Friday, February 23, 2024

 

Stunning 240 million-year-old 'Chinese dragon' fossil unveiled by scientists


News
By Ben Turner
 published 

A bizarre dragon-like creature that lived during the Triassic period used its remarkably long neck to hunt unsuspecting prey in shallow water, scientists have found.

A photo of the Dinocephalosaurus orientalis fossil.
A cropped photo of the Dinocephalosaurus orientalis fossil. (Image credit: National Museums Scotland)

Scientists have unveiled stunning fossils of an ancient seaborne "dragon" discovered in China.

The 240 million-year-old animal — nicknamed the "Chinese dragon" — belongs to the species Dinocephalosaurus orientalis, a reptile that used its remarkably long neck to ambush unsuspecting prey in shallow waters during the Triassic period (252 million to 201 million years ago).

The species was first found in limestone deposits in southern China in 2003, but scientists have now pieced together remains to reconstruct the full 16.8-foot (5 meters) span of the spectacular ancient carnivore for the first time.

The researchers revealed the new findings in a study published Feb. 23 in the journal Earth and Environmental Science: Transactions of the Royal Society of Edinburgh.

"It is yet one more example of the weird and wonderful world of the Triassic that continues to baffle paleontologists," Nick Fraser, keeper of natural sciences at National Museums Scotland said in a statement. "We are certain that it will capture imaginations across the globe due to its striking appearance, reminiscent of the long and snake-like, mythical Chinese Dragon." 

A full photo of dinocephalosaurus orientalis.

A full-size photo of dinocephalosaurus orientalis. (Image credit: National Museums Scotland)

The fossil reveals some of the ancient sea dragon's striking features.

First and foremost is its neck, which stretches nearly 7.7 feet (2.3 meters) and contains 32 separate vertebrae — in comparison, giraffes (as well as humans) have only seven neck vertebrae.

The snake-like shape of the dragon's articulable neck likely gave it a remarkable ability to sneak up on its prey, which it did after maneuvering into position with its flippered limbs. Some of the fish snared in the dragon's serrated teeth are still preserved inside the sea monster's belly.

The researchers note that though the strange creature may be reminiscent of the Loch Ness Monster, it is not closely related to the long-necked plesiosaurs that inspired the famous mythical creature.

"We hope that our future research will help us understand more about the evolution of this group of animals, and particularly how the elongate neck functioned," first-author Stephan Spiekman, a postdoctoral researcher based at the Stuttgart State Museum of Natural History, said in the statement.

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Cold, dry snaps accompanied three plagues that struck the Roman Empire


The finding reinforces an idea that climate can influence the spread of infectious diseases



A painting titled “The Plague of Rome” depicts the angel of death directing fatalities during the Antonine Plague. Climate shifts may have contributed to mortality during this and two other disease outbreaks that hit the Roman Empire, researchers say. 

JULES-ÉLIE DELAUNAY, MINNEAPOLIS INSTITUTE OF ART: GIFT OF MR. AND MRS. ATHERTON BEAN

A painting titled “The Plague of Rome” depicts the angel of death directing fatalities during the Antonine Plague. The angel of death has white wings and red fabric floating around it and yields a sword in one hand. Humans suffer and decay in the alley where the painting takes place.

By Brue Bower

JANUARY 26, 2024 AT 2:00 PM

For those who enjoy pondering the Roman Empire’s rise and fall — you know who you are — consider the close link between ancient climate change and infectious disease outbreaks. 

Periods of increasingly cooler temperatures and rainfall declines coincided with three pandemics that struck the Roman Empire, historian Kyle Harper and colleagues report January 26 in Science Advances. Reasons for strong associations between cold, dry phases and those disease outbreaks are poorly understood. But the findings, based on climate reconstructions from around 200 B.C. to A.D. 600, help “us see that climate stress probably contributed to the spread and severity of [disease] mortality,” says Harper, of the University of Oklahoma in Norman. 


Harper has previously argued that the First Plague Pandemic (also known as the Justinianic Plague), combined with declining global temperatures to weaken the Roman Empire (SN: 5/18/20). 

The new findings reinforce an idea that climate shifts can influence the origin and spread of infectious diseases, says Princeton University historian John Haldon. But it’s unclear whether a range of factors in the ancient Roman realm, including long-distance trade networks and densely populated settlements, heightened people’s vulnerability to disease outbreaks, says Haldon, who did not participate in the new study. 

