A snapshot of scientific thought on emotions in animals

Wild capuchin monkeys in Costa Rica where Emory anthropologist Marcela Benítez is studying their social behaviors. (Capuchinos de Taboga)

The journal Royal Society Open Science published a survey of 100 researchers of animal behavior, providing a unique view of current scientific thought on animal emotions and consciousness. 

“As far as we know, this is the first assessment of how animal behavior researchers across a range of disciplines think about emotions and consciousness in non-human animals,” says Marcela Benítez, assistant professor of anthropology at Emory University and corresponding author of the paper. “It gives us a snapshot in time so that 20 years from now, we can revisit how scientific experts may have changed their views.” 

A majority of the survey respondents ascribed emotions to “most” or “all or nearly all” non-human primates (98%), other mammals (89%), birds (78%), octopus, squids and cuttlefish (72%) and fish (53%). And most of the respondents ascribed emotions to at least some members of each taxonomic group of animals considered, including insects (67%) and other invertebrates (71%). 

The survey also included questions about the risks in animal behavioral research of anthropomorphism (inaccurately projecting human experience onto animals) and anthropodenial (willful blindness to any human characteristics of animals). 

“It’s surprising that 89% of the respondents thought that anthropodenial was problematic in animal behavioral research, compared to only 49% who thought anthropomorphism poses a risk,” Benítez says. “That seems like a big shift.” 

Anthropomorphism, she notes, has long been a leading argument against those who attributed feelings to animals.

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Chemists showcase power of pathbreaking method to make complex molecules

"We've had tremendous impact on developing C-H functionalization as both an academic discipline and for industry applications," says Emory chemist Huw Davies, who brought researchers from 15 universities together under the umbrella of the NSF Center for C-H Funcitonalization.

Chemists synthesized a highly complex natural molecule through a revolutionary strategy of functionalizing normally inert carbon-hydrogen (C-H). Science published the breakthrough led by chemists at Emory University and Caltech. 

The work is the most dramatic example yet of a sequence of C-H functionalization reactions selectively transforming low-cost materials into complex building blocks of organic chemistry. Ten of the steps involved in their synthesis of cylindrocyclophane A — a natural compound with antimicrobial properties — involved C-H reactions. 

“It’s by far the most complex natural product we have made using our method,” says Huw Davies, Emory professor of chemistry and co-corresponding author of the paper. “This is a game changer. We’re doing chemistry on C-H bonds that formerly would have been considered as unreactive. And we’ve shown how we can orchestrate a suite of 10 C-H functionalization steps, targeting a single C-H bond at a time in a specific sequence.” 

“This work moves the field forward by showing the power of C-H functionalization,” adds Brian Stoltz, professor of chemistry at Caltech and co-corresponding author of the paper. “It will open people’s eyes to the possibilities of using these very selective and unusual transformations in a really complex setting.” 

First author is Aaron Bosse, who did the work as an Emory PhD student. Bosse has since graduated and is now a medicinal chemist at Takeda Pharmaceuticals in Cambridge, Massachusetts.

Read the full story here.

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Bacterial pathogen shows alarming resistance to common cleaners, chemists discover

A new study reveals widespread resistance of a major bacterial pathogen to the active ingredients in cleaning agents commonly used in hospitals and homes. 

The American Chemical Society Infectious Diseases published the research led by chemists at Emory University. It demonstrates the surprising level of resistance to cleaning agents of multidrug-resistant Pseudomonas aeruginosa, a pathogen of particular concern in hospital settings. 

The study also identifies biocides that are highly effective against P. aeruginosa, including a novel compound developed at Emory in collaboration with Villanova University. The researchers describe how these biocides work differently than most disinfectants currently in use. 

“We hope our findings can help guide hospitals to reconsider protocols for the sanitation of patient rooms and other facilities,” says William Wuest, Emory professor of chemistry and a senior author of the study. “We also hope that our findings of a new mechanism of action against these bacterial strains may help in the design of future disinfectant products.” 

First authors of the study are Christian Sanchez (who did the work as an Emory PhD student in chemistry and, following graduation, joined the faculty at Samford University) and German Vargas-Cuebas, an Emory PhD candidate in microbiology through Laney Graduate School. 

