excellent regions for adventure tourism," he said.
Meanwhile, one of the many great attractions to Chinese tourists might be its civilization and heritage sites, Ambassador Hashmi added. One of the most visited sites in Pakistan, Taxila, is generally considered to be one of the most significant archaeological sites in Asia. Taxila was a university and educational center for Buddhists, and it attracted pilgrims from all across Asia.
Another attraction recommended by the ambassador to Chinese tourists was Pakistani gastronomy. "Chinese tourists would find Pakistani cuisine to be different and very diverse like in China. From the Northeast to the South, we also have places known for their spicy cuisine, a different type of spice than China, but we have less spicy food in the North. Food is a big industry in Pakistan and is something I'm sure our Chinese friends would also like," he told the Global Times.
The 2023 COTTM Expo focused on Belt and Road partner countries, saw the participation of more than 20 countries and regions such as Egypt, Pakistan, Kazakhstan, Saudi Arabia, Thailand, the Philippines, Poland, Tunisia, Seychelles, Tanzania, Azerbaijan, and others at the exhibition held from Wednesday to Friday, with invitations being extended to Chinese tourists to visit these countries to appreciate and experience their nature, history, humanities, and life.
At least 12 tourism exhibitors and companies from Pakistan participated in the Expo. Ambassador Hashmi expressed hope that COTTM would serve as an excellent platform for networking between the tourism companies in China and Pakistan, which would contribute toward the further enhancing of people-to-people exchanges between the two countries.
Huge cuts could be in store for federal science spending if President Donald Trump’s vision for fiscal year 2018 becomes reality.
Although details are skimpy, Trump’s $1.15 trillion budget proposal, released March 16, would make national security the top priority. The budget blueprint calls for a $54 billion increase in defense spending for 2018, offset by an equally big reduction in nondefense activities. Among the biggest science losers are the Environmental Protection Agency, which could see its budget shrink by 31 percent compared with 2017, and the National Institutes of Health, which faces an 18 percent spending slash. The Department of Energy’s Office of Science could lose about 17 percent of its funding while DOE’s Advanced Research Projects Agency-Energy, or ARPA-E — which supports research on promising energy technologies — faces complete elimination. The bare-bones budget blueprint leaves out figures altogether for many science-related agencies. It doesn’t even mention, for example, the National Science Foundation, a major source of federal funding for basic research across scientific disciplines. NSF is currently operating on a $7.5 billion budget. Full breakdowns aren’t available for most departments, so there’s no information on what’s to come for such programs as the National Institute of Standards and Technology (part of the Department of Commerce), the U.S. Fish and Wildlife Service (part of the Department of the Interior) and the Defense Advanced Research Projects Agency, or DARPA (part of the Department of Defense). More details for these and other omitted agencies may be included in a full budget proposal that the White House expects to release in May.
The White House’s budget outline is already raising alarm in the scientific community. “Major national goals are served by these investments in science and technology,” says Matt Hourihan, director of the R&D Budget and Policy Program at the American Association for the Advancement of Science in Washington, D.C. The proposed cuts, he says, “would set back our scientific leadership and would set back our technologies.” Ultimate authority of the budget rests with Congress. Last year, Congress failed to reach agreements on fiscal 2017 spending; the government has been operating under a continuing resolution that has largely kept agencies funded at their 2016 levels. That resolution expires April 28. But if the House and Senate can find common ground for fiscal 2018, which begins October 1, they are likely to be kinder to science than Trump was, Hourihan predicts. “Overall, Congress tends to find ways to support science and technology.”
Leland Cogliani, a lobbying consultant with Lewis-Burke Associates LLC in Washington, D.C., who specializes in DOE policy, agrees. “There’s a lot of angst and concern and worry about these proposed cuts to federal agencies as a whole,” he says. “My discussions with appropriators is that this budget is dead on arrival.” — Erin Wayman, with additional reporting from SN writers Environmental Protection Agency Trump’s proposed budget would devastate the EPA, dropping its annual budget from $8.2 billion to just $5.7 billion. The agency’s workforce would shed about 3,200 of its approximately 15,000 employees.
EPA’s scientific research arm would lose roughly half of its annual funding, dropping to about $250 million. Those cuts would threaten activities such as STAR grants, which provide research money and graduate fellowships in the environmental sciences.
