Whole genomes map pathways of chimpanzee and bonobo divergence

A bonobo in the wild. "Understanding the physiological mechanisms underlying the differences in chimpanzee and bonobo behaviors may also give us information about the genes underlying our own behaviors," says Emory anthropologist John Lindo. (Photo by Sarah Kovalaskas)

By Carol Clark

Chimpanzees and bonobos are sister species that diverged around 1.8 million years ago as the Congo River formed a geographic boundary and they evolved in separate environments. Now, a whole-genome comparison of bonobos and chimpanzees reveals the gene pathways associated with the striking differences between the two species’ diets, sociality and sexual behaviors. 

The journal Genes, Brain and Behavior published the comparative analysis, conducted by anthropologists at Emory University.

 

“Our paper is the first whole-genome positive selection scan between chimpanzees and bonobos,” says John Lindo, Emory assistant professor of anthropology and senior author of the study. “We contrasted the genomes of both species to understand how natural selection has shaped differences between the two closely related primates.”  

 

Lindo is a geneticist specialized in ancient DNA and natural selection. “Chimpanzees and bonobos are fascinating because they are very, very closely linked genetically but they have huge behavioral differences,” he says.

 

The two species also share around 99 percent of human DNA, making them our closest living relatives in the animal kingdom. “Understanding the physiological mechanisms underlying the differences in chimpanzee and bonobo behaviors — particularly the much stronger propensity of bonobos toward conflict resolution instead of fighting — may also give us information about the genes underlying our own behaviors,” Lindo says.

 

Sarah Kovalaskas, an Emory graduate student of anthropology, is first author of the paper. Before joining Emory she spent nine months in the field, studying the social development of juvenile bonobos in the Democratic Republic of Congo (DRC). Wild bonobos, an endangered species, are only found in forests south of the Congo River in the DRC.

 

“Bonobos are well-known for being playful, even as adults,” Kovalaskas says. “It was fun to observe the juveniles twirling around in the trees, chasing one another and trying to pull each other down. When the mothers tried to wean them, they would sometimes throw tantrums and scream and run around. You can’t help but recognize the similarity in behaviors to humans.” 

Emory graduate student Sarah Kovalaskas in the field in the Democratic Republic of the Congo.

 

Populations of chimpanzees, also an endangered species, are found in a forested belt north of the Congo River and scattered in a few other areas of west and central Africa. 

 

Bonobos and chimpanzees closely resemble one another physically and they were not recognized as separate species until the 1930s. Their behavioral differences are much more distinct. While bonobos organize into female-led societies, chimpanzees are patriarchal. When bonobos encounter other bonobo groups they generally interact peacefully. Bonobos are also known for using sexual behaviors to defuse tension — including same-sex behaviors among females. Chimpanzees, however, tend to act more aggressively when encountering other chimpanzee groups and may even have violent exchanges that include fatalities. 

 

A leading hypothesis suggests that different feeding ecologies were key to the behavioral divergence between the two species. This theory posits that the abundant ground vegetation in the bonobo territory provided easy access to year-round food without competition from other individuals. Larger groups could feed together instead of foraging in isolation, allowing females to develop strong bonds to counter male domination, and to mate with less aggressive males, leading to a kind of “self-domestication.”

 

The whole genome comparison showed selection in bonobos for genes related to the production of pancreatic amylase — an enzyme that breaks down starch. Previous research has shown that human populations that began consuming more grains with the rise of agriculture show an increase in copies of a closely related gene that codes for amylase.

 

“Our results add to the evidence that diet and the available resources had a definite impact on bonobo evolution,” Kovalaskas says. “We can see it in the genome.”

 

Compared to chimpanzees, bonobos also showed differences in genetic pathways well-known to be related to social behaviors of animals — as well as humans. Bonobos had strong selection for genes in the oxytocin receptor pathway, which plays a role in promoting social bonds; serotonin, involved in modulating aggression; and gonadotropin, known to affect sexual behavior.

 

“The strong female bonds among bonobos, in part, may be mediated by their same-sex sexual behaviors,” says co-author James Rilling, professor and chair of Emory’s Department of Anthropology. “Our data suggest that something interesting is going on in the bonobo pathways for oxytocin, serotonin and gonadotropin and that future research into the physiological mechanisms underlying behavioral differences between bonobos and chimpanzees may want to target those specific systems.”

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First-known iguana burrow fossil discovered

An illustration of how the trace fossil of the iguana burrow (shown in cross-section) and the surrounding landscape may have looked during the Late Pleistocene Epoch. (Illustration by Anthony Martin)

The discovery of the first known fossil iguana nesting burrow, on an outer island of the Bahamas, fills in a gap of scientific knowledge for a prehistoric behavior of an iconic lizard. PLOS ONE published the finding by scientists from Emory University, which also uncovers new clues to the geologic and natural history of the Bahamas. 

The fossilized burrow dates back to the Late Pleistocene Epoch, about 115,000 years ago, and is located on the island of San Salvador — best known as the likely spot where Christopher Columbus made his first landfall in his 1492 voyage. 

“San Salvador is one of the outer-most islands in the Bahamas chain and really isolated,” says Anthony Martin, a professor in Emory’s Department of Environmental Sciences and senior author of the PLOS ONE paper. “It’s a mystery how and when the modern-day San Salvadoran rock iguanas arrived there. Today, they are among the rarest lizards in the world, with only a few hundred of them left.”

Martin’s specialty is ichnology — the study of traces of life, such as tracks, nests and burrows. He documents modern-day traces to help him identify trace fossils from the deep past to learn about prehistoric animal behaviors. 

Read the full story here.

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A new view of how the brain decides to make an effort

"The willingness to expend effort is something crucial to our survival that we use every day," says Emory psychologist Michael Treadway, senior author of the study.

Neuroscientists have provided clear visual evidence that a region of the human brain known as the ventral striatum kicks in during decision-making to weigh the costs versus the benefits of making a physical effort. 

Nature Human Behavior published the research by scientists at Emory University. It gives the first detailed view of ventral striatum activity during three phases of effort-based decision-making — the anticipation of initiating an effort, the actual execution of the effort and the reward, or outcome, of the effort. 

“It’s important to understand the neural mechanisms underlying motivation,” says Shosuke Suzuki, first author of the study and an Emory graduate student of psychology. “Our work has wide implications for treatment of disorders related to reduced motivation, such as depression, schizophrenia and PTSD. It may also help enhance motivational programs for everything from education to athletics and public health.”

Click here to read the full story.

