Dinosaur ‘mummies’ may not be rare flukes after all

It might be easier for dinosaurs to “mummify” than scientists thought.

Unhealed bite marks on fossilized dinosaur skin suggest that the animal’s carcass was scavenged before being covered in sediment, researchers report October 12 in PLOS ONE. The finding challenges the traditional view that burial very soon after death is required for dinosaur “mummies” to naturally form.

The new research centers on Dakota, an Edmontosaurus fossil unearthed in North Dakota in 1999. About 67 million years ago, Dakota was a roughly 12-meter-long, duck-billed dinosaur that ate plants. Today, Dakota’s fossilized limbs and tail still contain large areas of well-preserved, fossilized scaly skin, a striking example of dinosaur “mummification.”

The creature isn’t a true mummy because its skin has turned into rock, rather than being preserved as actual skin. Researchers have come to refer to such fossils with exquisitely preserved skin and other soft tissues as mummies.

In 2018, paleontologist Clint Boyd of the North Dakota Geological Survey in Bismarck and colleagues began a new phase of cleaning up and examining the dinosaur fossil. The team had found what looked like tears in the tail skin and puncture holes on the animal’s right front foot. To investigate what may have caused the skin marks, the researchers teamed up with Stephanie Drumheller, a paleontologist at the University of Tennessee in Knoxville, to remove extra rocky material around the marks.

The holes in the skin — particularly those on the front limb — are a close match for bite wounds from prehistoric relatives of modern-day crocodiles, the researchers say. “This is the first time that’s been seen in dinosaurian soft tissues,” Drumheller says.

Because the marks on the tail are larger than those on the front limb, the team thinks that at least two carnivores munched on the Edmontosaurus carcass, probably as scavengers because the wounds didn’t heal. But scavenging doesn’t fit into the traditional view of mummification.

“This assumption of rapid burial has been baked into the explanation for mummies for a while,” Drumheller says. That clearly wasn’t the case for Dakota. If scavengers had enough time to snack on its body, then the deceased dino had been out in the open for a while.

Observing Dakota’s deflated skin envelope, shrink-wrapped to the underlying bone with no muscle or other organs, Drumheller had an unexpected “eureka moment,” she says. “I had seen something like this before. It just wasn’t in the paleontological literature. It was in the forensics literature.”

When some smaller modern scavengers like raccoons feed on the internal organs of a larger carcass, the scavengers rip open the carcass’s body. The forensics research showed that this hole gives any gasses and fluids from further decomposition an escape route, allowing the remaining skin to dry out. Burial could happen afterward.

The researchers “make a very good point,” says Raymond Rogers, a researcher at Macalester College in Saint Paul, Minn., who studies how organisms decay and fossilize and wasn’t involved in the research. “It would be very unlikely for a carcass to achieve advanced stages of desiccation and also experience rapid burial. These two generally presumed prerequisites for mummification seem to be somewhat incompatible.”

Fossilization of soft tissues — like skin or brains or fleshy head combs — is uncommon, but not unheard of (SN: 8/20/21; SN: 12/12/13). “If [soft tissue] requires some spectacular confluence of weird events to get it fossilized at all, it’s far more common than then you would expect if that was the case,” Drumheller says. Perhaps, then, mummies originating from common carcass fates could explain this.

But while dry, “jerkylike” skin could survive long enough to be buried, the conditions involved aren’t necessarily common, says Evan Thomas Saitta, a paleontologist at the University of Chicago who was not involved with the study.

“I still suspect that this actual process is a very precise sequence of events, where if you get the timing wrong, you end up without a mummy dinosaur,” he says.

Understanding that sequence of events, and just how common it is, requires figuring out how fossilization proceeds after a mummy’s burial. This is an area of research that Boyd says he’s interested in looking into next.

“Is it just the same fossilization process as for the bones?” he asks. “Or do we also need a different set of geochemical conditions to then fossilize the skin?”

Wind turbines could help capture carbon dioxide while providing power

Wind turbines could offer a double whammy in the fight against climate change.

