Our modern lives depend on rare earth elements, and someday soon we may not have enough to meet growing demand.
Because of their special properties , these 17 metallic elements are crucial ingredients in computer screens, cell phones and other electronics, compact fluorescent lamps, medical imaging machines, lasers, fiber optics, pigments, polishing powders, industrial catalysts – the list goes on and on ( SN Online: 1/16/23 ). Notably rare earths are an essential part of the high-powered magnets and rechargeable batteries in the electric vehicles and renewable energy technologies needed to get the world to a low- or zero-carbon future.
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In 2021, the world mined 280,000 metric tons of rare earths — roughly 32 times as much as was mined in the mid-1950s. And demand is only going to increase. By 2040, experts estimate, we’ll need up to seven times as much rare earths as we do today.
Satisfying that appetite won’t be easy. Rare earth elements are not found in concentrated deposits. Miners must excavate huge amounts of ore, subject it to physical and chemical processes to concentrate the rare earths, and then separate them. The transformation is energy intensive and dirty, requiring toxic chemicals and often generating a small amount of radioactive waste that must be safely disposed of. Another concern is access: China has a near monopoly on both mining and processing; the United States has just one active mine ( SN Online: 1/1/23 ).
For most of the jobs rare earths do, there are no good substitutes. So to help meet future demand and diversify who controls the supply — and perhaps even make rare earth recovery “greener” — researchers are looking for alternatives to conventional mining.
Proposals include everything from extracting the metals from coal waste to really out-there ideas like mining the moon. But the approach most likely to make an immediate dent is recycling. “Recycling is going to play a very important and central role,” says Ikenna Nlebedim, a materials scientist at Ames National Laboratory in Iowa and the Department of Energy’s Critical Materials Institute. “That’s not to say we’re going to recycle our way out of the critical materials challenge.”
Still, in the rare earth magnets market, for instance, by about 10 years from now, recycling could satisfy as much as a quarter of the demand for rare earths, based on some estimates. “That’s huge,” he says.
But before the rare earths in an old laptop can be recycled as regularly as the aluminum in an empty soda can, there are technological, economic and logistical obstacles to overcome.
Recycling seems like an obvious way to get more rare earths. It’s standard practice in the United States and Europe to recycle from 15 to 70 percent of other metals, such as iron, copper, aluminum, nickel and tin. Yet today, only about 1 percent of rare earth elements in old products are recycled, says Simon Jowitt, an economic geologist at the University of Nevada, Las Vegas.
“Copper wiring can be recycled into more copper wiring. Steel can just be recycled into more steel,” he says. But a lot of rare earth products are “inherently not very recyclable.”
Rare earths are often blended with other metals in touch screens and similar products, making removal difficult. In some ways, recycling rare earths from tossed-out items resembles the challenge of extracting them from ore and separating them from each other. Traditional rare earth recycling methods also require hazardous chemicals such as hydrochloric acid and a lot of heat, and thus a lot of energy. On top of the environmental footprint, the cost of recovery may not be worth the effort given the small yield of rare earths. A hard disk drive, for instance, might contain just a few grams; some products offer just milligrams.
Chemists and materials scientists, though, are trying to develop smarter recycling approaches. Their techniques put microbes to work, ditch the acids of traditional methods or attempt to bypass extraction and separation.
One approach leans on microscopic partners. Gluconobacter bacteria naturally produce organic acids that can pull rare earths, such as lanthanum and cerium, from spent catalysts used in petroleum refining or from fluorescent phosphors used in lighting. The bacterial acids are less environmentally harmful than hydrochloric acid or other traditional metal-leaching acids, says Yoshiko Fujita, a biogeochemist at Idaho National Laboratory in Idaho Falls. Fujita leads research into reuse and recycling at the Critical Materials Institute. “They can also be degraded naturally,” she says.
In experiments, the bacterial acids can recover only about a quarter to half of the rare earths from spent catalysts and phosphors. Hydrochloric acid can do much better — in some cases extracting as much as 99 percent. But bio-based leaching might still be profitable , Fujita and colleagues reported in 2019 in ACS Sustainable Chemistry & Engineering .