“Resistance of pathogens to cleaning agents is an area that’s often overlooked,” Vargas-Cuebas says, “but it’s an important area of study, especially with the rise in antibiotic-resistant pathogens worldwide.”

Read the full story here.

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Exploring the nature of fathers

"My academic life informed my personal life and vice versa as I wrote the book," Rilling says. "It was an interesting interplay." (Photo by Kay Hinton)

In a new book, James Rilling interweaves his personal experiences as a son, husband and dad with the latest scientific insights into fatherhood. The MIT Press published “Father Nature: The Science of Paternal Potential.” 

“It’s about how and why human males evolved the capacity to be involved caregivers, how that care benefits their children, and the circumstances in which it is more common,” says Rilling, a professor in Emory University’s Department of Psychology and Department of Psychiatry and Behavioral Sciences. “The intended audience is anyone who is, has or knows a father.” 

Rilling explores the neural basis of human social cognition and behavior as the director of the Laboratory for Darwinian Neuroscience. Around the time of the birth of his first child, he realized that paternal caregiving was a neglected research topic and he decided to make it a focus of his lab. 

He also began teaching an undergraduate course on fatherhood.

Read the full story here.

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Spiny Mice Point to New Path in Neuroscience

Spiny mice live in arid environments in Africa, the Middle East and southern Asia.

By Carol Clark

Scientists zeroed in on brain circuitry powering the desire of spiny mice to live in large groups, opening the door to a new model for the study of complex social behaviors in mammals. 

Current Biology published the work led by researchers at Emory University. It shows that neural signaling from the brain’s anterior cingulate cortex to the lateral septum drives the preference for spiny mice (Acomys) to affiliate with large peer groups. 

“To our knowledge, this is the first study to identify neural circuitry that promotes group-size preferences in a mammal,” says Aubrey Kelly, senior author of the study and associate professor of psychology at Emory. “We hope that our work paves the way for new insights into complex social behaviors in a range of mammals, including humans.” 

The Kelly lab made the breakthrough by developing methods to use spiny mice as a laboratory model for social neuroscience. 

Read the full story.

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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.

Read the full story here.

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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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Identifying risks of human flea infestations in plague-endemic areas of Madagascar

A home in the Central Highlands of Madagascar. Residential structures vary greatly in rural areas. (Photos by Adelaide Miarinjara)

By Carol Clark

Madagascar is one of the last places where outbreaks of human bubonic plague still happen regularly. 

Fleas carrying the plague bacterium Yersinia pestis can spread the disease through their bites. And while a species commonly known as “the rat flea” has been fingered as the main culprit in plague outbreaks, a species known as “the human flea” may play a secondary role. 

As an investigator during plague outbreaks in rural Madagascar, medical entomologist Adelaide Miarinjara knew that many households were teeming with these human fleas. Miarinjara grew up in the island nation off the east coast of Africa and is now a postdoctoral fellow at Emory University, collaborating with the Pasteur Institute in Madagascar. 

“We have observed huge variability in the number of fleas in different households in the same village,” she says. “We might collect three or five fleas in one house and hundreds of them in another house.” 

Miarinjara led a study to solve the mystery of this variability. 

PLoS Neglected Diseases published her team’s findings: The abundance of human fleas is primarily associated with households that have a traditional dirt floor covered by a plant-fiber mat, as opposed to households with cement or board floors. A secondary risk factor was keeping animals in the house at night. 

“Flea larvae need humidity, but not too much humidity, to survive,” Miarinjara says, “so the dirt covered by the plant-fiber mat may be holding just the right amount of moisture for them to thrive.” 

She hopes that agencies seeking to improve people’s lives in plague-endemic areas of Madagascar focus on upgrading the flooring in homes and constructing sheds separate from the households for animals.

“Flea infestation raises the risk for getting diseases and it has a big impact on the quality of life,” Miarinjara says. “The constant bites are annoying and lead to lack of sleep.” 

