This dinosaur might have used its feet to snag prey in midair like modern hawks

Modern birds evolved from dinosaurs, but it’s not clear how well birds’ ancient dino ancestors could fly (SN: 10/28/16). Now, a look at the fossilized feet of one nonavian dinosaur suggests that it may have hunted on the wing, like some hawks today.

The crow-sized Microraptor had toe pads very similar to those of modern raptors that can hunt in the air, researchers report December 20 in Nature Communications. That means the feathered, four-winged dinosaur probably used its feet to catch flying prey too, paleobiologist Michael Pittman of the Chinese University of Hong Kong and colleagues say (SN: 7/16/20).
Other researchers caution that toe pads alone aren’t enough to declare Microraptor an aerial hunter. But if the claim holds up, such a hunting style would reinforce a debated hypothesis that powered flight evolved multiple times among dinosaurs, a feat once attributed solely to birds.

Toe pads are bundles of scale-covered flesh on the undersides of dinosaur feet, similar to “toe beans” on dogs and cats. Because the pads are points where the living animal interacted with surfaces, toe pads give paleontologists a “sense of where the rubber meets the road,” says Alexander Dececchi, a paleontologist at Mount Marty University in Yankton, S.D., who was not involved in the new study.

These contact points can paint a clearer picture of an animal’s behavior by providing “details that the skeleton itself wouldn’t show,” says Thomas Holtz Jr., a dinosaur paleobiologist at the University of Maryland in College Park, who was also not involved in the study.

To investigate dinosaur toe pads, Pittman and colleagues turned to the Shandong Tianyu Museum of Nature in Linyi, China. It “has arguably the largest collection of feathered dinosaurs in the world, and, importantly, they haven’t been prepared extensively,” Pittman says. Many of these dinosaur skeletons are still surrounded by rock, which is where soft tissues can be preserved. Such a specimen “gives us the best chance of finding this wonderful soft tissue information,” he says.
Using special lasers that cause the otherwise nearly invisible soft tissue in the fossils to fluoresce, the team found 12 specimens with exceptionally well-preserved toe pads among the thousands examined (SN: 3/20/17).

The team compared the fossil toe pads with those of 36 types of modern birds, whose toe pads vary with their lifestyle. Predatory birds, for example, have protruding toe pads with spiky scales for grasping prey, while ground birds that spend their time walking and running have flatter toe pads. The analysis showed that Microraptor’s toe pads and other aspects of the feet, like the shape of the toe joints and claws, are most like those of modern hawks. That similarity suggests that the dinosaur could hunt prey midair and on the ground like hawks do, the team says.

Other dinosaurs, like the feathered Anchiornis, had flatter toe pads and straighter claws, suggesting a terrestrial lifestyle. That’s in line with ideas about this dinosaur being a poor flier, Pittman says.
The idea that Microraptor hunted like a hawk is consistent with other fossil evidence. One Microraptor fossil has been found with a bird in its stomach, and Microraptor‘s skeletal and soft tissue anatomy suggest some powered flight capability.

There’s still more work to do to figure out how well the dinosaur may have flown. “Microraptor is not a bird, but a close relative. Just because it has feet like a predatory bird doesn’t necessarily mean it must be catching prey in the exact same way,” Pittman says. But Microraptor’s hawklike lifestyle “is a strong possibility,” he adds.
Flight could have been useful to Microraptor when hunting, even if it couldn’t stack up to today’s fliers. Dececchi speculates that Microraptor’s anatomy probably prevented it from outflying birds, but may have helped it surprise otherwise out-of-reach prey, including flying and gliding animals.

“You only have to be fast or aerobatic enough to catch other things in your environment,” Holtz says. “So, it’s not improbable that [Microraptor was] catching things in the air on occasion.”