In a hypothetical plant recycling 19,000 metric tons of used catalyst a year, the team estimated annual revenues to be roughly $1.75 million. But feeding the bacteria that produce the acid on-site is a big expense. In a scenario in which the bacteria are fed refined sugar, total costs for producing the rare earths are roughly $1.6 million a year, leaving around just $150,000 in profits. Switching from sugar to corn stalks, husks and other harvest leftovers, however, would slash costs by about $500,000, raising profits to about $650,000.
Other microbes can also help extract rare earths and take them even further. A few years ago, researchers discovered that some bacteria that metabolize rare earths produce a protein that preferentially grabs onto these metals. This protein, lanmodulin, can separate rare earths from each other, such as neodymium from dysprosium — two components of rare earth magnets. A lanmodulin-based system might eliminate the need for the many chemical solvents typically used in such separation. And the waste left behind — the protein — would be biodegradable. But whether the system will pan out on a commercial scale is unknown.
Another approach already being commercialized skips the acids and uses copper salts to pull the rare earths from discarded magnets, a valuable target. Neodymium-iron-boron magnets are about 30 percent rare earth by weight and the single largest application of the metals in the world. One projection suggests that recovering the neodymium in magnets from U.S. hard disk drives alone could meet up about 5 percent of the world’s demand outside of China before the end of the decade.
Nlebedim led a team that developed a technique that uses copper salts to leach rare earths out of shredded electronic waste that contains magnets. Dunking the e-waste in a copper salt solution at room temperature dissolves the rare earths in the magnets. Other metals can be scooped out for their own recycling, and the copper can be reused to make more salt solution. Next, the rare earths are solidified and, with the help of additional chemicals and heating, transformed into powdered minerals called rare earth oxides. The process, which has also been used on material left over from magnet manufacturing that typically goes to waste, can recover 90 to 98 percent of the rare earths, and the material is pure enough to make new magnets, Nlebedim’s team has demonstrated.
In a best-case scenario, using this method to recycle 100 tons of leftover magnet material might produce 32 tons of rare earth oxides and net more than $1 million in profits, an economic analysis of the method suggests.
That study also evaluated the approach’s environmental impacts. Compared with producing one kilogram of rare earth oxide via one of the main types of mining and processing currently used in China, the copper salt method has less than half the carbon footprint . It produces an average of about 50 kilograms of carbon dioxide equivalent per kilogram of rare earth oxide versus 110, Nlebedim’s team reported in 2021 in ACS Sustainable Chemistry & Engineering .
Rare earths make smartphones and other tech possible but pose big challenges. Read more from this series:
But it’s not necessarily greener than all forms of mining. One sticking point is that the process requires toxic ammonium hydroxide and roasting, which consumes a lot of energy, and it still releases some carbon dioxide. Nlebedim’s group is now tweaking the technique. “We want to decarbonize the process and make it safer,” he says.
Meanwhile, the technology seems promising enough that TdVib, an Iowa company that designs and manufactures magnetic materials and products, has licensed it and built a pilot plant. The initial aim is to produce two tons of rare earth oxides per month, says Daniel Bina, TdVib’s president and CEO. The plant will recycle rare earths from old hard disk drives from data centers.
Noveon Magnetics, a company in San Marcos, Texas, is already making recycled neodymium-iron-boron magnets. In typical magnet manufacturing, the rare earths are mined, transformed into metal alloys, milled into a fine powder, magnetized and formed into a magnet. Noveon knocks out those first two steps, says company CEO Scott Dunn.
After demagnetizing and cleaning discarded magnets, Noveon directly mills them into a powder before building them back up as new magnets. Unlike with other recycling methods, there’s no need to extract and separate the rare earths out first. The final product can be more than 99 percent recycled magnet, Dunn says, with a small addition of virgin rare earth elements — the “secret sauce,” as he puts it — that allows the company to fine-tune the magnets’ attributes.
Compared with traditional magnet mining and manufacturing, Noveon’s method cuts energy use by about 90 percent , Miha Zakotnik, Noveon’s chief technology officer, and other researchers reported in 2016 in Environmental Technology & Innovation . Another 2016 analysis estimated that for every kilogram of magnet produced via Noveon’s method, about 12 kilograms of carbon dioxide equivalent are emitted. That’s about half as much of the greenhouse gas as conventional magnets .
Dunn declined to share what volume of magnets Noveon currently produces or how much its magnets cost. But the magnets are being used in some industrial applications, for pumps, fans and compressors, as well as some consumer power tools and other electronics.