To reconstruct the ancient climate, marine palynologist Karin Zonneveld and colleagues turned to an extensive sample of fossilized dinoflagellates. These single-celled algae had been preserved in radiocarbon-dated slices from a sediment core previously extracted in southern Italy’s Gulf of Taranto.  

Dinoflagellates live in the sunlit upper part of the sea. Different species of this organism assume signature shapes in the late summer and autumn before settling on the ocean floor. Some species live only in cold waters, others only in warm waters. 

In late summer and autumn, water temperature in the Gulf of Taranto closely aligns with southern Italy’s air temperature, says Zonneveld, of the University of Bremen in Germany. Her group tracked changes in the composition of dinoflagellate species in sediment slices to estimate late summer/autumn temperatures in southern Italy during the Roman Empire.  

The team also used dinoflagellates to gauge changes in ancient rainfall. Plentiful rainfall in central and northern Italy causes rivers to discharge nutrient-rich water into the Gulf of Taranto. Dinoflagellate species known to rely on plentiful nutrients thrive under those conditions and end up on the sea floor. Other dinoflagellate species prefer nutrient-poor water. Their preservation in underwater sediment reflects stretches of scant rainfall. 

The dinoflagellate analysis revealed that warm, stable temperatures and regular rainfall occurred from around 200 B.C. to A.D. 100, Zonneveld says. That time corresponds to the Roman Warm Period, a time of political and social stability for the Roman Empire. 

Then, phases of increasingly cold and dry conditions occurred shortly before or during three pandemics: the Antonine Plague, which spread from Egypt to Europe and the British Isles in the late 160s; the Plague of Cyprian, which struck during a time of Roman political turmoil in the mid-200s; and the Justinianic Plague, which reached Italy by 543. By the late 500s, average temperatures were about 3 degrees Celsius colder than the highest averages during the Roman Warm Period. 

It’s unclear how high death rates climbed during these disease outbreaks and how they might factor into the fall of the empire. The Roman Empire’s power and influence fell dramatically by around the time of the Justinianic Plague, though the eastern half of the empire lasted until the fall of its capital in Constantinople in 1453. 

And despite providing valuable new climate information from ancient Roman times, neither Zonnefeld’s team nor anyone else can say with certainty how temperature and rainfall shifts may have aided the spread of infectious diseases, says classical archaeologist Brandon McDonald of the University of Basel in Switzerland. 

While it’s known that the Justinianic Plague was caused by the Black Death bacterium Yersinia pestis, specific disease-causing agents for the Antonine Plague and the Plague of Cyprian remain unknown, McDonald says, further muddying attempts to explain how climate may have influenced those events.  

Economic and social historian Colin Elliott notes that many infectious microbes flourish under cold, dry conditions.  

In Elliott’s new book that focuses on the Antonine Plague, Pox Romana, he argues that grain production in Italy and other parts of the Roman Empire suffered during cold years. As a result, hungry people in the Italian countryside may have migrated to cities where imported grain was available, says Elliott, of Indiana University in Bloomington. “Diseases moved with migrants, but surges of malnourished and immunologically [vulnerable] populations into cities almost certainly increased pandemic virulence as well.” 

Intriguingly, the new study also raises the possibility that cooler and drier autumns reduced malaria cases, says Ohio State University historian Kristina Sessa. The milder climate may have impaired or killed temperature-sensitive mosquitoes that regularly transmitted the dangerous disease in southern Italy. 

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The United States was on course to eliminate syphilis. Now it’s surging


The syphilis crisis is hitting pregnant people and newborns especially hard


three vintage public health posters that promote syphilis screening

These public health posters, made as part of the Federal Art Project, encouraged syphilis screening during the Great Depression. National data collection for syphilis began in 1941. The rate in the 1940’s was as high as 450 cases per 100,000 people.

ILLINOIS WPA ART PROJECT

By Aimee Cunningham

FEBRUARY 22, 2024 

Once on the path to eliminating syphilis, the United States has reversed course, with cases of the infectious disease surging.

From a low of under 32,000 cases in 2000, the number of people with syphilis has rocketed to more than 207,000 in 2022, the U.S. Centers for Disease Control and Prevention reported in January. That’s 62 cases per 100,000 people.

The crisis is hitting pregnant people and babies especially hard. The maternal rate for syphilis during pregnancy rose from 87 per 100,000 births in 2016 to 280 per 100,000 births in 2022, the CDC reported on February 13. Without treatment, pregnant people can pass a syphilis infection to the fetus. That can cause congenital syphilis and lead to miscarriage, stillbirth, premature birth, severe health problems after birth or the infant’s death. More than 3,700 babies were born with syphilis in 2022, roughly ten times the number in 2012.