Other paleontologists are more skeptical that Microraptor hunted on the wing. “It would be a bit of a stretch to me to suggest that Microraptor was pursuing prey in an aerial context,” says Albert Chen, a paleobiologist at the University of Cambridge. The new findings inform only “what the foot was used for.”

Alternative hypotheses, such as a completely or partially terrestrial hunting style, could fit the data too, Holtz says, but the “feet are definitely playing a major role in their prey capture,” whether on the ground or in the air.

For now, the picture of Microraptor’s ecology remains fuzzy, but as lasers continue to increase the picture’s resolution, our understanding of dinosaur flight may reach new heights.

Just 3 ingredients can quickly destroy widely used PFAS ‘forever chemicals’

The undoing of toxic “forever chemicals” may be found in products in your pantry.

Perfluoroalkyl and polyfluoroalkyl substances, also known as PFAS, can persist in the environment for centuries. While the health impacts of only a fraction of the thousands of different types of PFAS have been studied, research has linked exposure to high levels of some of these widespread, humanmade chemicals to health issues such as cancer and reproductive problems.

Now, a study shows that the combination of ultraviolet light and a couple of common chemicals can break down nearly all the PFAS in a concentrated solution in just hours. The process involves blasting UV radiation at a solution containing PFAS and iodide, which is often added to table salt, and sulfite, a common food preservative, researchers report in the March 15 Environmental Science & Technology.
“They show that when [iodide and sulfite] are combined, the system becomes a lot more efficient,” says Garrett McKay, an environmental chemist at Texas A&M University in College Station who was not involved in the study. “It’s a big step forward.”

A PFAS molecule contains a chain of carbon atoms that are bonded to fluorine atoms. The carbon-fluorine bond is one the strongest known chemical bonds. This sticky bond makes PFAS useful for many applications, such as water- and oil-repellant coatings, firefighting foams and cosmetics (SN: 6/4/19; SN: 6/15/21). Owing to their widespread use and longevity, PFAS have been detected in soils, food and even drinking water. The U.S. Environmental Protection Agency sets healthy advisory levels for PFOA and PFOS — two common types of PFAS — at 70 parts per trillion.

Treatment facilities can filter PFAS out of water using technologies such as activated carbon filters or ion exchange resins. But these removal processes concentrate PFAS into a waste that requires a lot of energy and resources to destroy, says study coauthor Jinyong Liu, an environmental chemist at the University of California, Riverside. “If we don’t [destroy this waste], there will be secondary contamination concerns.”

One of the most well-studied ways to degrade PFAS involves mixing them into a solution with sulfite and then blasting the mixture with UV rays. The radiation rips electrons from the sulfite, which then move around, snipping the stubborn carbon-fluorine bonds and thereby breaking down the molecules.

But some PFAS, such as a type known as PFBS, have proven difficult to degrade this way. Liu and his colleagues irradiated a solution containing PFBS and sulfite for an entire day, only to find that less than half of the pollutant in the solution had broken down. Achieving higher levels of degradation required more time and additional sulfite to be poured in at spaced intervals.

The researchers knew that iodide exposed to UV radiation produces more bond-cutting electrons than sulfite. And previous research has demonstrated that UV irradiation paired with iodide alone could be used to degrade PFAS chemicals.

So Liu and his colleagues blasted UV rays at a solution containing PFBS, iodide and sulfite. To the researchers’ surprise, after 24 hours of irradiation, less than 1 percent of the stubborn PFBS remained.

What’s more, the researchers showed that the process destroyed other types of PFAS with similar efficiency and was also effective when PFAS concentrations were 10 times that which UV light and sulfite alone could degrade. And by adding iodide the researchers found that they could speed up the reaction, Liu says, making the process that much more energy efficient.

In the solution, iodide and sulfite worked together to sustain the destruction of PFAS molecules, Liu explains. When UV rays release an electron from iodide, that iodide is converted into a reactive molecule which may then recapture freed electrons. But here sulfite can step in and bond with these reactive molecules and with electron-scavenging oxygen in the solution. This sulfite “trap” helps keep the released electrons free to cut apart PFAS molecules for eight times longer than if sulfite wasn’t there, the researchers report.

