Bringing to life 'Dinosaurs Without Bones'

Tony Martin investigates an outcrop in Australia. Photo by Ruth Schowalter.

Emory ichnologist Anthony Martin wants to shake up your view of dinosaurs by letting you follow them in their tracks. (Warning: Watch where you step.)

Martin is on a mission to bring ichnology to the masses. Long overshadowed by the bone specialists of paleontology, paleoichnologists focus on the fossils of tracks, nests, burrows, dung and other traces of life.

Martin’s new book, “Dinosaurs Without Bones: Dinosaur Lives Revealed by Their Trace Fossils” is published by Pegasus Books. In a review, Publisher’s Weekly says Martin’s writing “bubbles over with the joy of scientific discovery as he shares his natural enthusiasm for the blend of sleuthing and imagination that he brings to the field of ichnology.”

Martin also drew all of the illustrations for the book, and took most of the photos.

eScienceCommons interviewed the author in his office in Emory’s Department of Environmental Sciences.

eScienceCommons: Your previous five books have been geared more towards academics. Why did you decide to write this one for a general audience? 

Tony Martin: One of my goals is to help turn the term “ichnology” into a household word. And I want to help people see dinosaurs in a new way: Not just as skeletons in a museum, but with muscles and flesh, moving and making traces.

eSC: What sort of readers do you think will enjoy this book?

TM: Anyone who loves dinosaurs. But also people who love detective stories, which often involve the scientific method. Sherlock Holmes, who was a nerd long before it was hip, is making a comeback as a TV series. A lot of people enjoy watching him solve problems by making careful observations, and then forming hypotheses on the basis of those observations.

I’m writing about mysteries that, in some cases, go back more than 100 million years. Dinosaurs left behind many observable clues about what they did while they were alive.

You see a deserted plain. Here's what an ichnologist sees. Drawing by Tony Martin.

eSC: You open the book with a thrilling scene, of two big, male Triceratops charging across a floodplain, creating havoc among a group of feathered theropods and a flock of toothed birds and pterosaurs. It’s a bit like Jurassic Park without the humans. 

TM: Almost everything that happens in that opening scenario is based on real evidence. It’s creative non-fiction, describing behaviors as they may have happened, based on trace-fossil records. There is a lot of action in the book. It’s not just a mystery – it’s also a thriller.

eSC: I love it that one of your favorite trace fossils is of a dinosaur butt. 

TM: It is rare to see a dinosaur-resting trace. One of the best examples is from a small theropod, discovered in Utah. It’s intriguing to me to think of a dinosaur sitting down and leaving an impression. Why did it sit down? To digest a big meal? To survey a scene? Dinosaurs don’t always have to be running, eating machines.

eSC: You also write about dinosaurs belching, breaking wind, peeing, pooping and even puking. You seem almost shameless in your quest to appeal to the masses. 

TM: If there is anything that will get me on The Colbert Report, it’s my diagram of a Brachiosaurus projectile vomiting (see above), including the estimated impact velocity of the stream and the associated crater. I checked with (Emory physicist) Jed Brody to make sure I got the physics right. It’s a fantasy trace fossil – no one has found an undoubted trace fossil of dinosaur vomit yet – but that doesn’t mean they aren’t out there.

eSC: And, of course, you have included dinosaur violence and sex. 

TM: Trace fossils of fighting can tell you a lot about dinosaur behavior. For instance, we have evidence of a Tyrannosaurus taking a chunk out of the tail of an Edmontosaurus, which survived the damage. The trace fossil marks of the teeth row on the skeleton are more than a foot across, which narrows down the list of perpetrators to a tyrannosaur closely related to Tyrannosaurus rex, or T. rex itself.

Part of my inspiration for writing about dinosaur sex comes from a section in the book “My Beloved Brontosaurus,” by Brian Switek. He described the spikes on the tails of stegosaurs, and pondered how the males might have gotten past those.

I thought I’d take that idea a step further and imagine what kind of trace fossils dinosaurs might have made while mating.

"A cassowary really looks like something out of Jurassic Park," says Martin. Photo by Paul IJsendoorn/Wikipedia Commons. 

eSC: Your book chapters have some dynamite opening sentences. One of my favorites is, “The large theropod tracks were fresh, and so was its scat.” 