Besides harnessing wind to generate clean energy, turbines may help to funnel carbon dioxide to systems that pull the greenhouse gas out of the air (SN: 8/10/21). Researchers say their simulations show that wind turbines can drag dirty air from above a city or a smokestack into the turbines’ wakes. That boosts the amount of CO2 that makes it to machines that can remove it from the atmosphere. The researchers plan to describe their simulations and a wind tunnel test of a scaled-down system at a meeting of the American Physical Society’s Division of Fluid Dynamics in Indianapolis on November 21.
Addressing climate change will require dramatic reductions in the amount of carbon dioxide that humans put into the air — but that alone won’t be enough (SN: 3/10/22). One part of the solution could be direct air capture systems that remove some CO2 from the atmosphere (SN: 9/9/22).

But the large amounts of CO2 produced by factories, power plants and cities are often concentrated at heights that put it out of reach of machinery on the ground that can remove it. “We’re looking into the fluid dynamics benefits of utilizing the wake of the wind turbine to redirect higher concentrations” down to carbon capture systems, says mechanical engineer Clarice Nelson of Purdue University in West Lafayette, Ind.

As large, power-generating wind turbines rotate, they cause turbulence that pulls air down into the wakes behind them, says mechanical engineer Luciano Castillo, also of Purdue. It’s an effect that can concentrate carbon dioxide enough to make capture feasible, particularly near large cities like Chicago.

“The beauty is that [around Chicago], you have one of the best wind resources in the region, so you can use the wind turbine to take some of the dirty air in the city and capture it,” Castillo says. Wind turbines don’t require the cooling that nuclear and fossil fuel plants need. “So not only are you producing clean energy,” he says, “you are not using water.”

Running the capture systems from energy produced by the wind turbines can also address the financial burden that often goes along with removing CO2 from the air. “Even with tax credits and potentially selling the CO2, there’s a huge gap between the value that you can get from capturing it and the actual cost” that comes with powering capture with energy that comes from other sources, Nelson says. “Our method would be a no-cost added benefit” to wind turbine farms.

There are probably lots of factors that will impact CO2 transport by real-world turbines, including the interactions the turbine wakes have with water, plants and the ground, says Nicholas Hamilton, a mechanical engineer at the National Renewable Energy Laboratory in Golden, Colo., who was not involved with the new studies. “I’m interested to see how this group scaled their experiment for wind tunnel investigation.”

Insect swarms might generate as much electric charge as storm clouds

You might feel a spark when you talk to your crush, but living things don’t require romance to make electricity. A study published October 24 in iScience suggests that the electricity naturally produced by swarming insects like honeybees and locusts is an unappreciated contributor to the overall electric charge of the atmosphere.

“Particles in the atmosphere easily charge up,” says Joseph Dwyer, a physicist at the University of New Hampshire in Durham who was not involved with the study. “Insects are little particles moving around the atmosphere.” Despite this, the potential that insect-induced static electricity plays a role in the atmosphere’s electric field, which influences how water droplets form, dust particles move and lightning strikes brew, hasn’t been considered before, he says.
Scientists have known about the minuscule electric charge carried by living things, such as insects, for a long time. However, the idea that an electric bug-aloo could alter the charge in the air on a large scale came to researchers through sheer chance.

“We were actually interested in understanding how atmospheric electricity influences biology,” says Ellard Hunting, a biologist at the University of Bristol in England. But when a swarm of honeybees passed over a sensor meant to pick up background atmospheric electricity at the team’s field station, the scientists began to suspect that the influence could flow the other way too.

Hunting and colleagues, including biologists and physicists, measured the change in the strength of electric charge when other honeybee swarms passed over the sensor, revealing an average voltage increase of 100 volts per meter. The denser the insect swarm, the greater the charge produced.

This inspired the team to think about even larger insect swarms, like the biblical hordes of locusts that plagued Egypt in antiquity (and, in 2021, Las Vegas (SN: 3/30/21)). Flying objects, from animals to airplanes, build up static electricity as they move through the air. The team measured the charges of individual desert locusts (Schistocerca gregaria) as they flew in a wind tunnel powered by a computer fan. Taking data on locust density from other studies, the team then used a computer simulation based on the honeybee swarm data to scale up these single locust measurements into electric charge estimates for an entire locust swarm. Clouds of locusts could produce electricity on a per-meter basis on par with that in storm clouds, the scientists report.