It’s surprising that no one had demonstrated the effectiveness of using sulfite with iodide to degrade PFAS before, McKay says.

Liu and his colleagues are now collaborating with an engineering company, using their new process to treat PFAS in a concentrated waste stream. The pilot test will conclude in about two years.

Growing wildfire threats loom over the birthplace of the atomic bomb

There are things I will always remember from my time in New Mexico. The way the bark of towering ponderosa pines smells of vanilla when you lean in close. Sweeping vistas, from forested mountaintops to the Rio Grande Valley, that embellish even the most mundane shopping trip. The trepidation that comes with the tendrils of smoke rising over nearby canyons and ridges during the dry, wildfire-prone summer months.

There were no major wildfires near Los Alamos National Laboratory during the year and a half that I worked in public communications there and lived just across Los Alamos Canyon from the lab. I’m in Maryland now, and social media this year has brought me images and video clips of the wildfires that have been devastating parts of New Mexico, including the Cerro Pelado fire in the Jemez Mountains just west of the lab.
Wherever they pop up, wildfires can ravage the land, destroy property and displace residents by the tens of thousands. The Cerro Pelado fire is small compared with others raging east of Santa Fe — it grew only to the size of Washington, D.C. The fire, which started mysteriously on April 22, is now mostly contained. But at one point it came within 5.6 kilometers of the lab, seriously threatening the place that’s responsible for creating and maintaining key portions of fusion bombs in our nation’s nuclear arsenal.

That close call may be just a hint of growing fire risks to come for the weapons lab as the Southwest suffers in the grip of an epic drought made worse by human-caused climate change (SN: 4/16/20). May and June typically mark the start of the state’s wildfire season. This year, fires erupted in April and were amplified by a string of warm, dry and windy days. The Hermits Peak and Calf Canyon fires east of Santa Fe have merged to become the largest wildfire in New Mexico’s recorded history.

Los Alamos National Lab is in northern New Mexico, about 56 kilometers northwest of Santa Fe. The lab’s primary efforts revolve around nuclear weapons, accounting for 71 percent of its $3.9 billion budget, according the lab’s fiscal year 2021 numbers. The budget covers a ramp-up in production of hollow plutonium spheres, known as “pits” because they are the cores of nuclear bombs, to 30 per year beginning in 2026. That’s triple the lab’s current capability of 10 pits per year. The site is also home to radioactive waste and debris that has been a consequence of weapons production since the first atomic bomb was built in Los Alamos in the early 1940s (SN: 8/6/20).

What is the danger due to fire approaching the lab’s nuclear material and waste? According to literature that Peter Hyde, a spokesperson for the lab, sent to me to ease my concern, not much.

Over the last 3½ years, the lab has removed 3,500 tons of trees and other potential wildfire fuel from the sprawling, 93-square-kilometer complex. Lab facilities, a lab pamphlet says, “are designed and operated to protect the materials that are inside, and radiological and other potentially hazardous materials are stored in containers that are engineered and tested to withstand extreme environments, including heat from fire.”

What’s more, most of roughly 20,000 drums full of nuclear waste that were stored under tents on the lab’s grounds have been removed. They were a cause for anxiety during the last major fire to threaten the lab in 2011. According to the most recent numbers on the project’s website, all but 3,812 of those drums have been shipped off to be stored 655 meters underground at the Waste Isolation Pilot Plant near Carlsbad, N.M.

But there’s still 3,500 cubic meters of nuclear waste in the storage area, according to a March 2022 DOE strategic planning document for Los Alamos. That’s enough to fill 17,000 55-gallon drums. So potentially disastrous quantities of relatively exposed nuclear waste remain at the lab — a single drum from the lab site that exploded after transport to Carlsbad in 2014 resulted in a two-year shutdown of the storage facility. With a total budgeted cleanup cost of $2 billion, the incident is one of the most expensive nuclear accidents in the nation’s history.