TM: We can observe dinosaur behavior by studying and tracking the traces of birds, which are living theropods. Those particular tracks were from a cassowary encounter I had during a field trip with Emory students in Queensland, Australia.

The sunlight was coming across this giant bird as it was crossing a stream. It was an amazing sight. Cassowaries can grow to more than six-feet tall. They’re among the tallest, heaviest birds alive. They are covered with black feathers, and their head is topped with a tall, bladed crest that looks as if it can saw through flesh. A cassowary really looks like something out of Jurassic Park.

eSC: How long did it take you to write this book? 

TM: In terms of experience, the book took 30 years of work in ichnology and geology. It took a while for me to develop the right combination of field experience, knowledge and writing ability to put it all together into something a reader would enjoy.

The actual writing of the book took just a little more than a year. It really flowed out of me. It was fun to write because I got to blend my scientific expertise with pop culture and other human-interest topics to tell a story that uses ichnology as a central theme.

Here in the United States we like to bemoan how we have a scientifically illiterate public, but people are interested in good science stories. I would encourage more scientists to think about writing in ways that are approachable to general audiences.

eSC: Who are your favorite science writers who appeal to general audiences?

TM: There are so many good science writers now. To name just a few that I enjoy: David Quammen, Virginia Hughes, Ed Yong, Brian Switek, Carl Zimmer, Virginia Morell and Annalee Newitz.

Related:
Dinosaur burrows yield clues to climate change
Polar dinosaur tracks open new trail to past
Lake-bed trails tell ancient fish story 
Tell-tale toes point to fossilized bird tracks

Asian elephants reassure others in distress

Elephants get distressed when they see others in distress, reaching out to calm them down.  Photos, above and below, by Elise Gilchrist, Think Elephants International.

By Carol Clark

Asian elephants console others who are in distress, using physical touches and vocalizations, finds a study to be published in the journal PeerJ.

The findings are the first empirical evidence of consolation in elephants, says lead author Joshua Plotnik, who began the research as a graduate student of psychology at Emory University. “For centuries, people have observed that elephants seem to be highly intelligent and empathic animals, but as scientists we need to actually test it,” he says.

Consolation behavior is rare in the animal kingdom, with empirical evidence previously provided only for the great apes, canines and certain corvids.

“With their strong social bonds, it’s not surprising that elephants show concern for others,” says co-author Frans de Waal, an Emory professor of psychology and director of Living Links at Emory’s Yerkes National Primate Research Center. “This study demonstrates that elephants get distressed when they see others in distress, reaching out to calm them down, not unlike the way chimpanzees or humans embrace someone who is upset.”

In the above video, a female elephant hears another make a distress call. She runs toward her upset companion, making soothing, chirping vocalizations and physical contact. Video by Joshua Plotnik.

Plotnik received his PhD from Emory in 2010 and is currently a lecturer in conservation biology at Mahidol University in Thailand and CEO of Think Elephants International, a non-profit focused on education and conservation. His main research interest is convergent cognitive evolution: The independent evolution of similar features of intelligence in species of different lineages.

While Plotnik was still at Emory, he and de Waal provided evidence that elephants can both recognize themselves in a mirror – a test of self-awareness passed only by some apes, dolphins and magpies – and problem-solve cooperatively.

“Humans are unique in many ways, but not in as many ways as we once thought,” Plotnik says.

The current study focused on a group of 26 captive Asian elephants spread over about 30 acres at an elephant camp in northern Thailand. For nearly a year, the researchers observed and recorded incidences when an elephant displayed a stress reaction, and the responses from other nearby elephants.

The initial stress responses came from either unobservable, or obvious, stimuli: Events such as a dog walking past, a snake or other potentially dangerous animal rustling the grass, or the presence of another, unfriendly elephant. “When an elephant gets spooked, its ears go out, its tail stands erect or curls out, and it may emit a low-frequency rumble, trumpet and roar to signal its distress,” Plotnik says.

 An elephant puts its trunk in another elephant's mouth: An elephant hug.

The study found that nearby elephants affiliated significantly more with a distressed individual through directed, physical contact following a stress event than during control periods. As a typical example, a nearby elephant would go to the side of the distressed animal and use its trunk to gently touch its face, or put its trunk in the other animal’s mouth.