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Valuing 'natural capital' vital to avoid next pandemic, global experts warn

Every economic decision needs to take natural capital into account to avoid an even bigger catastrophe than the current pandemic, says Emory disease ecologist Thomas Gillespie.

By Carol Clark

Pandemics will emerge more often, kill more people than COVID-19 and do even more damage to the world economy unless urgent steps are taken to address risk drivers such as deforestation, warns a major new report on biodiversity and pandemics. 

The report, entitled “Escaping the Era of Pandemics,” was made public by the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES), which includes United Nations members from more than 100 governments. The report is the result of an urgent workshop organized by the IPBES. The workshop brought together 22 experts to evaluate scientific evidence and make recommendations to control and prevent future pandemics, detailed in the report, which IPBES members will now consider whether to endorse. 

“The two biggest driving forces for pandemics are forest degradation and industrial animal production,” says Thomas Gillespie, an associate professor in Emory’s Department of Environmental Sciences and Rollins School of Public Health, who served as a scientific peer reviewer for the report. “Greater management and surveillance of wet markets, where live animals are sold, is also important.” 

Every major economic decision, Gillespie warns, needs to take into account what he calls “natural capital” in order to avoid even bigger catastrophes than the current pandemic. 

The economic costs of a major pandemic are 100 times the estimated costs of prevention, the report notes. It recommends government policy changes to reduce globalized agricultural expansion and the types of trade that have led to pandemics. Some of the possible measures it cites are taxing meat consumption and livestock production and reforming financial aid for land use to consider risks to biodiversity and health. 

Like all pandemics, the emergence of the novel coronavirus was driven entirely by human activities, the report states. The authors estimate that another 1.7 million currently “undiscovered” viruses exist in mammals and birds — and nearly half of them may have the potential to infect people. 

National governments need to incorporate a “One Health” approach — considering the deep connections between the health of people, domesticated animals, wildlife and ecosystems — to build pandemic control and prevention efforts, the report adds. 

Thomas Gillespie in 2018 with famed primatologist Jane Goodall. He is working with the Jane Goodall Institute on a One Health project in Tanzania's Gombe National Park.

Gillespie is a disease ecologist who helped pioneer the “One Health” approach to protect humans, ecosystems and biodiversity. His projects in Africa, including collaborating with Jane Goodall at Gombe National Park in Tanzania, are focused on helping farmers subsisting amid fragmented forests co-exist with primates and other wildlife in ways that minimize the risk of pathogen exchange between species, known as “spillover.” HIV, for instance, spilled over from chimpanzees to humans. Infectious disease and deforestation are the two biggest challenges facing chimpanzees at Gombe today, according to a newly published study led by Goodall and co-authored by Gillespie. 

The Gillespie Lab has a similar project in Costa Rica, focused on bats in fragmented natural ecosystems.

Now, Gillespie finds himself virtually managing his lab’s field projects while also advising global policymakers. “More people are listening,” Gillespie says. “This pandemic has fueled awareness that a One Health approach applied on a grand scale is vital to both local and global economies.” 

In the following Q&A, Gillespie explains the seismic shifts he says are needed to protect global health and economies against the impacts of pandemics. 

What do you mean exactly by “natural capital”? 

Natural capital consists of ecosystems of nature that sustain us. Human activity has driven an overall global decline in natural resources of 40 percent per capita in just over 20 years. Our economies, our health and our well-being are all built upon natural capital. 

There is growing recognition that we are totally dependent on the natural capital of our planet and that perpetual economic growth is not sustainable. We’ve had a false sense that we can simply measure the success of countries and policies through gross domestic product and economic growth, even when it means we are taking loans from nature that we have no capacity to repay. 

The rising risks of pandemics has caught the attention of people who are in charge of economies because COVID-19 is immediately affecting bottom lines. Every country is feeling the pain simultaneously, at both individual and national levels. 

Is it possible for human development and conservation to co-exist? 

When people talk about development from an economic standpoint it involves conversion of natural resources for profit, often by degradation of ecosystems via mining, timber cutting, oil extraction or clearing for cash crops. But when we talk about development from a sustainability perspective, we’re talking about improving the quality of human life. 

Use of the word “development” in these different ways can lead to a great deal of confusion. The urgency of the coronavirus pandemic is helping to break the silos down so that people from both camps can come together to think about solutions. There is growing recognition that instead of just considering whether a land-use project will impact a certain endangered species, we need to have mechanisms to evaluate more broadly how projects may impact the health of wildlife, people and an entire ecosystem. 

Right now, those profiting from economic development are not the ones paying the costs. The data shows very clearly that you can have a high GDP (gross domestic product) and also have plenty of poor people and a large proportion of a population struggling to survive. There is not a clear linkage between gains in the stock market and the quality of life for the average citizen. 

How does climate change fit into this “One Health” approach? 

Although many have rallied behind mitigating and adapting to climate change, it’s just one of the troubling vital signs of the planet. Climate change, biodiversity loss and the ever-increasing risks of pandemics are all symptoms of the same illness — our disconnect with nature and associated unsustainable norms. 

We’ve long needed to bring together climate scientists, disease ecologists and policymakers from agriculture, financial and environmental systems to tackle the illness instead of just having them all separately focus on individual symptoms. This shift is occurring, discussions are happening. The challenges are enormous, but at least now everyone has come together at the same table to try to work toward solutions. 

What are some examples of individual countries taking on these challenges? 

U.S. President-elect Joe Biden has vowed to rejoin the Paris Agreement for carbon reductions and set a 2050 carbon neutrality target. That holds huge implications for global climate diplomacy and will also create opportunities to rally behind shared solutions to prevent future pandemics and to safeguard the planet’s ecosystem services upon which our collective future depends. 

Some governments are beginning to remove environmentally harmful subsidies and redirecting incentives for a green recovery. In fact, New Zealand, Scotland and Iceland are recasting their entire economic frameworks to officially prioritize human well-being and planetary health over GDP. 

New Zealand developed a “Living Standards Framework” to set its budget. Bhutan now shapes policy to advance what it calls its “Gross Happiness Indicator.” Similarly, the world’s largest sovereign wealth fund — the Norwegian Government Pension Fund — has divested from 32 companies involved in unsustainable palm oil production. 

These kinds of initiatives are leading the way to build a better future together.