Since the 2011 fire, a wider buffer space around the tents has been cleared of vegetation. In conjunction with fire suppression systems, it’s unlikely that wildfire will be a danger to the waste-filled drums, according to a 2016 risk analysis of extreme wildfire scenarios conducted by the lab.

But a February 2021 audit by the U.S. Department of Energy’s Office of Inspector General is less rosy. It found that, despite the removal of most of the waste drums and the multiyear wildfire mitigation efforts that the lab describes, the lab’s wildfire protection is still lacking.

According to the 20-page federal audit, the lab at that time had not developed a “comprehensive, risk-based approach to wildland fire management” in accordance with federal policies related to wildland fire management. The report also noted compounding issues, including the absence of federal oversight of the lab’s wildfire management activities.
Among the ongoing risks, not all fire roads were maintained well enough to provide a safe route for firefighters and others, “which could create dangerous conditions for emergency responders and delay response times,” the auditors wrote.

And a canyon that runs between the lab and the adjacent town of Los Alamos was identified in the report as being packed with 10 times the number of trees that would be ideal, from a wildfire safety perspective. To make matters worse, there’s a hazardous waste site at the bottom of the canyon that could, the auditors wrote, “produce a health risk to the environment and to human health during a fire.”

“The report was pretty stark,” says Edwin Lyman, director of nuclear power safety at the Union of Concerned Scientists. “And certainly, after all the warnings, if they’re still not doing all they need to do to fully mitigate the risk, then that’s just foolishness.”

A 2007 federal audit of Los Alamos, as well as nuclear weapons facilities in Washington state and Idaho, showed similar problems. In short, it seems little has changed at Los Alamos in the 14-year span between 2007 and 2021. Lab spokespeople did not respond to my questions about the lab’s efforts to address the specific problems identified in the 2021 report, despite repeated requests.

The Los Alamos area has experienced three major wildfires since the lab was founded — the Cerro Grande fire in 2000, Las Conchas in 2011 and Cerro Pelado this year. But we probably can’t count on 11-year gaps between future wildfires near Los Alamos, according to Alice Hill, the senior fellow for energy and the environment with the Council on Foreign Relations, who’s based in Washington, D.C.

The changing climate is expected to dramatically affect wildfire risks in years to come, turning Los Alamos and surrounding areas into a tinderbox. A study in 2018 in Climatic Change found that the region extending from the higher elevations in New Mexico, where Los Alamos is located, into Colorado and Arizona will experience the greatest increase in wildfire probabilities in the Southwest. A new risk projection tool that was recommended by Hill, called Risk Factor, also shows increasing fire risk in the Los Alamos area over the next 30 years.

“We are at the point where we are imagining, as we have to, things that we’ve never experienced,” Hill says. “That is fundamentally different than how we have approached these problems throughout human history, which is to look to the past to figure out how to be safer in the future…. The nature of wildfire has changed as more heat is added [to the planet], as temperatures rise.”

Increased plutonium pit production will add to the waste that needs to be shipped to Carlsbad. “Certainly, the radiological assessments in sort of the worst case of wildfire could lead to a pretty significant release of radioactivity, not only affecting the workers onsite but also the offsite public. It’s troubling,” says Lyman, who suggests that nuclear labs like Los Alamos should not be located in such fire-prone areas.
For now, some risks from the Cerra Pelado wildfire will persist, according to Jeff Surber, operations section chief for the U.S. Department of Agriculture Forestry Service’s efforts to fight the fire. Large wildfires like Cerra Pelado “hold heat for so long and they continue to smolder in the interior where it burns intermittently,” he said in a May 9 briefing to Los Alamos County residents, and to concerned people like me watching online.