The gesture of putting their trunks in each other’s mouths is almost like an elephant handshake or hug, Plotnik says. “It’s a very vulnerable position to put yourself in, because you could get bitten. It may be sending a signal of, ‘I’m here to help you, not hurt you.’”

The responding elephants also showed a tendency to vocalize. “The vocalization I heard most often following a distress event was a high, chirping sound,” Plotnik says. “I’ve never heard that vocalization when elephants are alone. It may be a signal like, ‘Shshhh, it’s okay,’ the sort of sounds a human adult might make to reassure a baby.”

In addition, elephants frequently responded to the distress signals of other elephants by adopting a similar body or emotional state, a phenomenon known as “emotional contagion,” which may be related to empathy. Groups of nearby elephants also were more likely to bunch together, or make physical contact with each other.

As an example of emotional contagion in humans, Plotnik describes a couple watching a movie: “When a character on the screen is scared, the hearts of the couple watching might race and they might move a bit closer and hold each others hands.”

"Humans are unique in many ways, but not in as many ways as we once thought," Plotnik says.

Decades ago, de Waal was one of the first to provide evidence of reconciliation in non-human primates, showing how chimpanzees make up with one another after a fight. De Waal’s research also demonstrated consolation behavior: After two chimpanzees fight, a third individual may come over and console the distressed loser of the battle with an embrace.

Reconciliation behaviors have since been demonstrated in many more species than those that have shown the capacity for consolation. “One hypothesis for why we don’t see consolation as often is that more complex cognition may underlie it,” Plotnik says. “Rather than just functioning as a way to maintain or repair relationships in a social group, consolation may also require empathy: The ability to put yourself emotionally into someone else’s shoes.”

The current elephant study’s limitations include the fact that it was restricted to captive animals. “This study is a first step,” Plotnik says. “I would like to see this consolation capacity demonstrated in wild populations as well.”

Wild populations of elephants, however, are becoming increasingly scarce: Both Asian elephants and African elephants are endangered. In addition to conducting research, Plotnik strives to educate children in Thailand and the United States about the importance of conserving elephants and their shrinking habitats.

“I really believe that to save elephants and other endangered species, we must educate children about them,” he says. “Part of our Think Elephants International curriculum is getting kids directly involved in the research we do, so they learn first-hand about these amazing animals. Elephants are incredibly majestic and there is still so much to learn about their behavior and intelligence.”

Related:
The elephant in the classroom
Hugs go way back in evolution

A sea lion that bops to a musical beat

Kate Lanau reported for Maclean’s on a panel at the American Association for the Advancement of Science, in Chicago, about how studies of animals may help us understand the evolution of our own musical capacity. Below is an excerpt:

“One of the biggest surprises has come from a California sea lion named Ronan, a species that doesn’t seem to be capable of complex vocal learning; although this sea lion can, it turns out, bop along to a beat.

"'We thought, let’s find an animal that’s not closely related to humans, and not vocally flexible,’ says Peter Cook, who was then at the University of California, Santa Cruz and is now at Emory University. ‘Sea lions are extremely charismatic and very adaptive,’ he continues; they also eat a lot, providing plenty of opportunities to train them with snacks. And while primates might push back against overly formal exercises, sea lions seem to thrive on it. ‘They’re kind of type A, I guess.’ Initially, Ronan wasn’t able to synchronize with a beat, but after months of training, she could transfer between a range of tempos. This is a key difference between Ronan’s behavior and what we might see in a circus animal, Cook says: those may be responding to visual cues, or performing a preordained dance routine. Ronan was responding directly to music. He says, ‘it was just her and the beat.’

Read the whole article on the Maclean’s web site.

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The art and science of causal illusions

Hadar Naftalovich studies how causal illusions form. The aim is to prevent these illusions from getting out of hand, "as can sometimes occur in people with paranoia, obsessive-compulsive disorder or depression," she says. Photo by Kay Hinton.

Emory senior Hadar Naftalovich is majoring in psychology and minoring in visual arts. She has combined both to conduct experiments in causal illusions for the Mind and Language Lab of Emory psychologist Phillip Wolf.  Naftalovich wrote about her research in the current issue of Emory Magazine:

Imagine that your friend asks you if you got the job you recently interviewed for. You respond that you hope so, and quickly knock on wood to prevent any bad luck that could arise from that statement. Do you truly believe that knocking on wood prevented the bad luck?