Household flea infestations also promote the overuse of insecticides. Surveys by the researchers reveal that 80% of the households use insecticide to try to battle the fleas. Many people are buying liquid insecticides that are repackaged in empty plastic or glass containers, without labels or instructions for how to apply them, and sold in small, open-air markets. 

Improper use of insecticides is a health risk to people who may be overexposed to the chemicals.

“Overuse of these chemicals is also dangerous because some fleas are developing resistance to insecticides — the frontline tools for battling plague outbreaks,” Miarinjara says. 

“Poverty related to housing construction is a primary challenge that this research identified,” adds Thomas Gillespie, senior author of the study and professor and chair of Emory’s Department of Environmental Sciences. “Resurfacing dirt floors in homes with concrete could improve a range of health and quality-of-life issues, from reducing flea populations in homes to making the floors easier to clean of contaminants such as fecal matter tracked in from the outside.” 

The Gillespie lab is a pioneer in the “one health” approach to epidemics — studying the interactions of people, domestic animals, wildlife and ecosystems to understand how germs jump across species. 

Village residents gather to hear the research team brief them on the purpose of their visit. The women in the foreground are sitting on a traditional plant-fiber mat.

The plague has afflicted humans at least as far back as the Bronze Age and has persisted through the centuries. The advent of antibiotics — which can effectively treat plague — turned the disease into a horror story from the past for much of the world. 

In Madagascar, however, plague returns regularly to claim new victims. Cases typically originate in the rural rice-growing region of the central Highlands during the rainy season. Outbreaks there are associated with agriculture, deforestation, the black rat — and fleas. 

Different flea species have evolved to prefer the blood of one animal over another, although they may feed on a variety of organisms if they are hungry enough. 

Most plague research is centered on the rat flea, or Xenopsylla cheopis. Just one of its bites can transmit enough bacteria to infect someone with plague. In contrast, several bites from the human flea, Pulex irritans, are required to transmit the bacteria, making it a less potent spreader of plague but still a threat. 

For the current paper, the researchers collected fleas from 126 households in four different villages. Rural Madagascar homes typically consist of more than one level. The bottom level is often used to keep livestock overnight and the second and third floors are where members of the family sleep, cook and eat. 

Researchers collect the fleas captured overnight in a candle trap while members of a household watch.

The fleas were collected overnight on the second floor of the homes using simple traps — a lit candle set in a dish of soapy water. The fleas are attracted to the flickering light and drown when they hop into the dish. 

The researchers painstakingly removed each drowned flea using tweezers, set them to dry on absorbent paper, and then transferred them to test tubes for laboratory identification and analyses. 

The results showed that around 95% of the species collected in households were human fleas, mixed at times with a few rat fleas and a few from a third species that prefers to feed on cats and dogs. Collections were conducted in both the dry and rainy seasons with similar results. 

“We’re now looking deeper into what’s going on with insecticide use in households,” Miarinjara says. “We want to both sort out what is driving insecticide resistance among fleas and find ways to help people use insecticides safely and more effectively.” 

Co-authors of the current study include: Annick Reveloson, a PhD student at the University of Antananarivo in Madagascar; Stephen Mugel, an Emory PhD student set to graduate this May; Nick An, who graduated last year from Emory’s BS/MPH program; Andry Andriamiadanarivo, a technician at Centre ValBio in Madagascar; and Minoarisoa Rajerison, Rindra Randremanana and Romain Girod, research scientists at the Pasteur Institute in Madagascar. 

The research was funded by the Branco Weiss Society in Science Fellowship and the American Society of Tropical Medicine and Hygiene.

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Tracking ticks in Georgia to help monitor emerging diseases

Mapping the lone star tick is another step in a comprehensive Emory project to track and monitor the array of tick species in Georgia and the diseases that they can spread — including those caused by emerging pathogens.

By Carol Clark 

The most common tick found on humans in Georgia is the lone star tick — an aggressive seeker of blood that can spread dangerous pathogens through its bites. 

Emory University researchers combined field data with spatial-analysis techniques to map the distribution of the lone star tick across the state. The journal Parasites & Vectors published the research, which identifies specific environmental conditions associated with this tick species, Amblyomma americanum, in Georgia. 

