Large theropods thrived near South Pole, Australian tracks show

Melissa Lowery and Anthony Martin, co-authors of the new paper, examine a theropod track.

A discovery of dinosaur tracks on Australia’s southern coast — dating back to the Early Cretaceous when Australia was still connected to Antarctica — indicates that large theropod dinosaurs thrived in this polar environment, prowling the river floodplains when the ice thawed during the summers. 

The journal Alcheringa published the analyses of the tracks made in the Wonthaggi Formation south of Melbourne between 120 and 128 million years ago. The find includes 18 theropod tracks and four tracks made by ornithopods — small, herbivorous dinosaurs that may have been prey for the theropods. 

“These numerous tracks are the best evidence yet that these former polar environments supported large carnivores,” says Anthony Martin, first author of the study and a professor in Emory’s Department of Environmental Sciences. “The large theropods would likely have fed on prey such as smaller dinosaurs, fish and turtles.” 

Theropods, from the ancient Greek for “wild beast foot,” are a dinosaur clade characterized by walking on two legs and feet with three clawed toes. They belong to the same evolutionary group as Allosaurus, Tyrannosaurus rex and Velociraptor. 

The largest track from the current find was 18.5 inches long. “The hip height of that theropod would have been about the same as the full height of a tall, modern-day human — or a bit more than six feet tall,” Martin says.

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The promise and pitfalls of 'climatopias' for building resilience in coastal communities

"We need to invest in projects for low-income groups because they are the most impacted by climate change," says Jola Ajibade, associate professor in Emory's Department of Environmental Sciences. (Photo by Carol Clark)

By Carol Clark

Idowu (Jola) Ajibade grew up in Lagos, Nigeria, a low-lying city built around a lagoon bordered by the Atlantic Ocean. Flooding is a routine occurrence during the rainy season. 

“It was bad,” Ajibade recalls of living on the ground floor of a building during her early childhood. “We would get inundated with water until my family relocated to the upper level in a rental apartment. I don’t have many childhood photos or videos like most people. Our belongings got flooded out yearly — we replaced some items, but some things are just irreplaceable.” 

These experiences are part of what drove Ajibade, associate professor in Emory’s Department of Environmental Sciences, to become an environmental and human geographer. She explores how climate change is transforming the lives, livelihoods, social-cultural landscapes and housing access for low-income groups and historically marginalized communities. 

Nature recently published a commentary by Ajibade and Sameer Shah from the University of Washington considering whether futuristic settlements on water, so-called “climatopias,” are viable ways to build resilience in coastal communities. 

As urban populations boom, even as climate change exacerbates flood risks in coastal areas, governments are working with developers, architects and engineers to try to make their cities more resilient. Many leaders are promoting showcase climatopias as viable solutions. 

Ajibade and Shah, however, take a more cautious approach in their Nature commentary. “Ultimately, climatopias can become technical solutions to a complex global challenge only if stricter planning processes, impact assessments, ecosystem protection and justice for communities are at the heart of any coastal future,” the authors write. 

Examples of climatopias

The Maldives Floating City is a development of modular floating platforms taking shape in the Indian Ocean, set for completion in 2027. The development aims to help the Maldives, one of the world’s low-lying nations, survive the effects of rising sea levels. 

Maasbommel in the Netherlands offers an example of an amphibious climatopia. The 32 amphibious homes of Maasbommel are anchored to the ground but also fastened to flexible mooring posts that allow them to move upward by more than five meters and float during floods. 

Reclamation, or the practice of creating new land from oceans by filling the water with rock, cement and other materials, forms the basis for other climatopia projects worldwide. One famous example is Eko Atlantic, an enclave of sleek, modern skyscrapers rising on a two-square-mile platform of reclaimed land on the Lagos waterfront. 

Dredging for Eko Atlantic began in 2009, and construction is still underway. When completed, Eko Atlantic will comprise offices and luxury condos expected to house 250,000 residents, who will be protected from storm surges by an eight-mile-long, 20-foot-tall wall of concrete and granite. 

Developers laud Eko Atlantic as a way to attract transnational investment, drive economic growth, combat the effects of climate change and house more people in one of the world’s fastest-growing megacities. 