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Major review of plants' role in antibacterial activity clears new paths for drug discovery

"If ever there was a time to cultivate our knowledge and tap into the chemical power of plants, this is it," says ethnobotanist Cassandra Quave, noting that two in five plants are currently estimated to be threatened with extinction as a result of destruction of the natural world. (Getty Images)

By Carol Clark

Scientists have compiled the first comprehensive review of plant natural products that play a role in antibacterial activity, to serve as a guide in the search for new drugs to combat antibiotic-resistant pathogens. 

Chemical Reviews published the work by researchers at Emory University, which includes 459 plant natural products that met rigorous criteria for demonstrating antibacterial activity. The review is also deposited on the Shared Platform for Antibiotic Research and Knowledge (SPARK), sponsored by Pew Charitable Trusts. 

“We hope that chemists and pharmacology researchers will use our review as a guide to dig deeper into the promising potential of many plant compounds,” says Cassandra Quave, senior author of the review and associate professor in Emory’s Center for the Study of Human Health and Emory School of Medicine’s Department of Dermatology. Quave is also a member of the Emory Antibiotic Resistance Center. 

In the United States, at least 2.8 million people get antibiotic-resistant infections each year and more than 35,000 people die from them, according to the Centers for Disease Control and Prevention. 

“If ever there was a time to cultivate our knowledge and tap into the chemical power of plants, this is it,” Quave says. “We’re seeing a rise in antimicrobial resistance across the globe. And, at the same time, we’re also losing vast amounts of plant biodiversity.” 

Two in five plants are currently estimated to be threatened with extinction, according to the State of the World’s Plants and Fungi Report, published in 2020 by the Royal Botanic Gardens, Kew. 

Quave is a leader in the field of medical ethnobotany, studying how Indigenous people incorporate plants in healing practices to uncover promising candidates for new drugs. The Quave lab has identified compounds from plants such as the Brazilian peppertree, the American beautyberry and the European chestnut that inhibit dangerous antibiotic-resistant bacteria. Her lab found, for instance, that triterpenoid acids from the Brazilian peppertree “disarm” methicillin-resistant Staphylococcus aureus, known as MRSA, by blocking its ability to produce toxins. 

The first antibiotic, penicillin, was derived from microbes in mold that kill bacteria. Since then, scientists have found other microorganisms that live in soil that are easy to grow in a laboratory setting and can kill pathogens resistant to some drugs. The ability of bacteria to continue to evolve resistance, however, is outpacing the ability to generate effective drugs from these sources. 

“One obstacle to plant natural products making it into the new drug pipeline is the complexity of the discovery process,” Quave says. “You have to identify a promising plant candidate, tease through the hundreds of chemicals contained within a particular plant to identify the active compound, and then isolate enough of this compound to do experiments on it. It’s not nearly as easy as sequencing a soil microbe and growing up a big vat of it to conduct experiments.” 

Tapping the knowledge of traditional people who have used plants for centuries to treat infections offers valuable clues for where to focus research, she adds. 

“In recent decades, interest has grown in investigating plants as potential drug candidates,” Quave says. “Technologies have improved to more easily access and study bioactive molecules within plants. And more papers are being published that follow standardized procedures for evaluation of antimicrobial activities among plant compounds.” 

For the current review, the Quave lab looked at nearly 200 papers published between 2012 and 2019 that met strict standardization criteria for authenticating plant-derived compounds that significantly inhibited antibacterial activity. The co-authors spanned undergraduates who conducted the initial literature reviews to graduate students and scientists specialized in biology, chemistry, pharmacology and/or botany. 

The 459 compounds included in the review encompass a diverse range of species — including those from commonly known plant families such as citrus, daisies, beans and mint. The compounds fall into three major classes of chemicals: About half are phenolic derivatives, around 25 percent are terpenoids, nearly 6 percent are alkaloids and the remainder are classified as other metabolites. 

The co-authors selected 183 of the compounds and provided further discussion of their antibacterial activity, biosynthesis, chemical structure, mechanism of action and their potential as antibiotics. 

“These are all compounds as they appear in nature, not synthesized or derivatized by chemists,” Quave explains. “We wanted to provide a systematic overview that brings promising drug candidates to the forefront, opening up new chemical space for discovery. Our review can serve as a starting point for chemists to consider whether they could possibly optimize any of these compounds to become scaffolds for antibiotic treatments.” 

Co-authors of the review include the following members of the Quave lab: Gina Porras, a post-doctoral fellow specialized in natural products chemistry; François Chassagne, a post-doctoral fellow and a pharmacologist; James Lyles, an associate academic research scientist and analytical chemist; Lewis Marquez, a graduate student of pharmacology; Micah Dettweiler, a former research specialist in the lab who is now a graduate student in agronomy at the University of Florida; Akram Salam, a graduate student of pharmacology; Tharanga Samarakoon, a botanist and collections manager of the Emory University Herbarium; Sarah Shabih, an Emory senior majoring in human health; and Darya Farrokhi, who graduated from Emory in 2020 with a degree in biology. 

The work was supported by the National Institute of Allergy and Infectious Disease, the National Center for Complementary and Integrative Health, Emory University and The Jones Center at Ichauway in Georgia.

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Taking math by storm: Talea Mayo models how climate change may affect our coasts

"I use a computer to solve math problems surrounding the way that fluid moves during storms," says Emory mathematician Talea Mayo. "I don't study the atmosphere. I study the response of the ocean to the atmosphere."

By Carol Clark

Talea Mayo joined the Emory faculty in May as assistant professor in the Department of Mathematics. A computational mathematician, she specializes in developing numerical hydrodynamic models to help predict coastal hazards.  

By creating models for storm surge caused by hurricanes, for instance, she is able to investigate the potential impacts of climate change on coastal flood risks. The resulting data may help policymakers and others develop better plans for the safety and resilience of coastal communities. 

Among Mayo’s accolades are an Early-Career Research Fellowship from the National Academies of Sciences Gulf Research Program and the Early Career Faculty Innovator Award from the National Center for Atmospheric Research. 

In the following Q&A, Mayo talks about some of the environmental forces that helped shape her as a scientist and as an educator, and how she became what she describes as “a fierce advocate of accessible, inclusive science and education of all people.” 

You grew up in Littleton, Colorado. What were some of your early math and computer science influences? 

My mom was in software development and we always had a computer around. I don’t ever remember not having one nearby. Before I even started school, she bought me this really simple kid’s learning tool that was like a computer, with a keyboard and a screen. By the time I was in first grade, she was teaching me multiplication and I would practice on my “computer.” 

I liked school and most of the subjects. I especially liked that math and science subjects were objective. Your answer to a problem is either right or wrong. But I really thought I wanted to be a lawyer. 