The areas with the highest probability for the presence of lone star ticks include parts of the Southeastern Plains and Piedmont ecoregions of the state, including metro Atlanta. 

“We found that these regions contain sweet spots for the lone star tick,” says Stephanie Bellman, first author of the study and an MD/PhD student in Emory’s School of Medicine and Rollins School of Public Health. “They tend to be more prevalent in forested areas of mid-elevation — not too high or too low — and in soils that retain moisture but are not swampy.” 

The study maps the distribution at the scale of one square kilometer. That resolution is far finer than the currently available information, which is limited to the county level and does not encompass the state. 

“As the weather warms and people start getting into the outdoors more, we hope our data can be used to target areas for tick-bite prevention messaging,” says Gonzalo Vazquez-Prokopec, professor in Emory’s Department of Environmental Sciences and senior author of the study. 

Vazquez-Prokopec is a leading expert in vector-borne diseases — infections transmitted among humans and animals by the bite of a living organism, such as a tick or a mosquito. 

Diseases the lone star tick is known to transmit include ehrlichiosis, southern tick-associated rash illness (STARI) and Heartland virus disease — which was first identified in the United States in 2009. The bite of the lone star tick is also associated with a potentially life-threatening allergy to red meat and dairy products known as alpha-gal syndrome. 

First author Steph Bellman, far right, in the field last summer with fellow Emory students and co-authors, from left, Josie Pilchik, Isabella Roeske, Ellie Fausett and Audrey Long.

Mapping the lone star tick is another step in a comprehensive Emory project to track and monitor the array of tick species in Georgia and the diseases that they can spread — including those caused by emerging pathogens. 

Tickborne diseases are on the rise, far surpassing the incidence of diseases spread by mosquitos in the United States. While Lyme disease is the most common, the Centers for Disease Control and Prevention (CDC) currently recognizes 18 tickborne diseases in the country. 

“We need to educate people that the environment that they grew up in is likely very different in terms of the number and types of ticks and the pathogens that they are carrying,” Vazquez-Prokopec says. 

Anne Piantadosi, assistant professor in Emory School of Medicine’s Department of Pathology and Laboratory Medicine, is co-author of the study. Co-authors also include five Emory students who conducted fieldwork: Ellie Fausett (who has since graduated with a joint environmental sciences/MPH degree); Leah Aeschleman and Audrey Long (who have since received master’s of public health degrees from Rollins School of Public Health); Josie Pilchik, (who graduated with a bachelor’s in biology) and Isabella Roeske (an Emory senior majoring in environmental sciences). 

Climate change is fueling warmer and shorter winters, increasing opportunities for some species of ticks to breed more frequently and expand their ranges. Land-use changes are also strongly associated with tickborne diseases, as more human habitats encroach on wooded areas and the loss of natural habitat forces wildlife to live in denser populations. 

“Georgia is a tick haven in general,” Bellman says, “since we have a long warm season and such a diversity of habitats.” 

An aggressive biter

The researchers decided to focus first on mapping the distribution of the lone star tick because it is the dominant tick species in Georgia and can spread an array of pathogens. In 2019, the Emory researchers found that Heartland virus is circulating in lone star ticks in Georgia, an emerging pathogen that is not well understood. 

The lone star tick (CDC)

Named for a bright, yellowish-white spot on its back, the lone star tick is widely distributed in wooded areas across the Southeast, Eastern and Midwest United States. It is tiny —in the nymph stage it is about the size of a sesame seed and as an adult it is barely a quarter-of-an-inch in diameter as an adult.

Despite its tiny size, the lone star tick is aggressive in its quest for blood meals. “They can sense carbon dioxide from your exhaled breath and the vibrations from your movement in a forest,” Bellman says. “They climb up onto vegetation and reach out their legs to grab onto you as you pass by.” 

For the current study, Bellman led crews of Emory students, known as “the tick team,” in field surveys. They used “flagging” as a tick-collection technique. A white flannel cloth attached to a pole is swished in a figure-eight motion through the underbrush. Tweezers are used to transfer any ticks found on the flannel into a vial. 