“Unless we can find a backstop for those cuts from universities or the private sector, this is going to have a devastating impact on the global ability to do a lot of the basic science on environmental issues,” says Andrew Light of George Mason University in Fairfax, Va., a former senior adviser to the State Department’s U.S. Special Envoy for Climate Change.
In total, the budget blueprint targets more than 50 EPA programs for elimination, including the Energy Star program for boosting efficiency in appliances as well as restoration efforts to clean up the Great Lakes and Chesapeake Bay. — Thomas Sumner National Institutes of Health The president’s budget proposal would slash $5.8 billion from the $31.7 billion the NIH currently receives. Supporters of biomedical research call the proposal “disastrous” and say such deep cuts will topple the United States from its position as the world leader of biomedical research. “We’re not going to be No. 1 anymore. We’re going to slide down to the bottom of the pile,” says Jennifer Zeitzer, director of legislative relations at the Federation of American Societies for Experimental Biology, headquartered in Bethesda, Md.
Singled out in the budget proposal was the Fogarty International Center, which Trump wants to eliminate entirely. The center operates on a roughly $70 million budget and supports international collaboration for research and training in global health and infectious diseases.
“I think this is extraordinarily wrongheaded and dangerous,” says Chris Beyrer, an AIDS researcher at Johns Hopkins Bloomberg School of Public Health. Eliminating the center “is really a threat to the health and well-being of American people.” — Tina Hesman Saey Department of Energy DOE as a whole faces a 5.6 percent cut in Trump’s proposal, dropping it from $29.7 billion to $28 billion. The cut “falls disproportionately on the basic research and applied energy programs,” says Cogliani.
DOE’s Office of Science would lose about $900 million, coming from both cuts to the DOE and changing priorities for the agency. Currently funded at $5.3 billion, the Office of Science oversees 10 national labs and funds basic physics and energy research at over 300 schools in the United States.
Another DOE office, the Advanced Research Projects Agency-Energy, or ARPA-E, would get scrapped entirely. ARPA-E backs new energy technologies that show promise but aren’t far enough along to garner private sector funding. ARPA-E supports scientists working on nuclear fusion, for example, as well as new types of batteries.
One bright spot for the DOE is a call to increase funding of the National Nuclear Security Administration, which helps ensure the safety and efficacy of the U.S. nuclear weapons stockpile. — Laurel Hamers National Oceanic and Atmospheric Administration No specific budget request is included for NOAA, part of the Department of Commerce. NOAA, which monitors short- and long-term changes in the world’s oceans and atmosphere, is currently funded at $5.8 billion. The blueprint does, however, include targeted cuts that would eliminate more than $250 million for coastal and marine management, research and education. Those cuts include completely defunding NOAA’s $73 million Sea Grant program, which supports university-based research programs promoting the conservation and practical use of coastal and marine areas.
Other NOAA programs wouldn’t be hit as hard. The National Weather Service appears to avoid any major cuts, and the budget proposal maintains the development of current-generation weather satellites, including the Joint Polar Satellite System and the Geostationary Operational Environmental Satellite programs. — Thomas Sumner
NASA NASA’s proposed slice of the pie for fiscal 2018 is $19.1 billion — down 1 percent from 2017, before accounting for inflation.
“I think NASA’s top-line budget for 2018 is favorable,” says planetary scientist Alan Stern of the Southwest Research Institute in Boulder, Colo. “I bet there are many agency heads who would trade numbers with NASA in a heartbeat.”
The Trump administration plan is to refocus NASA’s priorities on “deep space exploration rather than Earth-centric research.” Planetary science research would see a boost from $1.6 billion to $1.9 billion, with continuing support for a Mars rover mission and an emphasis on exploring Jupiter’s moon Europa. The plan calls for a mission to repeatedly fly by Europa but does not provide funds for a mission to land on the Jovian moon and possibly penetrate its ice (SN: 5/17/15, p. 20).
The White House appears to be committed to human exploration of deep space, at least in part. With $3.7 billion, engineers and scientists can continue to build the Orion crew vehicle and Space Launch System, which is supposed to support a human journey to Mars. The plan, however, eliminates the multibillion-dollar Asteroid Redirect Mission, which would bring a boulder from an asteroid into the moon’s orbit and send astronauts to explore it around 2025.