How did you decide to attend Grambling State University in Louisiana? 

I wanted to go away somewhere different than Colorado. I applied to a few schools randomly but I got a scholarship to Grambling and so I went there. I loved being in the South. It was so green while Colorado is so dry. Also, Colorado’s population is about 4 percent Black. My experience with Black people was mainly limited to church and family. Grambling is an Historically Black College and University and probably 96 percent Black. It was nice to meet Black people from all over the country and from all different socio-economic backgrounds. I played the flute and piccolo and I joined Grambling’s famous marching band. The band is really tight knit and that made it easy for me to build community there. I really value that. 

I also valued how the professors interacted with students. I was a criminal justice major, but I took a high-level calculus class because math was important to me. The professor eventually called me into his office and said, “You should change your major to math.” I thought about it and I realized that he was right, so I did. 

What prompted your interest in modeling the coastal effects of hurricanes? 

I was a sophomore in 2005 when Hurricanes Katrina and Rita hit the Gulf Coast. The university is in northern Louisiana and we didn’t deal with the storm surges, but I remember the rain. And a lot of students were from places along the Gulf Coast. That allowed me to see the personal impacts of hurricanes. One of the band members was from New Orleans and his sister was killed in a shelter. I realized that it was people who looked like me on the news, sitting on roofs, and seemingly not being taken care of. Seeing that societal impact, particularly for my community, sparked my interest in trying to do something about it. 

The following summer I got an internship at the National Center for Atmospheric Research. I worked on a project to try to understand the relationship between the intensity of storms and atmospheric water vapor. I realized how much I loved research and doing something beyond analytical math that had a practical application. 

You went on to become the first African-American PhD student at what is now known as the Oden Institute for Computational Engineering and Sciences at the University of Texas. What was that experience like? 

The transition was very difficult. Initially, I felt isolated within the institute as the only Black person. You may not even be conscious of it, but if there is no one that looks like you who is studying or teaching in a program, it’s like a silent message. I had to get up to speed in computational math, there was this big learning curve, and I also was dealing with culture shock. I couldn’t relate to people on a personal level and I was intimidated, thinking everyone else was so far ahead of me. It took me a while to get myself together and adjust. 

UT Austin is mid-way between Dallas and Houston and near Louisiana, so it was relatively easy for me to connect with people that I knew, which was healthy for me. And once I got into my research things got much better. I loved working with mathematical models and computer coding. I had a really great advisor. The day I defended my dissertation went as smoothly as it could have gone. The timing, the way I answered questions, the way the sun looked when I walked out of the building. That was a perfect day. 

The net was positive. My initial struggles in graduate school make me a better mentor now. 

How do you sum up your research? 

I use a computer to solve math problems surrounding the way that fluid flows during storms. I work with a model that doesn’t have to depend on historical data from storms in coastal communities. I can change a variable in the model and determine how that may affect a storm’s impact. One of the scenarios that I look at a lot is variables due to climate change. 

I don’t study the atmosphere. I study the response of the ocean to the atmosphere. Many people get focused on the category of a hurricane, which tells you the wind strength. But there is also the hazard from water, via storm surge and inland flooding. The water hazards also pose a great threat to the built environment. And human deaths from hurricanes are usually related to water. 

What improvements would you like to see in national hurricane research?  

The hazards are multi-dimensional so we should not study the problems underlying them in isolation. Katrina was catastrophic not just became of the storm but because New Orleans is below sea level, it’s densely populated, and there was a failure of infrastructure. And there are bigger questions than those surrounding physical infrastructure. How do we develop the social infrastructure needed so that low-income people can evacuate in an emergency? How do we foster resilience? 

We need more science in politics if we want to protect coastlines. We need truly inter-disciplinary teams tackling the problems funded over 20-year timescales, so we don’t just do things halfway. As a nation, we’re so reactionary. But only one dollar in prevention equals six dollars spent on a reaction. 

Why did you decide to come to Emory? 

The faculty here really care about teaching and so do I. The students are well-supported, especially in the Department of Mathematics. And I feel valued as a truly inter-disciplinary researcher. I don’t belong in a box. Emory offers a lot of opportunity to grow as my interests evolve. I can collaborate with faculty from the Department of Environmental Sciences, the Department of Computer Science, the Rollins School of Public Health and elsewhere across campus. 

What do you hope will be your academic legacy? 

I want to make an impact scientifically. I want to write good papers and to advance knowledge. And, at the end of the day, I hope that people will say, “She was kind. She treated people well while she achieved those things.”

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New lead screening index zooms in on highest-risk areas in Georgia

Click here to see an interactive version of the map of priority screening index scores for low-level lead exposure in Georgia. Emory researchers, in partnership with health officials, are offering free soil testing of lead levels for Georgia residents through November 15. Click here for details.

By Carol Clark

While many people think of lead poisoning as a problem of the past, chronic exposure still occurs in some communities that may be missed in limited screening programs for children’s blood lead levels. Now researchers at Emory University have developed a more precise screening index, illustrated with a map, which provides a fine-grain view of areas where children are most at risk for low-level lead exposure in the city of Atlanta and throughout the state of Georgia. 

Scientific Reports published their new method, including analyses that tested and showed its efficacy, using historical data. 

The new screening index is based on established risk factors for lead exposure, including poverty and housing built before 1950. The index pinpointed 18 highest-priority census tracts in metro Atlanta, encompassing 2,715 children under the age of six — or 1.7 percent of all children that age in greater Atlanta. 

These highest-priority areas include the historically black neighborhoods of English Avenue and Vine City, where Emory researchers had previously identified elevated levels of lead in the soil of some yards and vacant lots. 

“As we move forward into an age when acute lead poisoning is rare, we need better tools to monitor for chronic, long-term exposure to lead,” says Emory graduate Samantha Distler, first author of the paper. “We developed an interactive map that can be used by physicians and other health officials, and even by individuals who want to check their own children’s risk levels. You can easily zoom in to find an exact location, so there’s less guess work involved in assessing what is a high-risk area.” 

The method could be applied to any area in the United States, she adds. 

Distler led the work as an Emory undergraduate majoring in quantitative sciences on the neuroscience and behavioral biology track. She is now a graduate student of epidemiology at the University of Michigan School of Public Health. 

“Lead is a toxicant that is particularly dangerous to children and their developing brains,” Distler says. “Even low blood lead levels are associated with neurological deficits in children.” 