Even as researchers clear technological hurdles, there are still logistical barriers to recycling. “We don’t have the systems for collecting end-of-life products that have rare earths in them,” Fujita says, “and there’s the cost of dismantling those products.” For a lot of e-waste, before rare earth recycling can begin, you have to get to the bits that contain those precious metals.
Noveon has a semiautomated process for removing magnets from hard disk drives and other electronics.
Apple is also trying to automate the recycling process. The company’s Daisy robot can dismantle iPhones. And in 2022, Apple announced a pair of robots called Taz and Dave that facilitate the recycling of rare earths. Taz can gather magnet-containing modules that are typically lost during the shredding of electronics. Dave can recover magnets from taptic engines, Apple’s technology for providing users with tactile feedback when, say, tapping an iPhone screen.
Even with robotic aids, it would still be a lot easier if companies just designed products in a way that made recycling easy, Fujita says.
No matter how good recycling gets, Jowitt sees no getting around the need to ramp up mining to feed our rare earth–hungry society. But he agrees recycling is necessary. “We’re dealing with intrinsically finite resources,” he says. “Better we try and extract what we can rather than just dumping it in the landfill.”
Erin Wayman is the magazine managing editor. She has a master’s degree in biological anthropology from the University of California, Davis and a master’s degree in science writing from Johns Hopkins University.
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Coal mining can pollute nearby waterways, creating acidic water rich in heavy metals. Researchers are looking to tap such acid mine drainage (like that shown in western Pennsylvania) for rare earth elements.
In Appalachia’s coal country, researchers envision turning toxic waste into treasure. The pollution left behind by abandoned mines is an untapped source of rare earth elements.
Rare earths are a valuable set of 17 elements needed to make everything from smartphones and electric vehicles to fluorescent bulbs and lasers. With global demand skyrocketing and China having a near-monopoly on rare earth production — the United States has only one active mine — there’s a lot of interest in finding alternative sources, such as ramping up recycling .
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Pulling rare earths from coal waste offers a two-for-one deal: By retrieving the metals, you also help clean up the pollution.
Long after a coal mine closes, it can leave a dirty legacy. When some of the rock left over from mining is exposed to air and water, sulfuric acid forms and pulls heavy metals from the rock. This acidic soup can pollute waterways and harm wildlife.
Recovering rare earths from what’s called acid mine drainage won’t single-handedly satisfy rising demand for the metals, acknowledges Paul Ziemkiewicz, director of the West Virginia Water Research Institute in Morgantown. But he points to several benefits.
Unlike ore dug from typical rare earth mines, the drainage is rich with the most-needed rare earth elements. Plus, extraction from acid mine drainage also doesn’t generate the radioactive waste that’s typically a by-product of rare earth mines, which often contain uranium and thorium alongside the rare earths. And from a practical standpoint, existing facilities to treat acid mine drainage could be used to collect the rare earths for processing. “Theoretically, you could start producing tomorrow,” Ziemkiewicz says.
From a few hundred sites already treating acid mine drainage, nearly 600 metric tons of rare earth elements and cobalt — another in-demand metal — could be produced annually, Ziemkiewicz and colleagues estimate.
Currently, a pilot project in West Virginia is taking material recovered from an acid mine drainage treatment site and extracting and concentrating the rare earths.
If such a scheme proves feasible, Ziemkiewicz envisions a future in which cleanup sites send their rare earth hauls to a central facility to be processed, and the elements separated. Economic analyses suggest this wouldn’t be a get-rich scheme. But, he says, it could be enough to cover the costs of treating the acid mine drainage.
Erin Wayman is the magazine managing editor. She has a master’s degree in biological anthropology from the University of California, Davis and a master’s degree in science writing from Johns Hopkins University.
Our mission is to provide accurate, engaging news of science to the public. That mission has never been more important than it is today.
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Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
A crucial link in the life cycle of one parasitic plant may be found in a surprising place — the bellies of the descendants of an ancient line of rabbits.
Given their propensity for nibbling on gardens and darting across suburban lawns, it can be easy to forget that rabbits are wild animals. But a living reminder of their wildness can be found on two of Japan’s Ryukyu Islands, if you have the patience to look for it: the endangered Amami rabbit, a “living fossil” that looks strikingly similar to ancient Asian rabbits.