Cuts would also be made to NASA’s earth science program. The White House proposes to eliminate four earth science missions: PACE, the Plankton, Aerosol, Cloud, ocean Ecosystem mission; OCO-3, the Orbiting Carbon Observatory–3 mission; DSCOVR, the Deep Space Climate Observatory; and a pathfinder mission for CLARREO, the Climate Absolute Radiance and Refractivity Observatory.
NASA’s Office of Education, with its estimated price tag of $115 million, would also be eliminated. — Ashley Yeager U.S. Geological Survey Last year the USGS was funded at about $1.1 billion; under the White House’s proposed budget, USGS would receive “more than $900 million,” though just how much more remains unclear. The amount includes funding for “research and data collection that informs sustainable energy development, responsible resource management, and natural hazard risk reduction.”
“The budget is vague, but what I can say is that overall what we’re seeing is very alarming and very disheartening,” says Christine McEntee, executive director and CEO of the American Geophysical Union in Washington, D.C. — Thomas Sumner U.S. Centers for Disease Control and Prevention No one can say exactly how the CDC fares in the proposed budget, which mentions the public health agency only once and offers no funding total. The CDC’s 2017 funding level included about $6.3 billion in appropriated funds.
President Trump’s budget proposes a “new Federal Emergency Response Fund” to respond to outbreaks such as Zika, but there’s no mention of how much money this fund would include, or which agencies would actually receive it.
Only one specific figure in the budget pertains to the CDC directly: a $500 million block grant “to increase State flexibility and focus on the leading public health challenges specific to each State.”
“500 million sounds like a lot of money, but is that over 10 years, five years, or what?” asks Karen Goraleski, executive director of the American Society of Tropical Medicine and Hygiene in Oakbrook Terrace, Ill. “With no details whatsoever, it’s anybody’s guess where the money will go, and what’s being cut in order to pay for this.” — Meghan Rosen U.S. Food and Drug Administration User fees that companies pay to the FDA to review medical products would increase to “over $2 billion in 2018,” approximately double 2017 levels, according to the budget proposal. Along with an unspecified “package of administrative actions,” the extra money could help “speed the development of safe and effective medical products.”
More money is good but isn’t likely to do much to move products along, says Jeff Allen, president and CEO of Friends of Cancer Research, an advocacy group. “The review process is just a fraction of the amount of time it takes for a new drug to reach the market,” he says.
The budget request glossed over the main source of FDA dollars, taxpayer money appropriated by Congress. The agency currently receives $2.72 billion in appropriated funds, nearly $1 billion in medical product user fees and almost another $1 billion in user fees for other products.
Unlike appropriated funds, user fees can be used only for specifically defined activities, like reviewing product applications. Without naming a number for appropriated funds, the fate of many FDA programs, including food safety, remain in the dark. And expecting the FDA to function mainly on user fees “seems rather unrealistic and totally unfeasible,” Allen says. — Meghan Rosen
When choosing more attractive guys, girl guppies with larger brains have an advantage over their smaller-brained counterparts. But there’s a cost to such brainpower, and that might help explain one of the persistent mysteries of sex appeal, researchers report March 22 in Science Advances.
One sex often shows a strong preference for some trait in the other, whether it’s a longer fish fin or a more elaborate song and dance. Yet after millions of years, there’s still variety in many animals’ color, size, shape or song, says study coauthor Alberto Corral-López, an evolutionary biologist at Stockholm University. Somehow generations of mate choice have failed to make the opposite sex entirely fabulous.
Mate choice could require a certain amount of brainpower, with animals weighing the appeal of suitors and choosing among them. Previous research suggests a smaller brain dims guppies’ mental abilities, and the researchers wondered how brain size might affect the fish’s choice of mate.
To test the idea, researchers used female guppies bred for either a larger or smaller brain. Guppy brains are tiny to begin with, but after five generations of breeding the brain sizes in the study differed by about 13 percent, within the range of what biologists find in the wild. Each female was offered a choice between a colorful male with orange spots and a bigger tail versus a drab male of about the same weight but without much glory behind. The male fish were installed in compartments at either end of a tank, and females swam back and forth, forced to remember and mentally compare one suitor with his rival.