Causal illusions are situations in which a causal relationship is inferred when there is no possible mechanism to validate that relationship. In order to study the formation and characteristics of causal illusions, we needed to provide participants with situations analogous to real-life scenarios and measure their false cause-effect beliefs.

We created two sets of animations, one focusing on a tray filled with water and the other focusing on a watch on a chain. With these animations, we manipulated contact, direction, and motion to create situations where a causal relationship was clearly present (such as a hand hitting a tray with water and a ripple occurring on the same side that the hand made contact on) and ones where the causal relationship was false (such as the hand failing to hit the tray and a ripple still emerging, but from the opposite side from which the hand moved).

We predicted that causal illusions are formed when people infer forces, even when the forces are illegitimate. If our hypothesis is correct, the ratings of causation would be strongest when contact, movement, and direction matched and weakest with no movement. Also, if there were sufficient evidence for a causal connection (such as movement) but no mechanism to validate that connection (no contact) there will be a stronger rating of causation when direction matched. Our results supported our hypothesis for both sets of animations.

Through my research I hope to better understand the processes that allow causal illusions to form and find ways to apply that knowledge to preventing these illusions from getting out of hand, as can sometimes occur in people with paranoia, obsessive-compulsive disorder, or depression. My favorite part about doing this research is that I am able to use my art skills to advance my knowledge of psychology and use my pursuit of knowledge in psychology to advance my art skills.

You can read about more research projects of Emory undergraduates in Emory Magazine.

Creating an atmosphere for change

"It's really not possible to understand climate change from the standpoint of one discipline," says Eri Saikawa.

By Carol Clark

Most of the faculty in Emory’s Department of Environmental Sciences look forward to getting into the field, whether it’s to track wild primates through an African rainforest, chase after bumblebees in a Rocky Mountain meadow or just splash through metro-Atlanta streams to monitor mosquitoes and their larvae.

Eri Saikawa, however, loves nothing better than being indoors, battling computer-programming bugs as she wades into murky problems involving mathematics, atmospheric chemistry, and global environmental policy.

“I was never an outdoor person,” says Saikawa, assistant professor of environmental sciences. She smiles at the irony as she sits before her computer, wrapped in a comfy throw to ward off the fall chill seeping through the windows of her fifth-floor office. Using a numerical model, she is able to analyze the link between current emissions, air quality, and the climate to understand the impact of economic activities on the environment in different parts of the world.

Saikawa is an eclectic mix of interests, experience, and knowledge. Her research into public policy and the science of emissions linked to air pollution, ozone depletion, and global warming forms a patchwork quilt of expertise that covers many of the major environmental issues facing the world today.

Since she arrived at Emory last year, Saikawa and her colleagues have identified more than two dozen faculty and staff, from anthropology to sociology, from business to public health, whose work involves climate change. “We’re hoping to knit this network of faculty together into a team at Emory,” Saikawa says. She would eventually like to see this network expand to include researchers at Georgia Tech and other nearby institutions.

“It’s really not possible to understand climate change from the standpoint of one discipline,” she says. “Our energy system is changing. Our air is changing. Our supplies of water and energy are changing. The way we use land is changing. Ecosystems are changing. It’s not just climate change. It’s really global environmental change, and change in one system affects another, and so on. We need to find ways to show how it is all connected.”

Read the whole article in Emory Magazine.

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Putting people into the climate change picture

A close look at tourism's impact in rural China

Women in Upper Jidao village, Guizhou, wear their festival attire and perform Miao songs and dances for tourists. Photo by Jenny Chio.

By Carol Clark

While most of the world has been dazzled by the transformation of China’s cities in recent years, Emory anthropologist Jenny Chio has been quietly recording changes in the rural way of life. Her documentary film “农家乐 Peasant Family Happiness” explores the impact of tourism in China, from the perspective of residents of two rural villages where urbanites go to seek a “country” experience.

The film, which won the 2013 David Plath Media Prize from the Society for East Asian Anthropology, is getting good reviews as it makes the rounds of conferences and festivals. In May, Chio has a book coming out, “A Landscape of Travel: The Work of Tourism in Rural Ethnic China,” which will give more details about the impact of touristic desires on village life, while also delving into the visual politics of tourism and photography.