Tick team members surveyed 198 locations at 43 state parks and wildlife management areas across the state, from March to July 2022. Analyses combined the site-sampling data with environmental variables — including type of vegetation, land use, climate, elevation and other factors — characteristic for six different ecoregions of Georgia. 

Lone star ticks were found in all of the ecoregions except for the mountainous Blue Ridge ecoregion in the northeast corner of the state. The majority of the ticks were found in forested areas of the Piedmont, Southeastern Plains and Southern Coastal Plains ecoregions. 

The researchers encourage people to follow the recommendations of the CDC for preventing tick bites. 

An array of ticks

And while the map for the lone star tick provides guidance on the likelihood of encountering the most prevalent human-biting tick in the state, there are other tick species that the researchers have yet to map. The black-legged tick (Ixodes scapularis), which can transmit the bacterium that causes Lyme disease, for instance, is also established in Georgia. Lyme disease, however, is relatively uncommon in in the state for reasons that are not yet well-understood. 

The researchers are also investigating the Asian longhorned tick (Haemaphysalis longicornis) in Georgia. Long established in China, Japan, Russia and parts of the Pacific, the Asian longhorned tick was first detected in the United States in 2017, in New Jersey, and has since spread to 19 states. It was found on farm animals in Pickens County, Georgia in 2021. 

The Asian longhorned tick (CDC)

The Asian longhorned tick reproduces asexually and a single female can generate as many as 100,000 eggs, rapidly producing massive amounts of offspring that feed on livestock. So many ticks can be covering a single sheep or cow that the loss of blood physically weakens or, in extreme cases, kills the animal. 

While it is often associated with livestock, the Emory research team recently found Asian longhorned ticks in the Buck Shoals Wildlife Management Area in White County, Georgia. 

The Asian longhorned tick carries bacterial and viral pathogens that can infect humans, including severe fever with thrombocytopenia syndrome virus (SFTSV), also known as Dabie bandavirus. Human cases of SFTS, a hemorrhagic fever, emerged in China in 2009 and have since been identified in other parts of Asia, although not in the United States. 

Also of concern is the fact that the Heartland virus shares genomic similarities with SFTS, which suggests the Asian longhorn tick could potentially transmit this emerging pathogen. The Emory team has been finding the Heartland virus in lone star ticks collected from central Georgia starting in 2019. They have continued to find Heartland virus in at least some of the ticks collected from that area nearly annually through 2023. (They did not perform collections in 2020 due to the COVID-19 pandemic.)

More than 60 cases of Heartland virus disease have been reported in the United States, according to the latest CDC statistics. Many of the identified cases were severe enough to require hospitalization, and a few individuals with co-morbidities have died. The actual number of people who may have been infected with Heartland virus is believed to be higher, however, since the virus is not well known and tests are rarely ordered for it. 

Complicating the issue is the fact that symptoms of Heartland virus are akin to those of many tickborne illnesses: fever, fatigue, headache, nausea, diarrhea and muscle or joint pain. 

“Human cases of Heartland virus are rare now, but we don’t know whether that could change,” Bellman says. “We need to gather more baseline data and learn how it spreads in the environment so that we have the evidence we need to potentially prevent, or limit, its spread.” 

Anne Piantadosi, assistant professor in Emory School of Medicine’s Department of Pathology and Laboratory Medicine, is co-author of the study. Co-authors also include five Emory students who conducted fieldwork: Ellie Fausett (who has since graduated with a joint environmental sciences/MPH degree); Leah Aeschleman and Audrey Long (who have since received master’s of public health degrees from Rollins School of Public Health); Josie Pilchik, (who graduated with a bachelor’s in biology) and Isabella Roeske (an Emory senior majoring in environmental sciences). 

Work on the current paper was funded by grants from the U.S. Department of Agriculture, National Institutes of Health, Emory University and the Emory MP3 Initiative and Infectious Disease Across Scales Training Program. 

Related stories: 

Heartland virus identified in lone star ticks in Georgia 

Building boom boosts malaria-carrying mosquito in Ethiopia 

Big data zeros in on a mosquito menace

A new estimate of U.S. soil organic carbon to improve Earth system models

"To understand how soil carbon will change under a changing climate, we first need accurate estimates of current soil organic carbon levels and the key factors that influence them," says Emory environmental scientist Debjani Sihi, senior author of the study.