Females with larger brains showed a preference overall for the more colorful male. Smaller-brained females showed no preference. (The difference did not come from differences in color vision, Corral-López says. The researchers checked the eye genes of the fish and also tested their ability to distinguish colors.)
Interest in flashy-looking males may not be just a fashion choice for females. Orange colors come from pigments in food, suggesting that brighter males may be better fed and healthier, which could lead to healthier offspring. And more colorful males are typically better at finding food. Corral-López also tested females that had not been specially bred for brain size, and these fish preferred the colorful males, too.
But bigger-brained females did not beat their small-brained compatriots in all tests. The smaller-brained guppies tended to grow faster when they were young and to have better immune systems and more offspring.
Thus, circumstances might tip the balance toward or against braininess, the researchers say. Having more babies might be more useful than a discriminating brain, for instance, when food is plentiful and most males manage a decent orange. Such changes in fortune might help explain how variety in appearance persists despite strong mating preferences, Corral-López and colleagues argue. Sometimes flashier males win females, but sometimes drab is just fine.
“Exciting work,” says Molly Cummings of the University of Texas at Austin, who studies fish brains and sexual selection. Checking the fish’s vision was especially important, she says. The results show that females were not “simple slaves to their sensory system.”
The new paper, of course, tracked lab animals, and there’s little data on what differences in brain size mean for mate choice in the wild, says evolutionary biologist Kimberly Hughes of Florida State University in Tallahassee. The new guppy study suggests it’s certainly worth looking at what girl guppies do naturally, she says.
WASHINGTON — Immune cells engineered to hunt and destroy cancer cells may help some people with acute lymphoblastic leukemia (ALL) live much longer.
Outcomes depended upon disease severity before treatment, oncologist Jae Park reported April 3 at the American Association for Cancer Research annual meeting.
In ALL — expected to strike 5,970 people and kill 1,440 in the United States in 2017 — immune cells called B cells grow out of control in bone marrow and can spread to other tissues. Overall, five-year survival rates are 71 percent. But fewer than 10 percent of people survive for five years after a relapse of the cancer, said Park of Memorial Sloan Kettering Cancer Center in New York City. Park and colleagues genetically engineered T cells from 51 people whose leukemia came back or who didn’t respond to initial chemotherapy. These CAR-T cells seek out and kill the rogue B cells.
Of 20 people who started the study with leukemia cells making up less than 5 percent of their bone marrow, 95 percent had a complete response to the CAR-T treatment. Most are still alive with no signs of leukemia; one patient remains in remission five years after treatment.
But 31 people who started immune therapy with leukemia cells composing more than 5 percent of their bone marrow didn’t fare as well. After good initial responses, the cancer came back a median of 6.3 months later. Patients survived a median of 17 months, although some are still alive after three years.
The second group also tended to have more severe side effects, including an immune reaction called cytokine release syndrome and neurotoxicity, or nerve problems.
Park and his colleagues are not yet sure why the therapy works better for some people than others. But, he said, CAR-T cell therapy “still provides better survival than traditional treatments.”
DENVER — An invasive beetle has unexpected — and potentially troublesome — tastes in trees. Now two new studies are clarifying the insects’ dining habits, researchers reported at the annual Entomological Society of America meeting.
Metallic-green Asian beetles called emerald ash borers (Agrilus planipennis) have devastated wide swaths of forest in North America. For years, researchers believed that only various kinds of ash trees were at risk. But in 2014, researchers noticed infestations in white fringe trees (Chionanthus virginicus), a multi-stemmed tree native to the southeastern United States with flowers like a cluster of streamers. And after looking at trees related to ashes, researchers reported lab evidence in 2017 that the beetle larvae can grow to adulthood in the Manzanilla variety of commercial olive trees (Olea europaea). Whether the beetle poses a serious or slight risk to the overlooked targets is still being researched. Emerald ash borers, accidentally imported probably in wood packing materials during the 1980s or 1990s, have killed hundreds of millions of ash trees in 31 states and two Canadian provinces. Larvae chewing tunnels through trees’ internal nutrient channels can doom a tree. It’s “a major, major pest,” says entomologist Jackie Hoban of the University of Maryland in College Park. “It’s so sad — you see entire patches of trees just dead.” Lab tests of the recently discovered threat to olive trees show that adult borers don’t eat as much of these leaves as they do of ash leaves, forest entomologist Donnie Peterson of Wright State University in Dayton, Ohio, reported November 6 at the meeting. These adults also die prematurely if those leaves are the only food option. But adult borers’ distaste for this variety of olive doesn’t yet mean the trees are safe. Female beetles feeding on ash trees might, in theory, fly to a nearby olive to lay eggs. To compare beetles’ preferences for laying eggs on olive versus ash will take a larger study. But Peterson’s first results are a little worrying. When he put olives and green ashes in a known infested zone, one of the few eggs he found was on an olive tree.