“One of the biggest problems concerning lead is that many people don’t know if their children are being exposed,” says Eri Saikawa, senior author of the study and associate professor in Emory’s Department of Environmental Sciences and Rollins School of Public Health. “Detecting lead exposure as early as possible is very important so preventative measures can be taken. The easiest way to do that is to screen the blood.” 

The Saikawa lab is offering free soil testing of lead levels for Georgia residents through November 15, in partnership with the Georgia Department of Health, the Agency for Toxic Substances and Disease Registry and Georgia Adopt-A-Stream. Click here for details of how to collect a sample and where to drop it off. 

In 2018, the Saikawa lab collaborated with members of Atlanta’s Historic Westside Gardens to test urban soil on Atlanta’s Westside for contaminants. That project uncovered high levels of heavy metal and metalloids in some yards, and even some industrial waste known as slag. The project led to an investigation by the U.S. Environmental Protection Agency, which in 2019 began decontaminating properties in the area by removing and replacing soil. 

In addition to neurological deficits, lead exposure is associated with immunological and endocrine effects and cardiovascular disease. Decades ago, federal regulations reduced lead in paint and gasoline and other common exposure sources. The resulting drop in children’s blood lead levels in the United States is considered one of the greatest public health achievements in the country’s history. 

Many people remain unaware, however, that lead persists in the environment. “It can linger for a really long time in everything from soil to water,” Distler says. “That puts some people at risk for chronic exposures to low levels over a long time.” 

The Centers for Disease Control and Prevention (CDC) estimates that at least four million households in the United States have children living in them who are being exposed to high levels of lead. And about half a million of those children aged one to five years have blood lead levels above five micrograms per deciliter, the level at which the CDC recommends initiating public health action. 

Despite this alarming statistic, many children in higher-risk areas are not screened for blood lead levels. In Georgia, data from the period 2011 to 2018 show that the proportion in various ZIP code tabulation areas who have been tested range from 1 percent to 67 percent, with a median of 13 percent. 

The Emory researchers realized that one problem may be that health officials focus screening efforts on a county-wide basis, rather than zeroing in on the highest-risk neighborhoods within those counties. 

In 2009, a team led by researchers at the CDC developed and published a priority screen index for Atlanta neighborhoods based on housing age and percentage of residents enrolled in Georgia’s Special Supplemental Nutrition Program for Women, Infants and Children (WIC), a proxy for poverty. 

For the current paper, the Emory researchers built on the efforts of the 2009 paper, drilling down from neighborhoods to more precise U.S. Census Bureau tracts. Data from the American Community Survey was used to assess the relative level of poverty and proportion of homes built before 1950. 

A priority screening index, ranging from two to eight, was applied to the census tracts. The areas of highest relative poverty and proportion of homes built before 1950 received the highest score. The researchers applied this index to census tracts across the state of Georgia and to the entire United States to identify tracts that consistently have the highest priority screening index values. 

“The visualizations of our priority screening index that we’ve created using interactive maps can empower physicians and health officials to better target children at high risk for lead exposure,” Distler says. “We hope our work will help lead to improved policies and actions to reach children who are most at risk for lead exposure and to improve their lives — not just in Georgia but throughout the United States.”

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Leading a new era in ancient DNA research

A new ancient DNA lab at Emory is mapping little-explored human lineages, studying genetics of the deep past to better understand modern-day populations of the Americas.

Emory junior Rosseirys "Ro" De La Rosa is helping analyze DNA that she extracted from ancient bones unearthed in Uruguay — the remains of an Indigenous people known as the Charrúa. “Very few remains of the Charrúa have been found,” De La Rosa says. “They were largely wiped out by colonialism and a lot of mystery surrounds them. Anything that we can learn is important.”

It may be possible to connect the ancient Charrúa to modern-day populations unaware of their link. “Culture matters,” says De La Rosa, who is continuing to work on the project remotely this semester. “Leaning about your own culture gives you a sense of unity and connection that you can pass down to others.”

De La Rosa is a member of the Lindo Ancient DNA Laboratory, headed by John Lindo, Emory assistant professor of anthropology. The state-of-the-art facility, funded by major grants from National Geographic Explorer and the National Science Foundation, opened in January in Emory's Psychology and Interdisciplinary Sciences Building. It is one of the few in the world involved in every step of the complex process of solving mysteries surrounding ancient remains. 

"We build projects from the ground up," Lindo says. "We extract DNA from ancient remains here, sequence it here, analyze it here, and publish the results."

Most previous ancient DNA work involves people of European ancestry. A focus of the Emory lab, however is exploring how environmental changes — including those caused by European contact — affected the biology of Indigenous and other populations of the Americas.

"Our work can connect people to ancestries they potentially don't know about," Lindo explains. "It can also give them insights into how historic, and even prehistoric, events may be affecting them today, especially in terms of health risks and disparities."

Read the full story.

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Gender parity review of psychological science shows progress and problems

Emory psychologists Sherryl Goodman and Stella Lourenco were among the 59 researchers, from nearly 40 different institutions, who co-authored a review of gender parity in psychological science.

 
By Carol Clark

When Sherryl Goodman joined Emory’s Department of Psychology in 1977, she was the sole female member of the faculty. “I was typically the only woman in the room,” recalls Goodman, now Samuel Candler Dobbs Professor Psychology. 

Things have changed over the decades, both nationally and at Emory — where the percentage of women faculty in the Department of Psychology is approaching half. Despite the great gains in numbers of women in the profession, much more work is needed to achieve true gender parity, Goodman says. 

Goodman and Stella Lourenco, Emory associate professor of psychology, are among the authors of a report on gender parity in psychological science, based on an extensive review of peer-reviewed studies. Perspectives on Psychological Science published the review, entitled “The Future of Women in Psychological Science,” co-authored by 59 researchers from nearly 40 different institutions from across the United States, Canada and Australia. 

The authors found that women are attracted to psychology in record numbers and earn more doctoral degrees in the field than men. And women who choose to enter the academy as assistant professors of psychology are even more likely than men to get hired and are as likely as men to obtain tenure. They also found, however, that women are less likely to apply for tenure-track positions. And fewer women attain the rank of full professor than men. 

Women also remain underrepresented in more senior ranks in psychology departments and they are less likely to receive salaries comparable to those of men in these senior positions. And women across their careers are less likely to submit, renew and hold grants or to have publication and citation rates comparable to their male colleagues. 

“When I was a graduate student, my adviser used to tell me about the gender discrimination she faced as a woman in science and how I had it so much better,” recalls Lourenco, who joined the Emory faculty just over 10 years ago. “She was right. There has been much progress in the field. At the same time, there is still much more to do.” 