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One estimate suggests there are fewer than 5,000 of the animals left in the wild. The lives of Amamis ( Pentalagus furnessi ) are shrouded in mystery due to their rarity, but they seem to play a surprising ecological role as seed dispersers , researchers report January 23 in Ecology .
Seed dispersal is the main point in a plant’s life cycle when it can move to a new location ( SN: 11/14/22 ). So dispersal is crucially important for understanding how plant populations are maintained and how species will respond to climate change, says Haldre Rogers, a biologist at Virginia Tech in Blacksburg, who was not involved with the study. Despite this, seed dispersal hasn’t received much attention, she says. “We don’t know what disperses the seeds of most plants in the world.”
Locals from the Ryukyu Islands were the first to notice that the “iconic yet endangered” Amami rabbit was nibbling on the fruit of another local species, the plant Balanophora yuwanensis , says Kenji Suetsugu, a biologist at Kobe University in Japan.
Rabbits generally like to eat vegetative tissue from plants, like leaves and stems, and so haven’t been thought to contribute much to spreading seeds, which are often housed in fleshy fruits.
To confirm what the locals reported, Suetsugu and graduate student Hiromu Hashiwaki set up camera traps around the island to catch the rabbits in the act. The researchers were able to record rabbits munching on Balanophora fruits 11 times, but still needed to check whether the seeds survived their trip through the bunny tummies.
So the team headed out to the subtropical islands and scooped up rabbit poop, finding Balanophora seeds inside that could still be grown. By swallowing the seeds and pooping them out elsewhere, the Amami rabbits were clearly acting as seed dispersers.
Balanophora plants are parasitic and don’t have chlorophyll, so they can’t use photosynthesis to make food of their own ( SN: 3/2/17 ). Instead, they suck energy away from a host plant. This means where their seeds end up matters, and the Amami rabbits “may facilitate the placement of seeds near the roots of a compatible host” by pooping in underground burrows, Suetsugu says. “Thus, the rabbits likely provide a crucial link between Balanophora and its hosts” that remains to be further explored, he says.
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Understanding the ecology of an endangered species like the Amami rabbit can help with conserving both it and the plants that depend on it.
An animal need not be in obvious peril for a change in its number to affect seed dispersal, with potentially negative consequences for the ecosystem. For example, “we think of robins as super common … but they’ve declined a lot in the last 50 years,” Rogers says. “Half as many robins means half as many seeds are getting moved around, even though no one’s worried about robins as a conservation issue.”
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Your support enables us to keep our content free and accessible to the next generation of scientists and engineers. Invest in quality science journalism by donating today.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
Scientists have proposed that Earth’s solid inner core (yellow in this diagram) rotates faster than the rest of Earth. A new study suggests the core’s rotation has recently paused, and is reversing direction.
Earth’s inner core may have temporarily stopped rotating relative to the mantle and surface, researchers report in the January 23 Nature Geoscience . Now, the direction of the inner core’s rotation may be reversing — part of what could be a roughly 70-year-long cycle that may influence the length of Earth’s days and its magnetic field — though some researchers are skeptical.
“We see strong evidence that the inner core has been rotating faster than the surface, [but] by around 2009 it nearly stopped,” says geophysicist Xiaodong Song of Peking University in Beijing. “Now it is gradually mov[ing] in the opposite direction.”
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Such a profound turnaround might sound bizarre, but Earth is volatile ( SN: 1/13/21 ). Bore through the ever-shifting crust and you’ll enter the titanic mantle , where behemoth masses of rock flow viscously over spans of millions of years, sometimes upwelling to excoriate the overlying crust ( SN: 1/11/17, SN: 3/2/17, SN: 2/4/21 ). Delve deeper and you’ll reach Earth’s liquid outer core. Here, circulating currents of molten metals conjure our planet’s magnetic field ( SN: 9/4/15 ). And at the heart of that melt, you’ll find a revolving, solid metal ball about 70 percent as wide as the moon.
This is the inner core ( SN: 1/28/19 ). Studies have suggested that this solid heart may rotate within the liquid outer core, compelled by the outer core’s magnetic torque. Researchers have also argued the mantle’s immense gravitational pull may apply an erratic brake on the inner core’s rotation, causing it to oscillate.