By Carol Clark

Soil contains about twice as much carbon as the atmosphere and plants combined. It is a major carbon sink, capable of absorbing more carbon dioxide from the atmosphere than it releases. Management of soil carbon is key in efforts to mitigate climate change, in addition to being vital to soil health and agricultural productivity. 

Measuring soil carbon, however, is a painstaking, expensive process. Samples must be dug from the ground and sent to a lab for analysis, making upscaling measurements on a large spatial scale challenging. 

Now environmental scientists have combined field-level data with machine-learning techniques to estimate soil organic carbon at the U.S. continental scale. The Journal of Geophysical Research — Biogeosciences published the new soil organic carbon estimate, which improves the overall estimate for the United States and gives new insights into the effects of environmental variables on soil organic carbon. 

“There is growing recognition that soil organic carbon is important and that we should invest in building it up through sustainable land management practices,” says Debjani Sihi, senior author of the study and assistant professor of environmental sciences at Emory University. “Our estimate is more accurate than existing estimates and provides a better benchmark to guide policymakers and land managers in adopting climate-smart practices.” 

Land is far more efficient than the ocean at retaining carbon, Sihi notes, and offers one possible nature-based solution to help mitigate climate change. “We could potentially create conditions,” she explains, “that are favorable for soil to capture carbon dioxide from the atmosphere and lock it there for a really long time — over millennia.” 

Sihi is a biogeochemist who studies environmental and sustainability issues at the nexus of soil and climate. 

First author of the current paper is Zhuonan Wang, a former postdoctoral fellow in Sihi’s lab who is now at Colorado State University. 

Digging into soil data 

Soil organic carbon is made up of plant and animal matter in various states of decomposition. While inorganic carbon is also found in the soil in the form of carbonate minerals, organic carbon is usually the largest proportion and the most important driver of soil biology and quality. 

The U.S. Department of Agriculture maintains the National Cooperative Soil Survey soil characterization database. This data was gathered over decades both by walking over the land and observing and by digging up core samples and sending them to laboratories for analysis. Measuring soil organic carbon, for example, requires digging a core to the root zone, about 30 centimeters deep to obtain a topsoil profile and until the core hits bedrock to obtain an entire soil profile. 

Soil sampling is done in other parts of the world as well. The International Soil Organic Carbon Network encompasses more than 430,000 soil profiles, drawn from across the globe. Scientists use such data to create “soil maps,” or estimates of soil characteristics in various regions. One well-known soil map is the Harmonized World Soil Database, developed by the United Nations’ Food and Agricultural Organization and collaborators. Another is SoilGrids, supported by the International Soil Reference and Information Center in the Netherlands. 

Significant inconsistencies exist in the estimates of soil organic carbon within both the Harmonized World Soil Database and SoilGrids. Sihi and her team set out to see if they could resolve these inconsistencies within the United States estimates by finding more effective ways to scale up the soil-sampling data. 

The researchers divided the United States — including all 50 states and Puerto Rico — into 20 different regions and created machine-learning models for each region. They obtained nearly 50,000 soil samples, ranging from 30 centimeters to one meter deep, from across these regions. They built their algorithms using these data samples for soil organic carbon, matched to precise geographic information system locations. 

They also drew from additional open-source data to feed their models with 36 environmental variables, including details about the climate, topographical features of the land, biogeochemical properties of the soil and the amount of vegetation on the landscape. 

A better benchmark for modeling Earth systems 

The results showed that the new method provided more accurate estimates than both the Harmonized World Soil Database and SoilGrids for the top 30 centimeters of soil, where the most biologically active soil organic carbon tends to be concentrated. 

The new method also revealed how the effects of environmental variables on soil organic carbon vary across regions. While climate was the most common predictor of soil organic carbon across most of the regions, the vegetation index tended to be more important in the arid areas of the southwest. Elevation was a key variable in regions that were mountainous or included a major river delta. 

The researchers hope that others will apply their approach to other countries and continents where enough on-the-ground data is available. 