Some well-intentioned policies may have even backfired for women, Lourenco notes. For instance, parental leave is now available for both female and male faculty. “There is evidence that men may benefit more from parental leave than women, with relatively more publications than their counterparts at institutions without parental leave,” she says. “To be sure, parental leave is a good thing. But if women take on more of the burden of childcare, they will publish less than men on parental leave. Institutions need to be aware of such issues when later evaluating women for tenure and promotion.” 

The review cites a 2016 survey in which U.S. mothers reported spending 75 percent more hours per week on childcare than fathers did. 

Academic careers are still not seen as “woman friendly,” Goodman notes. “We still lose a number of talented Ph.D. graduates who don’t even bother applying because they don’t see viable careers in academics for women. That’s sad and a loss to the field of psychological science, and to the academy more broadly,” she says. 

Among the recommendations that the review urges universities to consider are: Offer high-quality, affordable childcare; supplement the cost of egg freezing to expand women’s fertility windows; and provide support through more partner hires or benefits packages that include employment for a spouse outside the university. 

The authors also called for enabling women to improve salary negotiation skills and for greater transparency related to compensation. They cite a 2018 National Science Foundation report that found, across all institutions, women’s full professor salaries were 88 percent that of men, and their associate professor salaries were 92 percent that of men. 

The review focused on women in general in psychological science, while noting that women of color and people who are a minority in terms of gender orientation face extra challenges that also need to be addressed. 

Although the review did not include the impact of COVID-19, the pandemic highlights the problem of gender disparity more broadly, Goodman says. 

“Women tend to share more of the burden of taking care of a family, and suddenly, many of them also had to become teachers of their children,” she says. “The pandemic compounds the impact of an already existing problem. It may be another factor that causes some women to have to opt out of the workforce or to become less productive in their jobs.” 

The review authors sum up their findings in a concluding statement: “The need to address the issues facing women in psychological science coincides with a particular cultural moment in U.S. and global social history, one in which women are speaking out and taking action in an unprecedented way to address sexual harassment, financial and social inequality and gender biases. As a field committed to the science of equality, psychology has the opportunity to lead other disciplines in how best to create and maintain a culture of inclusion.”

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'Firefly' method makes cellular forces visible at molecular scale

The image on the left shows the force activity of a cell at a resolution of about 250 nanometers. The image on the right shows how much clearer the image becomes with the resolution of 25 nanometers that is now possible with the new technique. (Microscopy photos by Alisina Bazrafshan)

Scientists have developed a new technique using tools made of luminescent DNA, lit up like fireflies, to visualize the mechanical forces of cells at the molecular level. Nature Methods published the work, led by chemists at Emory University, who demonstrated their technique on human blood platelets in laboratory experiments.

"Normally, an optical microscope cannot produce images that resolve objects smaller than the length of a light wave, which is about 500 nanometers," says Khalid Salaita, Emory professor of chemistry and senior author of the study. "We found a way to leverage recent advances in optical imaging along with our molecular DNA sensors to capture forces at 25 nanometers. That resolution is akin to being on the moon and seeing the ripples caused by raindrops hitting the surface of a lake on Earth."

Almost every biological process involves a mechanical component, from cell division to blood clotting to an immune response. "Understanding how cells apply forces and sense forces may help in the development of new therapies for many different disorders," says Salaita, whose lab is a leader in devising ways to image and map bio-mechanical forces.

The first authors of the paper, Joshua Brockman and Hanquan Su, did the work as Emory graduate students in the lab. Both recently received their PhDs.

Read the full story here.

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Experiments reveal why human-like robots elicit uncanny feelings

"At the core of this research is what we perceive when we look at a face," says Emory psychologist Philippe Rochat, senior author of the study. (Getty Images)

By Carol Clark

Androids, or robots with humanlike features, are often more appealing to people than those that resemble machines — but only up to a certain point. Many people experience an uneasy feeling in response to robots that are nearly lifelike, and yet somehow not quite “right.” The feeling of affinity can plunge into one of repulsion as a robot’s human likeness increases, a zone known as “the uncanny valley.”

The journal Perception published new insights by Emory psychologists into the cognitive mechanisms underlying this phenomenon.  

 

Since the uncanny valley was first described, a common hypothesis developed to explain it. Known as the mind-perception theory, it proposes that when people see a robot with human-like features, they automatically add a mind to it. A growing sense that a machine appears to have a mind leads to the creepy feeling, according to this theory.

 

“We found that the opposite is true,” says Wang Shensheng, first author of the new study, who did the work as a graduate student at Emory and recently received his PhD in psychology. “It’s not the first step of attributing a mind to an android but the next step of ‘dehumanizing’ it by subtracting the idea of it having a mind that leads to the uncanny valley. Instead of just a one-shot process, it’s a dynamic one.”

 

The findings have implications for both the design of robots and for understanding how we perceive one another as humans.

 

“Robots are increasingly entering the social domain for everything from education to healthcare,” Wang says. “How we perceive them and relate to them is important both from the standpoint of engineers and psychologists.”

 

“At the core of this research is the question of what we perceive when we look at a face,” adds Philippe Rochat, Emory professor of psychology and senior author of the study. “It’s probably one of the most important questions in psychology. The ability to perceive the minds of others is the foundation of human relationships. ”

 

The research may help in unraveling the mechanisms involved in mind-blindness — the inability to distinguish between humans and machines — such as in cases of extreme autism or some psychotic disorders, Rochat says.

 

Co-authors of the study include Yuk Fai Cheong and Daniel Dilks, both associate professors of psychology at Emory.

 

Anthropomorphizing, or projecting human qualities onto objects, is common. “We often see faces in a cloud for instance,” Wang says. “We also sometimes anthropomorphize machines that we’re trying to understand, like our cars or a computer.”

 

Naming one’s car or imagining that a cloud is an animated being, however, is not normally associated with an uncanny feeling, Wang notes. That led him to hypothesize that something other than just anthropomorphizing may occur when viewing an android.

 

To tease apart the potential roles of mind-perception and dehumanization in the uncanny valley phenomenon the researchers conducted experiments focused on the temporal dynamics of the process. Participants were shown three types of images — human faces, mechanical-looking robot faces and android faces that closely resembled humans — and asked to rate each for perceived animacy or “aliveness.” The exposure times of the images were systematically manipulated, within milliseconds, as the participants rated their animacy.