Free-flying beetles do lay eggs on white fringe trees, attacks that long went unreported. But the trees may not be as healthful a feeding site for beetle larvae as ash trees. In indoor tests, fewer larvae survived to their later stages on the fringe trees compared with larvae on white ashes, David Olson of the University of Kentucky in Lexington reported November 5. Olson works on whether biocontrol strategies developed for ash trees might also work on white fringe trees. So far, it doesn’t look encouraging. In outdoor tests, the most successful of four tiny parasitic wasp species released in North America did what they’re supposed to: Tetrastichus planipennisi doomed some beetle larvae in ash trees by using the youngsters as living food for baby wasps. Beetle larvae in nearby fringe trees, however, escaped wasp attacks.
Even if fringe trees don’t turn out to suffer massive damage, they could still present a very real threat if nurseries shipping trees from infested areas accidentally transport beetle larvae, too, Hoban says. Besides spreading the pests, that could make it tougher for ashes to weather existing invasions. The hope for ashes is that wasps will help keep beetles in check, and some exceptional ash trees will prove resistant enough to rebuild some sort of population.
Editor’s note: This story was updated November 23 to change the photo at the top of the story. The original photo was not an emerald ash borer.
There’s so much water on some of TRAPPIST-1’s seven Earth-sized planets that any life lurking there might be difficult to detect.
New estimates of the makeup of these potentially habitable worlds suggests that two of them are more than half water, by mass, researchers report March 19 in Nature Astronomy. Earth, by comparison, is less than 0.1 percent water.
TRAPPIST-1’s planets are so wet that most of the water probably isn’t even liquid, but ice formed under high pressure, says Cayman Unterborn, an exogeologist at Arizona State University in Tempe. That would change the chemistry happening on the planet in a way that could make any signs of life tricky to distinguish from geochemical processes. TRAPPIST-1 is a cool, dim star about 39 light-years from Earth. Since the star system’s discovery in 2017, it’s been a prime focus for scientists seeking life outside of our solar system because some of the seven planets might have the right conditions to host life (SN: 12/23/17, p. 25). They’re rocky rather than gaseous, and at least three are at a distance from the star that could let them host liquid water.
Unterborn and his colleagues used previous estimates of the mass and diameter of TRAPPIST-1’s planets to calculate the worlds’ densities. Then, the team used a computer program to test different compositions of basic planetary building blocks to determine which makeups would yield planets with those densities. Frozen or liquid water is less dense than rock, but more dense than a gas. So a less dense planet might have a higher proportion of water or gases compared with a denser, rockier world. But Unterborn doesn’t think the TRAPPIST-1 planets are massive enough to hold onto much of an atmosphere — it would probably escape into space. So the team concluded the lower densities in this system probably come from the presence of water. The researchers focused on four of the seven planets for which they had the best data. The first and second planets from the dwarf star are probably less than 15 percent water by mass, still far wetter than Earth, the researchers found.
The fifth and sixth planets, both in the habitable zone, are more than half water — a volume so large that the water pressure alone could force much of it into a form of ice, Unterborn says. He estimates that on the fifth planet, TRAPPIST-1f, liquid water extends down about 200 kilometers — about 20 times deeper than the Mariana Trench on Earth. Below that, a nearly 2,300-kilometer layer of ice stretches almost halfway to the center of the planet.
These water estimates might throw a wet blanket on the chances of finding life on any of TRAPPIST-1’s planets, if it exists at all. The thick covering of ice and water might mess up some of the geological processes that, at least on Earth, help regulate the planet’s temperature over long periods of time. If so, that might be an impediment to life getting a foothold. Having so much water might also slow or halt the movement of building blocks of life, such as carbon and phosphorus (the backbone of DNA), into oceans. That could make it harder for us to detect whether certain molecules in the water are hints of the presence of living organisms, or just the by-products of geological processes.