Getting multiple perspectives 

While working on her PhD as a graduate student at Western University in Canada in 2012, Ajibade returned to her hometown to research community vulnerability and resilience in Lagos, a city sharply divided between the rich and poor. 

“I talked to people who lived in slums and those in wealthy areas to get both their perspectives,” she says. “There was torrential rainfall during my visit and, at one point, I had to wade through chest-high water.” 

She notes that construction on the Eko Atlantic project has been blamed for displacing some communities and for diverting water in ways that increase the flooding burden on the poorest of the poor. Others counter that poor communities have caused the increase in flooding by building shanties on drainage systems and filling them with trash. 

Some believe that Eko Atlantic will benefit low-income people by providing service jobs. Others doubt that the economic boon of the pricy new real estate will “trickle down” in ways that benefit those who need it most. 

So is Eko Atlantic worth the billions of dollars that have already been invested in it during the past 16 years? 

“It depends on who you ask,” Ajibade says. 

Improving the drainage infrastructure throughout Lagos, including in the poorest areas, might be another solution that could benefit more people. 

“We need to invest in projects for low-income groups because they are the most impacted by climate change,” she notes. “Climatopias can’t be the focal solution, and they should be carefully considered so that they don’t damage fragile ecosystems, accelerate ocean colonialism or create even more problems for people who are already living on the margins of society.”

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How cows expanded a neuroscientist's mind

"Cows are emotional, intelligent and loyally affectionate," says Gregory Berns, Emory professor of psychology.

During the COVID-19 pandemic, Emory neuroscientist Gregory Berns moved with his wife to a farm about an hour south of Atlanta. His reinvention, from city dweller to farmer, led to Berns’ upcoming book, “Cowpuppy: An Unexpected Friendship and a Scientist’s Journey into the Secret World of Cows.” Set for publication by Harper Horizon on Aug. 20, the book describes Berns’ crash course in becoming a cattleman and his ongoing fascination with the interior world of cows. 

“I originally got cows for biological help, to keep the grass down,” Berns explains. “But then my relationship with them turned into something more. I started seeing the world through a cow’s eyes. There’s a common misconception that cows are dumb animals, but that’s just because most people haven’t had the opportunity to interact with them. I decided it was time to set the record straight on cow brains.”

His new lifestyle also inspired Berns to develop an undergraduate class to debut this fall: “Psychology of Sustainability.” 

Read the full story here.

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White House taps Emory expert to speak on climate resilience panel

“The climate is changing. We also need to think about ways to change ourselves as a society so we can begin to meet the important challenges ahead of us,” says Idowu (Jola) Ajibade, associate professor in Emory University’s Department of Environmental Sciences. 

As a deadly heat waves blanketed parts of the United States, Ajibade spoke on a guest panel of experts for a meeting of the U.S. President’s Council of Advisors on Science and Technology (PCAST). PCAST consists of experts from who advise the president on policy matters where the understanding of science, technology and innovation is key. 

The public meeting, entitled “Social Impact of Research: Climate Resilience,” was livestreamed on July 11 and also recorded. 

Ajibade is an environmental and human geographer. She explores how climate change is transforming the lives, livelihoods, social-cultural landscapes and housing access for members of historically marginalized communities. 

“If we’re going to build resilience to climate change, we need multiple perspectives, multiple expertise and, certainly multiple methods,” Ajibade explains during her PCAST presentation. 

Watch the full presentation in the video above.

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Rabies outbreaks in Costa Rica cattle linked to deforestation

Cows in a forest of the Alajuela province of Costa Rica meander near the entrance to a cave where researchers are gathering data on vampire bats and the ecology of the rabies virus. Photo by Amanda Vicente.

By Carol Clark

Deforestation in Costa Rica raises the risk of cattle becoming infected with rabies by vampire bats, finds a new study. Emerging Infectious Diseases published the research by disease ecologists at Emory University. 

“A healthy tropical forest has phenomenal diversity — not just among plants and mammals like monkeys and bats, but also among microorganisms,” says Thomas Gillespie, Emory professor and chair of the Department of Environmental Sciences and senior author of the study. “When you destroy parts of a forest, the diversity goes down and the dynamics of disease transmission may change in a way that leads to the emergence of new pathogens or the reemergence of existing ones.” 