Hunting says the results highlight the need to explore the unknown lives of airborne animals, which can sometimes reach much greater heights than honeybees or locusts. Spiders, for example, can soar kilometers above Earth when “ballooning” on silk threads to reach new habitats (SN: 7/5/18). “There’s a lot of biology in the sky,” he says, from insects and birds to microorganisms. “Everything adds up.”

Though some insect swarms can be immense, Dwyer says that electrically charged flying animals are unlikely to ever reach the density required to produce lightning like storm clouds do. But their presence could interfere with our efforts to watch for looming strikes that could hurt people or damage property.

“If you have something messing up our electric field measurements, that could cause a false alarm,” he says, “or it could make you miss something that’s actually important.” While the full effect that insects and other animals have on atmospheric electricity remains to be deduced, Dwyer says these results are “an interesting first look” into the phenomenon.

Hunting says this initial step into an exciting new area of research shows that working with scientists from different fields can spark shocking findings. “Being really interdisciplinary,” he says, “allows for these kinds of serendipitous moments.”

Bizarre aye-aye primates take nose picking to the extreme

Aye-ayes are true champions of nose picking.

A new video offers the first evidence that these nocturnal lemurs of Madagascar stick their fingers up their noses and lick off the mucus. They don’t use just any finger for the job, either. The primates go spelunking for snot with the ultralong, witchy middle finger they typically use to find and fish grubs out of tree bark.

A reconstruction of the inside of an aye-aye’s head based on CT scans shows that this spindly digit probably pokes all the way through the animal’s nasal passages to reach its throat, researchers report online October 26 in the Journal of Zoology.
“This is a brilliant example of how science can serve human curiosity,” says Michael Haslam, a primate archaeologist based in London who was not involved in the new work. “My first take was that it’s a cool — and a bit creepy — video, but [the researchers] have gone beyond that initial reaction of ‘What on Earth?’ to actually explore what’s happening inside the animal.”

The new footage stars Kali, a female aye-aye (Daubentonia madagascariensis) at the Duke Lemur Center in Durham, N.C. “The aye-aye stopped eating and started to pick its nose, and I was really surprised,” says evolutionary biologist Anne-Claire Fabre, who filmed the video. “I was wondering where the finger was going.” An aye-aye is about as big as a house cat, but its clawed middle finger is some 8 centimeters long. And Kali was plunging almost the entire digit up her snout to sample her own snot with dainty licks.

“There is one moment where the camera is [shaking], and I was giggling,” says Fabre, of the Natural History Museum of Bern in Switzerland. Afterward, she asked her colleagues if they had ever seen an aye-aye picking its nose. “The ones that were working a lot with aye-ayes would tell me, ‘Oh, yeah, it’s happening really often,’” says Fabre, who later witnessed the behavior in several other aye-ayes.
This got Fabre and her colleagues curious about how many other primate species have been caught with their fingers in their nostrils. The researchers scoured the literature for past studies and the internet for other videos documenting the behavior.

Unfortunately, “most of the literature that we were finding were jokes,” Fabre says. “I was really surprised, because there is a lot of literature on other types of pretty gross behaviors, such as coprophagy,” or poo eating, among animals (SN: 7/19/21). But between all the bogus articles, the team did find some real reports of primate nose picking, including research done by Jane Goodall in the 1970s.

Aye-ayes are now the 12th known species of primate, including humans, to pick their noses and snack on the snot, the researchers found. Others include gorillas, chimpanzees, bonobos, orangutans and macaques. Nose pickers tend to be primates that have especially good dexterity and use tools.

“The team [has] given us the first map of nose picking across our primate family tree, which immediately raises questions about just how much of this behavior is happening out there, unseen or unreported,” Haslam says. He remembers once seeing a capuchin monkey using a twig or stem to pick its nose (SN: 9/6/15).

“I’m surprised that there aren’t more reports on nose picking, especially from zoos where animals are watched every day,” Haslam adds. “Perhaps our own social stigma around it means that scientists are less likely to want to report nose-picking animals, or it may even be seen as too common to be interesting.”
The fact that so many primate species have been spotted picking their noses and eating the boogers makes Fabre’s team and Haslam wonder whether this seemingly nasty habit has some unknown advantage. Perhaps eating germ-laden boogers boosts the immune system.

For now, untangling the evolutionary origins and potential perks of nose picking will require a more complete census of what species — primate or otherwise — mine and munch on their own mucus.