It doesn’t rule out life, Unterborn says, but it does make it harder to find. When it comes to understanding the way a planet’s geologic composition affects chemical processes, “the vast majority of data that’s out there is for one planet, and it’s ours,” he says. The TRAPPIST-1 system is “such an extreme of rocky planet chemistry.”
Updated estimates of the TRAPPIST-1 planets’ masses were published in February (SN Online: 2/5/18), and this study doesn’t use those numbers, says Billy Quarles, a physicist at the University of Oklahoma in Norman who wasn’t part of the study. Based on the newer estimates, TRAPPIST-1’s planets aren’t quite as wet as this study predicts. But the big-picture conclusion — that some of the planets contain far more water than Earth — still holds up, he says.
An ancient hominid dubbed Homo naledi may have lit controlled fires in the pitch-dark chambers of an underground cave system, new discoveries hint.
Researchers have found remnants of small fireplaces and sooty wall and ceiling smudges in passages and chambers throughout South Africa’s Rising Star cave complex, paleoanthropologist Lee Berger announced in a December 1 lecture hosted by the Carnegie Institution of Science in Washington, D.C.
“Signs of fire use are everywhere in this cave system,” said Berger, of the University of the Witwatersrand, Johannesburg.
H. naledi presumably lit the blazes in the caves since remains of no other hominids have turned up there, the team says. But the researchers have yet to date the age of the fire remains. And researchers outside Berger’s group have yet to evaluate the new finds.
H. naledi fossils date to between 335,000 and 236,000 years ago (SN: 5/9/17), around the time Homo sapiens originated (SN: 6/7/17). Many researchers suspect that regular use of fire by hominids for light, warmth and cooking began roughly 400,000 years ago (SN: 4/2/12).
Such behavior has not been attributed to H. naledi before, largely because of its small brain. But it’s now clear that a brain roughly one-third the size of human brains today still enabled H. naledi to achieve control of fire, Berger contends.
Last August, Berger climbed down a narrow shaft and examined two underground chambers where H. naledi fossils had been found. He noticed stalactites and thin rock sheets that had partly grown over older ceiling surfaces. Those surfaces displayed blackened, burned areas and were also dotted by what appeared to be soot particles, Berger said.
Meanwhile, expedition codirector and Wits paleoanthropologist Keneiloe Molopyane led excavations of a nearby cave chamber. There, the researchers uncovered two small fireplaces containing charred bits of wood, and burned bones of antelopes and other animals. Remains of a fireplace and nearby burned animal bones were then discovered in a more remote cave chamber where H. naledi fossils have been found.
Still, the main challenge for investigators will be to date the burned wood and bones and other fire remains from the Rising Star chambers and demonstrate that the fireplaces there come from the same sediment layers as H. naledi fossils, says paleoanthropologist W. Andrew Barr of George Washington University in Washington, D.C., who wasn’t involved in the work.
“That’s an absolutely critical first step before it will be possible to speculate about who may have made fires for what reason,” Barr says.
The glossy leaves and branching roots of mangroves are downright eye-catching, and now a study finds that the moon plays a special role in the vigor of these trees.
Long-term tidal cycles set in motion by the moon drive, in large part, the expansion and contraction of mangrove forests in Australia, researchers report in the Sept. 16 Science Advances. This discovery is key to predicting when stands of mangroves, which are good at sequestering carbon and could help fight climate change, are most likely to proliferate (SN: 11/18/21). Such knowledge could inform efforts to protect and restore the forests. Mangroves are coastal trees that provide habitat for fish and buffer against erosion (SN: 9/14/22). But in some places, the forests face a range of threats, including coastal development, pollution and land clearing for agriculture. To get a bird’s-eye view of these forests, Neil Saintilan, an environmental scientist at Macquarie University in Sydney, and his colleagues turned to satellite imagery. Using NASA and U.S. Geological Survey Landsat data from 1987 to 2020, the researchers calculated how the size and density of mangrove forests across Australia changed over time.
After accounting for persistent increases in these trees’ growth — probably due to rising carbon dioxide levels, higher sea levels and increasing air temperatures — Saintilan and his colleagues noticed a curious pattern. Mangrove forests tended to expand and contract in both extent and canopy cover in a predictable manner. “I saw this 18-year oscillation,” Saintilan says.