Evidence for the inner core’s fluctuating rotation first emerged in 1996 . Geophysicist Paul Richards of Columbia University’s Lamont-Doherty Earth Observatory in Palisades, N.Y., and Song, then also at Lamont-Doherty, reported that over a span of three decades, seismic waves from earthquakes took different amounts of time to traverse Earth’s solid heart.
The researchers inferred that the inner core rotates at a different speed than the mantle and crust, causing the time differences. The planet spins roughly 360 degrees in a day. Based on their calculations, the researchers estimated that the inner core, on average, rotates about 1 degree per year faster than the rest of Earth.
But other researchers have questioned that conclusion, some suggesting that the core spins slower than Song and Richards’ estimate or doesn’t spin differently at all.
In the new study, while analyzing global seismic data stretching back to the 1990s, Song and geophysicist Yi Yang — also at Peking University — made a surprising observation.
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Before 2009, seismic waves generated by sequences and pairs of repeating earthquakes — known as multiplets and doublets — traveled at different rates through the inner core. This indicated the waves from recurring quakes were crossing different parts of the inner core, and that the inner core was rotating at a different pace than the rest of Earth, aligning with Song’s previous research.
But around 2009, the differences in travel times vanished. That suggested the inner core had ceased rotating with respect to the mantle and crust, Yang says. After 2009, these differences returned, but the researchers inferred that the waves were crossing parts of the inner core that suggested it was now rotating in the opposite direction relative to the rest of Earth.
The researchers then pored over records of Alaskan earthquake doublets dating to 1964. While the inner core appeared to rotate steadily for most of that time, it seems to have made another reversal in rotation in the early 1970s, the researchers say.
Song and Yang infer that the inner core may oscillate with a roughly 70-year periodicity — switching directions every 35 years or so. Because the inner core is gravitationally linked to the mantle and magnetically linked to the outer core, the researchers say these oscillations could explain known 60- to 70-year variations in the length of Earth’s days and the behavior of the planet’s magnetic field. However, more work is needed to pin down what mechanisms might be responsible.
But not all researchers are on board. Yang and Song “identif[y] this recent 10-year period [that] has less activity than before, and I think that’s probably reliable,” says geophysicist John Vidale of the University of Southern California in Los Angeles, who was not involved in the research. But beyond that, Vidale says, things get contentious.
In 2022, he and a colleague reported that seismic waves from nuclear tests show the inner core may reverse its rotation every three years or so. Meanwhile, other researchers have proposed that the inner core isn’t moving at all. Instead, they say, changes to the shape of the inner core’s surface could explain the differences in wave travel times.
Future observations will probably help disentangle the discrepancies between these studies, Vidale says. For now, he’s unruffled by the purported chthonic standstill. “In all likelihood, it’s irrelevant to life on the surface, but we don’t actually know what’s happening,” he says. “It’s incumbent on us to figure it out.”
Nikk Ogasa is a staff writer who focuses on the physical sciences for Science News . He has a master’s degree in geology from McGill University, and a master’s degree in science communication from the University of California, Santa Cruz.
Our mission is to provide accurate, engaging news of science to the public. That mission has never been more important than it is today.
As a nonprofit news organization, we cannot do it without you.
Your support enables us to keep our content free and accessible to the next generation of scientists and engineers. Invest in quality science journalism by donating today.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
The adult sea spider ( Pycnogonum litorale ) in this microscope image made a full recovery after its back half was amputated, showing that arthropods can regrow more body parts than scientists realized.
No backside, no problem for some young sea spiders.
The creatures can regenerate nearly complete parts of their bottom halves — including muscles, reproductive organs and the anus — or make do without them, researchers report January 23 in Proceedings of the National Academy of Sciences .
The ability to regrow body parts isn’t super common, but some species manage to pull it off. Some sea slug heads can craft an entirely new body ( SN: 3/8/21 ). Sea spiders and some other arthropods — a group of invertebrates with an exoskeleton — can regrow parts of their legs. But researchers thought new legs were the extent of any arthropod’s powers, perhaps because tough exteriors somehow stop them from regenerating other body parts.
A mishap first clued evolutionary biologist Georg Brenneis in that sea spiders ( Pycnogonum litorale) might be able handle more complex repairs too. He accidentally injured one young specimen that he was working on in the lab with forceps. “It wasn’t dead, it was moving, so I just kept it,” says Brenneis, of the University of Vienna. Several months later, the sea spider had an extra leg instead of a scar, he and evolutionary biologist Gerhard Scholtz of Humbolt University of Berlin reported in 2016 in The Science of Nature .