More information: The stages, testing and treatment of syphilis

Testing is a crucial step in finding cases. Syphilis is “the great pretender,” says Allison Agwu, a pediatric and adult infectious disease clinician and researcher at Johns Hopkins School of Medicine. “It can look like a bunch of other things.” The disease moves through several stages, at times featuring symptoms common to other conditions and at other times having no symptoms.

People can get tested — usually with a blood test — by their primary care provider or at a public health clinic or an urgent care facility, for example. With syphilis rates so high, Agwu would like to see testing for syphilis destigmatized and become easier to discuss as part of a regular medical checkup. “If you have been sexually active ever, you should have a syphilis test,” she says.

Science News spoke with Agwu about the surge in cases and what needs to be done better to prevent syphilis. The interview was edited for length and clarity.

SN: What are some of the factors behind the rise in syphilis cases in the United States?

Agwu: It’s multifactorial. Syphilis is oftentimes asymptomatic, so people can have it for years and not know they have it — they missed the signs when it was symptomatic. We have a whole public health infrastructure imploding with decreased access and funding. The impact is magnified in communities that have the least access to begin with and that are relying on those clinics or places that funding is being pulled from. There is stigma. There have been medicine shortages.

The infrastructure [built] to control syphilis — almost eliminating the disease a few decades ago — has really collapsed. We’re at this perfect storm for increases in syphilis and, as a result, congenital syphilis as well.

SN: Where are there missed opportunities in testing for syphilis?

Agwu: I’ve been in the infectious disease field for a long time. We’ve had the 80-year woman who comes in and she’s confused or disoriented. That’s neurosyphilis [a complication of syphilis that impacts the brain and nervous system], from never being treated for a syphilis infection. We all should be thinking about syphilis, particularly with the rates that we’re seeing. Healthcare providers should just test people.

There’s testing in early pregnancy. If someone is diagnosed with syphilis, they should be treated in pregnancy. This is one of the times you absolutely need to treat them to avert transmission to the baby. I think part of the challenge with syphilis in pregnancy — actually, all sexually transmitted infections in pregnancy — is that oftentimes there are people that society thinks of as sexual beings and those that we do not. I’ve talked to pregnant women who say, well I got my testing, but there was not a conversation about how I can stay negative. So the counseling around staying negative, I think we may miss that.

We certainly have had scenarios where the baby comes, and the mom or the birthing parent has had no prenatal care. [In that case] we’re testing at delivery.

Rising maternal syphilis rates

The maternal syphilis rate, the number of live births to women with syphilis per 100,000 live births, increased for all groups from 2016 to 2022. The biggest jump — 783 percent — occurred among American Indian and Alaska Native women giving birth.

SN: What needs to happen to bring syphilis cases back down?

Agwu: It’s education, and not in a way to scare people, but just: This is what you can have and the different ways you can get it, and here’s how you can test for it, here’s where you can test for it.

We need to normalize sexuality and sexual exploration and not vilify it. We need to destigmatize the diagnosis so people are more likely to then tell their partners, so their partners can also get tested and treated. Instead of having someone prove that they need to have additional testing, how about we just test people — instead of creating a stigma around, well do you need to get tested again. Acknowledging that people are sexual beings, even when they’re pregnant.

COVID-19 really highlighted the problems we were having with our public health infrastructure. We need to think about how we can effectively provide sexual health care and give testing, prevention, treatment all in a way that is packaged in a positive light. Take it out of the dark.

The stages, testing and treatment of syphilis

Syphilis — caused by the bacteria Treponema pallidum — is described in terms of stages.

In the first stage, the only sign is one or several sores at the site a person was infected, such as on the penis, around the vagina, in the anus or mouth. The sores are usually painless and remain for three to six weeks. During the second stage, people can have a rash, headaches, fever, muscle aches or fatigue.

Once those symptoms pass, a person can be asymptomatic for years. But some people progress to a fourth, potentially fatal stage, which damages many organs, including the brain, nerves and heart.

The guideline for asymptomatic adolescents and adults is to test those who have been sexually active and are at increased risk, which includes people who have an HIV infection or other sexually transmitted infections and men who have sex with men. The recommendation for pregnant people is to test for syphilis as early as possible, ideally during their first prenatal visit.

Syphilis is treated with a shot of a special formulation of penicillin. There has been a shortage of the drug, which is the only effective treatment during pregnancy. Nonpregnant people can also take the oral antibiotic doxycycline for treatment.

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