“I’m fascinated by tourism and I think it’s an important topic,” Chio says, “but I don’t study tourists. I made a decision early on to focus instead on the people who are actually doing the work to create an enjoyable, cultural experience for the tourists.”

Watch a BBC interview with Jenny Chio:


Chio was born in the United States, to parents who immigrated from Taiwan in the early 1970s. She was raised in the Midwest and California and speaks Mandarin Chinese.

As an undergraduate majoring in anthropology at Brown University she became interested in museums, particularly those run by Native Americans, and how they are used to address historical trauma and promote revitalization of cultural heritage.

After graduation, she spent a year teaching English in Beijing. “That’s when I realized that everything that I thought I knew about China was inadequate,” Chio says. “It was like, ‘Wow! I have so much to learn about this place.’”

The crowds of people, cars and non-stop construction can feel overwhelming to a first-time visitor to a city in China, she says. “Beijing is much louder than an American city. There is this energy that comes from the fact that life in China has changed so dramatically, so quickly. The buildings are so new and so shiny and modern.”

She cites a running joke: Reports of Chinese tourists going to Europe and the United States and being disappointed that the cities look so old and decrepit in comparison.

Chio went to Goldsmiths College, University of London, for a masters degree in visual anthropology. For her thesis, she created a digital video on the representation of ethnic minorities in Chinese ethnographic films from the 1950s and 1960s, titled “Film the People.”

In this still image from "Peasant Family Happiness" a village woman muses whether she should maintain an "ethnic" look while doing her household chores.

While “visual anthropology” is fairly new as a term and as a sub-discipline, “anthropologists have been using still photos and film cameras since their invention,” Chio says. “But many in the field have considered imagery as too slippery for communicating research because you can’t control how people interpret it. My take is that images are obviously important, but they have to be used very consciously, with an awareness of what they can and cannot do. Film speaks to us in one way and text in another. I’m interested in how they may work together.”

Chio began filming the villages in “农家乐 Peasant Family Happiness” in 2006 as part of her thesis for a PhD in socio-cultural anthropology at the University of California, Berkeley.

Domestic tourism is booming in China. As the middle class has blossomed in cities, the government has promoted tourism in the countryside, to help address the vast economic disparities between the urban and rural populations. The term “peasant family happiness,” or nong jia le, became a catch-all phrase to describe the phenomenon of homestays and guesthouses where “city slickers” can unwind while enjoying local food and activities.

Chio turned her camera on two ethnic minority villages cultivating tourism in their largely agricultural and wage-labor economies. The first, an ethnic Zhuang village called Ping’an in the terraced rice fields of mountainous Guangxi Zhuang Autonomous Region, has been on the tourist map since the 1980s, due to its dramatic scenery. The second, Upper Jidao Village in Guizhou Province, is an ethnic Miao community with a quieter beauty. Set at the foot of a hillside in front of a river, Upper Jidao was just beginning to transform itself into a tourist destination when Chio started filming.

A villager at work in a rice field. Photo by Jenny Chio.

Here’s an excerpt of a review of  Chio's documentary, published by the journal American Anthropologist:

“The film opens with some striking footage of tourists being carried up steep slopes in colorful canopied bamboo sedan chairs. Ping’an men keep tallies on whose turn it is to carry the next passenger at the sedan chair boarding station. From an observation point, a tour guide in ethnic dress armed with a microphone rallies the tour group, consisting of urban Chinese tourists, to admire the rural landscape.” 

“It’s fascinating to me all the types of labor involved in creating and maintaining tourism in these villages,” Chio says. “The visitors must be fed and entertained. And the villagers have to learn how to re-visualize their living spaces and environments. Jeans and t-shirts, for example, may be cheaper, but the tourists expect to see villagers in ethnic dress.”

The tourists may want to have a cultural experience, but they don’t necessarily want it to include strong smells. In order to create a guesthouse, village families must consider whether they need to move their pigs away from their traditional location, beneath homes, to pens further away.

A flush toilet and indoor plumbing, uncommon luxuries in many villages, are basic essentials for city folk. Windows may need to be screened, and a balcony added to a room to make it more desirable. A concrete house may be more practical, and less of a fire hazard, but a wooden home is more picturesque.