 

The results showed that perceived animacy decreased significantly as a function of exposure time for android faces but not for mechanical-looking robot or human faces. And in android faces, the perceived animacy drops at between 100 and 500 milliseconds of viewing time. That timing is consistent with previous research showing that people begin to distinguish between human and artificial faces around 400 milliseconds after stimulus onset.

 

A second set of experiments manipulated both the exposure time and the amount of detail in the images, ranging from a minimal sketch of the features to a fully blurred image. The results showed that removing details from the images of the android faces decreased the perceived animacy along with the perceived uncanniness.

 

“The whole process is complicated but it happens within the blink of an eye,” Wang says. “Our results suggest that at first sight we anthropomorphize an android, but within milliseconds we detect deviations and dehumanize it. And that drop in perceived animacy likely contributes to the uncanny feeling.”

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Study shows how a single gene drives aggression in wild songbirds

White-throated sparrows come in two different morphs, the white-striped (left) and the tan-striped (right). The morphs have both different plumage and behaviors, making these wild songbirds a good model organism for the genetic basis of behavior. (Photo by Jennifer Merritt)

By Carol Clark

A new study shows how differentiation of a single gene changes behavior in a wild songbird, determining whether the white-throated sparrow displays more, or less, aggression. The Proceedings of the National Academy of Sciences (PNAS) published the research, led by neuroscientists at Emory University.

The researchers singled out an estrogen receptor from a complex of more than 1,000 genes known as a “supergene,” or genetic material inherited together as a block. The work provides a rare look at how genomic divergence can lead to behavioral divergence in a vertebrate.

“Evolution has tinkered with the DNA sequence of a gene of this songbird, and we demonstrated that those little changes affect both the expression of the gene and the bird’s behavior,” says Emory graduate student Jennifer Merritt, first author of the paper.

Merritt is a PhD candidate in the lab of Donna Maney, senior author of the paper and an Emory professor of psychology.

“White-throated sparrows are common backyard birds found through most of North America,” Merritt says. “What’s remarkable about them is that they occur in two different morphs that have not only different plumage, but also different strategies for maximizing reproductive output. Both types of differences are caused by genetic differentiation of only one region of a single chromosome, and we know exactly where it is.”

At some point during the evolution of a species, a chromosome can break and flip. This process, called an inversion, isolates the genes that are trapped inside, producing a supergene. In some cases, supergenes have led to distinct morphs within a single species — individuals with the supergene and those without it.

In the case of the white-throated sparrows, the white-striped morph sports bright yellow, black and white stripes on its crown while the tan-striped morph has more muted, tan and grayish stripes. The white-striped birds, which all possess at least one copy of the rearranged chromosome, tend to be more aggressive and less parental than the tan-striped birds, which do not have the rearranged chromosome.

“Scientists have hypothesized for 100 years that inversions are important for the evolution of some of the complex behaviors that we see in nature,” Maney says. “But inversions are challenging to understand because, when they turn into supergenes, all of the genes are inherited together. We already knew a lot about the natural history of the white-throated sparrow, as well as the biological mechanisms underlying its aggression. Using that knowledge, we were able to finally show the evolutionary role of a supergene at the molecular level.”

The current paper builds on previous work by the Maney lab, a leader in connecting gene sequence with behavior in free-living animals. In 2014, the lab identified a hormone receptor —estrogen receptor alpha (ER-alpha) — that appeared connected to the differences in the sparrows’ aggression and parenting behaviors in the wild. The white-striped birds express this receptor at much higher levels than the tan-striped birds, and the more the expression, the more aggressive the bird.

“For this paper, we wanted to follow the genetic variation of ER-alpha all the way up to where it’s expressed in the brain, and then to behavior, to see if we could trace the behavioral variation to variation in this one gene,” Merritt says.

The birds sing to establish a territory. The rate at which they sing gives a measure of their level of aggression, along with the frequency at which they charge, or “attack,” animals encroaching on what they consider their territory.

In field studies of white-throated sparrows in their natural habitat, the researchers showed that the more a bird expresses the supergene version of the estrogen receptor, the more vigorously it defends its territory.

The researchers then moved beyond the correlational work by taking an experimental approach. White-throated sparrows in the lab were given a substance to block expression of the ER-alpha gene and their aggression levels were measured. The results showed that when expression of that one gene was blocked, the aggression of the white-striped birds went down so they behaved like the tan-striped ones.

“We believe this is the first demonstration of how a single gene within a supergene drives changes in a social behavior in a wild vertebrate,” Merritt says. She gives an analogy for the challenge involved: “Imagine each of the genes within a supergene as tributaries converging into a river, the behavior. And then taking a sample of water from the river and determining which tributary the sample came from.”

The Maney lab is continuing to investigate a suite of other neuroendocrine genes captured by the chromosome rearrangement in the white-throated sparrow that are thought to be important players in the regulation of social behavior.

Co-authors of the PNAS paper include Eric Ortlund, a biochemist and an expert in the ER-alpha gene at the Emory School of Medicine; Kathleen Grogan and Wendy Zinzow-Kramer, former post-doctoral fellows in the Maney lab; and Dan Sun and Soojin Yi, from Georgia Tech. The work was funded by grants from the National Institutes of Health and the National Science Foundation.

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Emory students win Amazon's Alexa Prize for AI with strategy of caring about others

Jinho Choi (center), the faculty advisor for the Emory Alexa Prize team, with graduate students James Finch (left), and Sarah Fillwock, the team leader.

A team of Emory University students won Amazon’s 2020 Alexa Prize, a global competition to create the most engaging chatbot to advance the field of artificial intelligence. The team earned $500,000 for taking first place with their chatbot named Emora.

The students designed Emora to provide comfort and warmth to people interacting with Amazon’s voice-activated Alexa-enabled devices, whether they wanted to discuss movies, sports and their pets or their concerns for themselves and their families amid the COVID-19 pandemic.

The Emory team consisted of 14 students led by graduate student Sarah Fillwock and faculty advisor Jinho Choi, assistant professor in the Department of Computer Science. They christened their chatbot Emora because it sounds like a feminine version of “Emory” and is similar to a Hebrew term for a sage skilled in eloquence.

Even as they celebrate their win, the Emory team is looking ahead to how they can apply the concepts they developed to benefit everything from education to people suffering from depression and social isolation.

The annual Alexa Prize, launched in 2016, challenges university students to make breakthroughs in the design of chatbots, or social bots — software apps that simplify interactions between humans and computers by allowing them to talk with one another. Emory used a unique strategy to beat out nine other universities and take the top spot in this year’s competition, the most hotly contested ever. 