The Costa Rica economy relies heavily on ecotourism. Approximately 25% of its territory is protected under its National System of Conservation Areas, the largest percentage of protected areas accounted for by any country in the world, according to the Global Alliance of National Parks. 

Agriculture, however, is also an important economic sector and often encroaches into unprotected tropical forest areas. Livestock farms cover about 38% of the country’s territory, according to the United Nations Environment Program. 

“The government has done an amazing job of protecting much of its tropical forest,” Gillespie says. “In some areas, however, the country has high rates of deforestation due to clearing of the land for agricultural uses. It’s a big dichotomy.” 

Rabies is a viral disease most often transmitted by the bite of a rabid mammal. Vaccination campaigns have been largely effective at preventing rabies outbreaks in dogs in Costa Rica. The virus, though, keeps reemerging in cattle, spread by vampire bats. 

A vampire bat is held in a researcher's gloved hands. The bat's razor-sharp teeth allow it to make an incision in an animal without the animal feeling it. Photo by Neto Villalobos.

Found in tropical and subtropical areas of Central and South America, vampire bats feed solely on blood. Unlike other bats, they can walk — and even run — on land. They feed at night, stealthily approaching a sleeping mammal. Razor-sharp teeth and surgical precision allow the bats to make an incision in an animal, such as in the hock of a cow, without the animal feeling it. An anticoagulant in vampire bat saliva keeps the blood flowing as the bat laps up a meal. 

The researchers wanted to better understand the factors associated with rabies outbreaks in cattle in Costa Rica. They drew from data of the National Animal Health Service of Costa Rica to map the time and locations of rabies outbreaks in cattle from 1985 to 2020 in both northern and southern regions of the country where tropical forest has been cleared for agriculture. 

They also mapped land-use data across the same time for the outbreak sites, including a radius of 10 kilometers for each site, the maximum foraging range for vampire bats. They then used geographic information system software to generate spatial probability estimations based on these known outbreaks. 

The results showed a link between the location of forest habitat and an outbreak. Each one-kilometer increase in distance from forest increased the probability of an outbreak by 4%. The researchers theorize that decreased availability of bat-roosting sites within forested habitat appears to increase the preference of vampire bats to feed on cattle, as opposed to wild mammals. 

“We found the highest probability of rabies outbreaks in Puntarenas Province in the south, indicating the need for localized, preventative interventions in that region to avoid rabies reemergence in people,” says Julie Clennon, an eco-epidemiologist in Emory’s Department of Environmental Sciences and co-author of the study. 

A forest in Alajuela province with cleared patches of land due to agricultural activity. Photo by Amanda Vicente.

A growing number of studies show a similar pattern linking the destruction of tropical forests with disease reemergence, Gillespie says, including a reemergence of hanta viruses in the Amazon associated with soybean production and the reemergence of the Lassa virus in West Africa, linked to oil-palm production. 

In a previous study, the researchers and colleagues showed that shifts in the feeding preferences of vampire bats due to human land-use changes in Costa Rica altered the gut microbial communities and immune systems of the bats. Such shifts could potentially make bats more susceptible to pathogens and more likely to spread them. 

“When governments make decisions about large-scale land-use changes, they need to consider the potential of disease emergence, or reemergence, along with the potential for increased greenhouse-gas emissions,” Gillespie says. 

In addition to their association with the destruction of natural habitat, cows and other ruminant animals emit methane, a potent greenhouse gas, as they digest grasses. And the greenhouse gas nitrous oxide is emitted from the manure of ruminants. 

“As an individual, you may want to reduce beef in your diet as much as possible,” Gillespie says, “both to improve your own health and that of the planet. We are currently using natural resources at a rate that’s not sustainable.” 

First author of the current paper is Christie Jones, who did the work as a student in Emory’s 4+1 BS/MPH program, where she received a bachelors in environmental sciences before entering an accelerated program for a master of public health at Rollins School of Public Health. Jones is currently studying medicine at the American University of the Caribbean. Amanda Vicente, a former Emory postdoctoral fellow in the Gillespie lab who is now at the University of Oklahoma, is a co-author. 

The work was funded by Emory University’s Halle Institute for Global Research, the Department of Environmental Sciences and the Fox Center for Humanistic Inquiry, and the Fulbright Association.

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