That regularity got the researchers thinking about the moon. Earth’s nearest celestial neighbor has long been known to help drive the tides, which deliver water and necessary nutrients to mangroves. A rhythm called the lunar nodal cycle could explain the mangroves’ growth pattern, the team hypothesized.
Over the course of 18.6 years, the plane of the moon’s orbit around Earth slowly tips. When the moon’s orbit is the least tilted relative to our planet’s equator, semidiurnal tides — which consist of two high and two low tides each day — tend to have a larger range. That means that in areas that experience semidiurnal tides, higher high tides and lower low tides are generally more likely. The effect is caused by the angle at which the moon tugs gravitationally on the Earth.
Saintilan and his colleagues found that mangrove forests experiencing semidiurnal tides tended to be larger and denser precisely when higher high tides were expected based on the moon’s orbit. The effect even seemed to outweigh other climatic drivers of mangrove growth, such as El Niño conditions. Other regions with mangroves, such as Vietnam and Indonesia, probably experience the same long-term trends, the team suggests.
Having access to data stretching back decades was key to this discovery, Saintilan says. “We’ve never really picked up before some of these longer-term drivers of vegetation dynamics.”
It’s important to recognize this effect on mangrove populations, says Octavio Aburto-Oropeza, a marine ecologist at the Scripps Institution of Oceanography in La Jolla, Calif., who was not involved in the research.
Scientists now know when some mangroves are particularly likely to flourish and should make an extra effort at those times to promote the growth of these carbon-sequestering trees, Aburto-Oropeza says. That might look like added limitations on human activity nearby that could harm the forests, he says. “We should be more proactive.”
Cocooned within the bowels of the Earth, one mineral’s metamorphosis into another may trigger some of the deepest earthquakes ever detected.
These cryptic tremors — known as deep-focus earthquakes — are a seismic conundrum. They violently rupture at depths greater than 300 kilometers, where intense temperatures and pressures are thought to force rocks to flow smoothly. Now, experiments suggest that those same hellish conditions might also sometimes transform olivine — the primary mineral in Earth’s mantle — into the mineral wadsleyite. This mineral switch-up can destabilize the surrounding rock, enabling earthquakes at otherwise impossible depths, mineral physicist Tomohiro Ohuchi and colleagues report September 15 in Nature Communications. “It’s been a real puzzle for many scientists because earthquakes shouldn’t occur deeper than 300 kilometers,” says Ohuchi, of Ehime University in Matsuyama, Japan.
Deep-focus earthquakes usually occur at subduction zones where tectonic plates made of oceanic crust — rich in olivine — plunge toward the mantle (SN: 1/13/21). Since the quakes’ seismic waves lose strength during their long ascent to the surface, they aren’t typically dangerous. But that doesn’t mean the quakes aren’t sometimes powerful. In 2013, a magnitude 8.3 deep-focus quake struck around 609 kilometers below the Sea of Okhotsk, just off Russia’s eastern coast.
Past studies hinted that unstable olivine crystals could spawn deep quakes. But those studies tested other minerals that were similar in composition to olivine but deform at lower pressures, Ohuchi says, or the experiments didn’t strain samples enough to form faults.
He and his team decided to put olivine itself to the test. To replicate conditions deep underground, the researchers heated and squeezed olivine crystals up to nearly 1100° Celsius and 17 gigapascals. Then the team used a mechanical press to further compress the olivine slowly and monitored the deformation.
From 11 to 17 gigapascals and about 800° to 900° C, the olivine recrystallized into thin layers containing new wadsleyite and smaller olivine grains. The researchers also found tiny faults and recorded bursts of sound waves — indicative of miniature earthquakes. Along subducting tectonic plates, many of these thin layers grow and link to form weak regions in the rock, upon which faults and earthquakes can initiate, the researchers suggest.
“The transformation really wreaks havoc with the [rock’s] mechanical stability,” says geophysicist Pamela Burnley of the University of Nevada, Las Vegas, who was not involved in the research. The findings help confirm that olivine transformations are enabling deep-focus earthquakes, she says.
Next, Ohuchi’s team plans to experiment on olivine at even higher pressures to gain insights into the mineral’s deformation at greater depths.