“Normally people think of a chatbot as being an intelligent assistant, to answer questions or provide a customer service,” Fillwock says. “We designed a more socially oriented chatbot that could actually show interest in an individual user and provide comfort to people if they wanted it.”

Read the full story.

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Butterfly genomics: Monarchs fly differently, but meet up and mate

An eastern monarch butterfly rests in Saint Marks, Florida, on its way to overwinter in Mexico. (Photo by Venkat Talla)

Each year, millions of monarch butterflies migrate across eastern North America to fly from as far north as the U.S.-Canadian border to overwinter in central Mexico — covering as much as 3,000 miles. Meanwhile, on the other side of the Rocky Mountains, western monarchs generally fly 300 miles down to the Pacific Coast to spend the winter in California. It was long believed that the eastern and western monarchs were genetically distinct populations.

A new study, however, confirms that while the eastern and western butterflies fly differently, they are genetically the same. The journal Molecular Ecology published the findings, led by evolutionary biologists at Emory University.

“It was surprising,” says Jaap de Roode, Emory professor of biology and senior author of the study. His lab is one of a handful in the world that studies monarch butterflies.

“You would expect that organisms with different behaviors and ecologies would show some genetic differences,” de Roode says. “But we found that you cannot distinguish genetically between the western and eastern butterflies.”

Read the whole story here.

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Beautyberry leaf extract restores drug's power to fight 'superbug'

"We decided to investigate the chemical properties of the American beautyberry because it was an important medicinal plant for Native Americans," says Emory ethnobotanist Cassandra Quave, a senior author of the study. (Photo by Tharanga Samarakoon)

By Carol Clark

Scientists discovered a compound in the leaves of a common shrub, the American beautyberry, that boosts an antibiotic’s activity against antibiotic-resistant staph bacteria. Laboratory experiments showed that the plant compound works in combination with oxacillin to knock down the resistance to the drug of methicillin-resistant Staphylococcus aureus, or MRSA.

The American Chemical Society's ACS Infectious Diseases published the finding, led by scientists at Emory University and the University of Notre Dame.

The American beautyberry, or Callicarpa americana, is native to the southern United States. Prolific in the wild, the shrub is also popular in ornamental landscaping. It’s known for showy clusters of bright purple berries that begin to ripen in the summer and are an important food source for many species of birds.

“We decided to investigate the chemical properties of the American beautyberry because it was an important medicinal plant for Native Americans,” says Cassandra Quave, co-senior author of the study and an assistant professor in Emory University’s Center for the Study of Human Health and Emory School of Medicine’s Department of Dermatology. Quave is also a member of the Emory Antibiotic Resistance Center and a leader in the field of medical ethnobotany, studying how indigenous people incorporate plants in healing practices to uncover promising candidates for new drugs.

Micah Dettweiler, a recent Emory graduate and a staff member of the Quave lab, is first author of the study. Christian Melander, professor of chemistry at Notre Dame, is co-senior author.

The Alabama, Choctaw, Creek, Koasati, Seminole and other Native American tribes relied on the American beautyberry for various medicinal purposes. Leaves and other parts of the plant were boiled for use in sweat baths to treat malarial fevers and rheumatism. The boiled roots were made into treatments for dizziness, stomachaches and urine retention, while bark from the stems and roots were made into concoctions for itchy skin.

Previous research found that extracts from the leaves of the beautyberry deter mosquitoes and ticks. And a prior study by Quave and colleagues found that extracts from the leaves inhibit growth of the bacterium that causes acne. For this study, the researchers focused on testing extracts collected from the leaves for efficacy against MRSA.

“Even a single plant tissue can contain hundreds of unique molecules,” Quave says. “It’s a painstaking process to chemically separate them out, then test and retest until you find one that’s effective.”

The researchers identified a compound from the leaves that slightly inhibited the growth of MRSA. The compound belongs to a group of chemicals known as clerodane diterpenoids, some of which are used by plants to repel predators.

Since the compound only modestly inhibited MRSA, the researchers tried it in combination with beta-lactam antibiotics.

“Beta-lactam antibiotics are some of the safest and least toxic that are currently available in the antibiotic arsenal,” Quave says. “Unfortunately, MRSA has developed resistance to them.” 

Laboratory tests showed that the beautyberry leaf compound synergizes with the beta-lactam antibiotic oxacillin to knock down MRSA’s resistance to the drug.

The next step is to test the combination of the beautyberry leaf extract and oxacillin as a therapy in animal models. If those results prove effective against MRSA infections, the researchers will synthesize the plant compound in the lab and tweak its chemical structure to try to further enhance its efficacy as a combination therapy with oxacillin.

“We need to keep filling the drug-discovery pipeline with innovative solutions, including potential combination therapies, to address the ongoing and growing problem of antibiotic resistance,” Quave says.

Each year in the U.S., at least 2.8 million people get an antibiotic-resistant infection and more than 35,000 people die, according to the Centers for Disease Control and Prevention.

“Even in the midst of the COVID-19, we can’t forget about the issue of antibiotic resistance,” Quave says. She notes that many COVID-19 patients are receiving antibiotics to deal with secondary infections brought on by their weakened conditions, raising concerns about a later surge in antibiotic-resistant infections.

Co-authors of the study include Emory post-doctoral fellow Gina Porras; Emory graduate students Caitlin Risener and Lewis Marquez; Tharanga Samarakoon, collections manager of the Emory Herbarium; and Roberta Melander from the University of Notre Dame.

The work was supported by the National Institute of Allergy and Infectious Disease, the National Institute of General Medical Sciences, the Jones Ecological Research Center and Emory University.

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Georgia Coast Atlas: A portal to hidden stories

The rich biodiversity of the Georgia coast includes the roseate spoonbill, shown in a marsh on Sapelo Island. Photo by Anthony Martin.

The Georgia Coast Atlas is a public, online gateway to the dynamic ecosystems and intriguing history of the state’s 100-mile-long coast and barrier islands. Emory University’s Department of Environmental Sciences and the Emory Center for Digital Scholarship launched the ambitious project. It showcases scholarship in science and the humanities, weaving together research, fieldwork and technology to create an unprecedented resource for educators, conservationists, students and the general public.

The interactive trove — made up of stunning flyover video, oral and written stories and annotated maps — keeps expanding through the efforts of Emory students and faculty.

“The main aim of the Atlas is to show how special the Georgia coast is as a place,” says Anthony Martin, a professor of practice in Environmental Sciences. “Secondly, it documents how the region is rapidly changing.”

Read the whole story here.

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