“The beauty of our approach is that it gives us the power to identify regions with high uncertainty in our estimates and that helps us to guide future sampling efforts,” Sihi says. 

Considering environmental variables also increases the new model’s flexibility as global temperatures rise due to climate change, causing soils to warm and alter rainfall patterns. It remains unclear, Sihi notes, if soils will continue to serve as a carbon sink or transform into a carbon source. 

“To understand how soil carbon will change under a changing climate, we first need accurate estimates of current soil organic carbon levels and the key factors that influence them,” Sihi says. “Our new estimate is a step toward getting more accurate baseline data to improve Earth system models for climate change.” 

Co-authors of the new estimate include Jitendra Kumar (Oak Ridge National Laboratory), Samantha Weintraub-Leff (National Ecological Observatory Network), Katherine Todd-Brown (University of Florida) and Umakant Mishra (Sandia National Laboratories). 

The work was supported by the National Science Foundation and the U.S. Department of Energy.

Related:

Emory breaking new ground for climate-smart agriculture in Southeast

Soil quality critical to help some U.S. crops weather heat stress from climate change

Paint color-matcher quantifies iron levels in soil

'Jeopardy!' contestant creates buzz with psychological study of trivia experts

'Jeopardy!' contestant and Emory psychologist Monica Thieu, shown with host Ken Jennings, during the 2024 "Jeopardy!" Invitational Tournament.

Monica Thieu is a four-time "Jeopardy!" contestant and a postdoctoral fellow in Emory's Department of Psychology. Psychonomic Bulletin & Review recently published her finding that two memory systems — one for facts and another for personal experiences  are more entwined in the minds of top trivia experts compared to others. 

"In trivia experts, it appears that these two systems are talking to each other in unique ways," Thieu says. "Our findings for this special population may help us better understand how memory works in normative populations."

Thieu says her personal experience in trivia competitions helped in the design of the study. 

"It's trick to make sure that lab experiments are both rigorous and reflect lived experience," Thieu says. "I know the world of trivia experts well."

Read the full story here.

Related:

Psychologists document the age our earliest memories fade

Primatologist Frans de Waal remembered for bringing apes 'a little closer to humans'

Frans de Waal shown overlooking the chimpanzee habitat at the Emory National Primate Research Center.

By Carol Clark

Emory University primatologist Frans de Waal — who pioneered studies of animal cognition while also writing best-selling books that helped popularize the field around the globe — passed away March 14, 2024, from stomach cancer. 

De Waal, Charles Howard Candler Professor Emeritus of Psychology and former director of the Living Links Center for the Advanced Study of Ape and Human Evolution at the Emory National Primate Research Center, was 75. From his groundbreaking 1982 book “Chimpanzee Politics: Power and Sex Among Apes” to 2019’s “Mama’s Last Hug: Animal Emotions and What They Tell Us About Ourselves,” de Waal shattered long-held ideas about what it means to be an animal and a human. 

“One thing that I’ve seen often in my career is claims of human uniqueness that fall away and are never heard from again,” de Waal said in 2014. “We always end up overestimating the complexity of what we do. That’s how you can sum up my career: I’ve brought apes a little closer to humans but I’ve also brought humans down a bit.” 

 Read the full story here by clicking here.

Atlanta Science Festival returns to inspire discovery for all ages

A middle-school student experiences an Emory chemistry lab during a recent community outreach event. 

The Atlanta Science Festival returns March 9 to 23, inviting curious kids and adults to explore all things science, technology, engineering and mathematics (STEM). Experts in these fields — including many members of the Emory community — will serve as educational guides for more than 150 interactive events. 

“The Atlanta Science Festival aims to bring the community together through their shared love of science,” says Meisa Salaita, co-founder and co-executive director of Science ATL, the engineers of the festival. “Through these events, we hope to inspire and empower the next generation to pursue their dreams.” 

Participants can take a crash course on the basics of AI, create an herbarium of medicinal plants, go into the field with researchers studying microplastic pollution in a stream, take a behind-the-scenes tour of the latest advances in healthcare technology and even get a taste of the physics of cheese making. 