It will be vital to monitor the footprint of the fire until rain or snow finally snuffs it out late in the year. Even then, some danger will linger in the form of “zombie fires” that can flame up long after wildfires appear to have been extinguished (SN: 5/19/21). “We’ve had fires come back in the springtime because there was a root underground that somehow stayed lit all winter long,” said Surber.

So the Cerro Pelado fire, and its occasional smoky tendrils, will probably be a part of life in northern New Mexico for months still. And the future seems just as fiery, if not worse. That’s something all residents, including the lab, need to be preparing for.

Meantime, if you make it out to the mountains of New Mexico soon enough, be sure to sniff a vanilla-flavored ponderosa while you still can. I know I will.

How scientists found an African bat lost to science for 40 years

Julius Nziza still remembers the moment vividly. Just before dawn on a chilly January morning in 2019, he and his team gently extracted a tiny brown bat from a net purposely strung to catch the nocturnal fliers. A moment later, the researchers’ whoops and hollers pierced the heavy mist blanketing Rwanda’s Nyungwe National Park. The team had just laid eyes on a Hill’s horseshoe bat (Rhinolophus hilli), which scientists hadn’t seen for nearly four decades.

Nziza, a wildlife veterinarian at Gorilla Doctors in Musanze, Rwanda, and a self-described “bat champion,” had been looking for the critically endangered R. hilli since 2013. For several years, Nziza and Paul Webala from Maasai Mara University in Narok, Kenya, with the help of Nyungwe park rangers, surveyed the forest for spots where the bats might frequent. They didn’t find R. hilli, but it helped them narrow where to keep looking.

In 2019, the team decided to concentrate on roughly four square kilometers in a high-elevation region of the forest where R. hilli had last been spotted in 1981. Accompanied by an international team of researchers, Nziza and Webala set out for a 10-day expedition in search of the elusive bat. It wasn’t rainy season yet, but the weather was already starting to turn. “It was very, very, very cold,” Nziza recalls.
Every night, from sunset until close to midnight, the researchers stretched nets across trails, where bats are most likely to fly, and kept watch. Then, after a few hours of rest, they woke early to check the traps again. It was cold enough that the bats could die if stuck too long.

At 4 a.m. on the fourth day, the researchers caught a bat with the distinctive horseshoe-shaped nose of all horseshoe bat species. But it looked slightly different from others they had captured. This one had darker fur and a pointed tip on its nose.

Everyone began shouting: “This is it!”
The researchers felt “almost 99 percent sure” they had found the lost bat. “We had a couple beers in the evening,” Nziza says. “It was worth celebration.” To be 100 percent sure, though, the team needed to compare its specimen to past ones of R. hilli. Fortunately, there were two in museums in Europe.

That’s because this isn’t the first time that R. hilli was lost, then found, to science. Victor van Cakenberghe, a retired taxonomist at the University of Antwerp in Belgium, rediscovered R. hilli 17 years after it was first seen in 1964. He says he still remembers finding the bat tangled in a mist net strung across a river. He kept the specimen and brought it back to a Belgian museum.

Nearly 40 years later, Nziza and colleagues compared the measurements of their bat, which was released into the wild, to the preserved bat. At long last, it can be confidently said that R. hilli was rediscovered again, researchers report March 11 in a preprint submitted to Biodiversity Data Journal.

And, for the first time ever, the scientists recorded R. hilli’s echolocation call. Now, the rangers can use acoustic detectors to keep an eye — or rather, an ear — on the bat (SN: 10/23/20). In nine months, they’ve already captured R. hilli calls from eight different locations in the same small area.
The team published its data to the open-access Global Biodiversity Information Facility in hopes of speeding up conservation efforts for the bat. Africa is home to over 20 percent of the world’s bats, but with a longstanding research focus on bats in Europe and the Americas, little is known about African bat species.

“It’s a whole new thing,” Nziza says. “That’s why everybody’s excited.”