In the new study, most of the 19 young spiders recovered and regrew missing muscles and other parts of their lower halves after amputation, though the regeneration wasn’t always perfect. Some juveniles sported six or seven legs instead of eight.
None of four adults regenerated. That may be because adults no longer shed their skin as they grow, suggesting that regeneration and molting are somehow linked, Brenneis says. Two young sea spiders also didn’t regenerate at all. The animals survived with only four legs and without an anus. Instead of pooping, the pair regurgitated waste out of their mouths.
Next up is figuring out whether other arthropods also regenerate more than scientists thought, and how sea spiders do it, Brenneis says. “I would like to see how it works.”
Erin I. Garcia de Jesus is a staff writer at Science News . She holds a Ph.D. in microbiology from the University of Washington and a master’s in science communication from the University of California, Santa Cruz.
Our mission is to provide accurate, engaging news of science to the public. That mission has never been more important than it is today.
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Your support enables us to keep our content free and accessible to the next generation of scientists and engineers. Invest in quality science journalism by donating today.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).
Cratonavis , a newly discovered bird from 120 million years ago, might have filled a similar niche as today’s raptors, though whether it could catch prey as large as illustrated here is up for debate.
A 120-million-year-old fossil bird found in China could offer some new clues about how landbound dinosaurs evolved into today’s flying birds. The dove-sized Cratonavis zhui sported a dinosaur-like head atop a body similar to those of today’s birds , researchers report in the January Nature Ecology & Evolution .
The flattened specimen came from the Jiufotang Formation, an ancient body of rock in northeastern China that is a hotbed for preserved feathered dinosaurs and archaic birds. CT scans revealed that Cratonavis had a skull that was nearly identical (albeit smaller) as those of theropod dinosaurs like Tyrannosaurus rex, paleontologist Li Zhiheng of the Chinese Academy of Sciences in Beijing and colleagues report. This means that Cratonavis still hadn’t evolved the mobile upper jaw found in modern birds ( SN: 5/2/18 ).
It’s among just a handful of specimens that belong to a recently identified group of intermediate birds known as the jinguofortisids, says Luis Chiappe, a paleontologist at the Natural History Museum of Los Angeles County who was not involved in the study. Its dino-bird mishmash “is not unexpected.” Most birds discovered from the Age of Dinosaurs exhibited more primitive, toothed heads than today’s birds, he says. But the new find “builds on our understanding of this primitive group of birds that are at the base of the tree of birds.”
Cratonavis also had an unusually elongated scapula and hallux, or backward-facing toe. Rarely seen in Cretaceous birds, enlarged shoulder blades might have compensated for the bird’s otherwise underwhelming flight mechanics, the researchers say. And that hefty big toe? It bucks the trend of shrinking metatarsals seen as birds continued to evolve. Cratonavis might have used this impressive digit to hunt like today’s birds of prey, Li’s team says.
Filling those shoes may have been too big of a job for Cratonavis , though. Given its size, Chiappe says, the dino-headed bird would have most likely been a petite hunter, taking down the likes of beetles, grasshoppers and the occasional lizard rather than terrorizing the skies.
Aaron Tremper is the editorial assistant for Science News Explores . He has a B.A. in English (with minors in creative writing and film production) from SUNY New Paltz and an M.A. in Journalism from the Craig Newmark Graduate School of Journalism’s Science and Health Reporting program. A former intern at Audubon magazine and Atlanta’s NPR station, WABE 90.1 FM, he has reported a wide range of science stories for radio, print, and digital media. His favorite reporting adventure? Tagging along with researchers studying bottlenose dolphins off of New York City and Long Island, NY.
Our mission is to provide accurate, engaging news of science to the public. That mission has never been more important than it is today.
As a nonprofit news organization, we cannot do it without you.
Your support enables us to keep our content free and accessible to the next generation of scientists and engineers. Invest in quality science journalism by donating today.
Science News was founded in 1921 as an independent, nonprofit source of accurate information on the latest news of science, medicine and technology. Today, our mission remains the same: to empower people to evaluate the news and the world around them. It is published by the Society for Science, a nonprofit 501(c)(3) membership organization dedicated to public engagement in scientific research and education (EIN 53-0196483).