Now in its 11th year, the Atlanta Science Festival was co-founded by Emory, Georgia Tech and the Metro Atlanta Chamber. 

“We have grown into a mainstay of Atlanta,” says Salaita, noting that many of the events fill up quickly. “The festival is something that people look forward to every spring.” 

 Click here for highlights of this year's festival with an Emory connection.

Spatial model predicts bumblebee exposure to pesticide use

Field experiments were conducted using yellow-faced bumblebees, a species native to the West Coast and an important pollinator.

By Carol Clark

It has long been known that agricultural pesticides are one of the greatest threats to bees and other essential pollinators. What farmers have lacked is an understanding of how different pesticides, applied at various times on a variety of crops, affect the risk of exposure to bees living near the fields. 

Researchers have drawn from real-world data to try to address this gap, developing and testing a spatial model for predicting pesticide exposure in bumblebees. The journal Science of the Total Environment published the work, based on the interactions of the yellow-faced bumblebee (Bombus vosnesenskii) with crops in California. 

“We were able to explain nearly 75% of the spatial variation in pesticide exposure among the bumblebee hives using our model,” says Eric Lonsdorf, first author of the study and assistant professor in Emory’s Department of Environmental Sciences. 

Relatively simple models were more effective at preventing exposures than the researchers expected.

“Our results suggest that simply data on where and when a pesticide was sprayed is all that you need to make a good prediction for the threat to nearby hives,” Lonsdorf says. 

Including data on how long a particular chemical lingers in the landscape or how attractive the flowers in a particular crop are to the bees did not make a significant difference in the model’s predictive power. 

“We found that even if a crop is not that attractive to the bees, the chemicals from that crop are still going to be found in their pollen,” Lonsdorf says. “The bees may be picking up the chemical due to drift of the pesticide onto nearby weeds where they are foraging.” 

Providing tools for conservation 

Lonsdorf studies natural capital, or nature’s contributions to humans. He translates ecological principles and knowledge into predictive models that enable industry leaders and policymakers to better manage natural resources. 

He’s currently using models he developed to help the U.S. Fish and Wildlife Service identify bee conservation priority areas in the United States. 

More research is needed, Lonsdorf says, to determine whether the bumblebee risk-prediction model will scale up across different landscapes and for different species of bees. The current study also did not delve into how the amount of a particular pesticide found in the pollen translated into toxicity for the bees. 

Co-authors of the paper include Neal Williams from the University of California, Davis, and Maj Rundlöf and Charlie Nicholson, who are affiliated with the University of California, Davis, and Lund University in Sweden. 

Drawing from fine-scaled data 

The researchers began with experiments set amid a variety of crops in northern California’s Yolo County. Fourteen pairs of yellow-faced bumblebee colonies were placed around the agricultural landscape. This species of bumblebee is native to the West Coast and the most abundant wild species of bee in this range, found in both urban and agricultural areas. 

Pollen that bees in each hive collected were sampled at six different times during the growing season. The pollen samples were then assessed for exposure to 52 different active ingredients encompassing a range of pesticides. 

Data from these experiments were combined with field-level data from the California Department of Pesticide Regulation on what pesticides were sprayed and what days they were sprayed. 

“California is unique in providing such fine-scaled, public data,” Lonsdorf says. “In most places in the United States, information on what pesticides are being sprayed is only collected at the county level and summarized on an annual basis.” 

The detailed data allowed the researchers to consider a range of factors in their predictive model to identify those factors with the most predictive power. 

“Our risk-prediction model marks another step toward evaluating pollinator-conservation issues to help guide policies for pollinator landscapes,” Lonsdorf says. “The next step is to do a field-toxicity assessment to get a better understanding of how pesticides are affecting bee health.” 

He and colleagues are now conducting such a study with honeybees, he adds. 

The current paper was supported by the National Science Foundation, California Department of Food and Agriculture, Almond Board of California, KIND Foundation Fund for Pollinator Health and the Swedish Research Council.

Related:

Analyzing ways to help golden eagle populations weather wind-energy growth

Antibiotic used on food crops affects bumblebee behavior, lab study finds

Pollinator extinctions alter structure of ecological networks