One of Chio’s favorite scenes from the film shows about two dozen men from Ping’an strapping a 2,000-kilogram electrical transformer to two tree trunks, then hefting the trunks to their shoulders and carrying the transformer up a steep slope. “I don’t actually explain what’s going on to the viewers,” Chio says, “but, of course, if you’re going to bring more electrical capacity to an 800-meter-high village with only footpaths and one narrow road, then you are going to have to pack in a larger transformer. When the men finally arrive at the place where they can set it down, you hear this collective groan and cheer that sounds so tired and full of relief. It was a pretty amazing, joyous moment for the village.”

Residents of Upper Jidao and Jenny Chio pose with "minority models" for a souvenir photograph in Ping'an.

A major benefit of tourism is that it can allow families to stay in ancestral villages and keep their home and land. “I’m very much a product of the American suburbs,” Chio says, “but in rural China people have really strong ties to their land. The young adults of a family may go into the city and work, but many of them return for holidays and they talk about wanting to come back to their villages permanently.”

As more village youth graduate from college, rural tourism gives them an opportunity to return and run a hotel or other business. “They may help their parents create web sites for a guesthouse and build networks with travel companies,” Chio says.

Among the negative effects of tourism are environmental problems. “Tourism uses a lot of resources, like water and energy,” Chio notes. “It also makes village residents much more aware of the inequities between rural and urban parts of the country.”

China’s population recently tipped for the first time into a predominantly semi-urban-to-urban one, but 49 percent of the country remains rural.

“Rural China sits at the heart of a lot of key issues that the government has to deal with,” Chio says, including political instability at the local level, the critical need for food security, population mobility and tensions between the “haves” and “have nots.” The rapid urbanization of China has put more pressure on the government to help the countryside catch up.

Chio’s next project is focused on the digital technology and media practices of rural China. In some areas, non-governmental agencies have been training villagers in video production. The videos appear to have varying aims, from fostering awareness of social issues and environmental problems to simply offering glimpses of local festivals and other events.

“Making short, home-movie-style videos of local ethnic life is becoming a part of everyday life in rural China,” Chio says. “People are selling some of these videos at street stalls and in shops. I want to learn more about what these videos portray, who is making them, and who is buying them.”

On the gruesome trail of syphilis, then and now

A woodcut from about 1497 shows a physician treating a patient with syphilis, one of the earliest known depictions of the disease.

Tracking the origin of syphilis, and related treponemal diseases, has taken Emory anthropologist George Armelagos and his graduate students across the globe and through time, from the voyage of Christopher Columbus to the forests of West Africa where modern-day monkeys suffer from a vicious form of yaws. Armelagos co-wrote an article for The Scientist summarizing the work with two of his former Emory graduate students: Kristin Harper, now a researcher at MetaMed, and Molly Zuckerman, who is now an assistant professor at Mississippi State University. Below is an excerpt from the article:

"By the close of the 15th century, chaos reigned in Naples, Italy. At the invitation of Pope Innocent VIII, the French King Charles VIII invaded the city with 25,000 troops. Soon after, a terrible new disease appeared among the soldiers and the prostitutes who accompanied them. Boils as big as acorns that burst and left scabs, terrible joint pain, rotting flesh, and a revolting odor tortured the infected. By the dawn of the 20th century, it was estimated that as many as 10 percent of London residents, 15 percent of Parisians, and 20 percent of US army recruits had the disease—dubbed syphilis after the hero of a 16th-century poem who is afflicted with the infection as a punishment for insulting the god Apollo.

A CDC micrograph of T. pallidum.

"The pale, corkscrew-shaped bacterium responsible for the outbreak, Treponema pallidum, was identified in 1905, and the prevalence of the infection plummeted in the developed world after the discovery of antibiotics. Still, roughly 12 million people are diagnosed with syphilis each year, and it remains an important public health problem in low-income countries.  ...

"Recently, many researchers, our group included, have taken a new approach to the study of the origin and evolution of syphilis and its cousins, and the breadth of these diseases’ reach today. Leveraging techniques from genetics, biological anthropology, and wildlife disease ecology, syphilis researchers are now beginning to answer questions that have been pondered for hundreds of years. The skeletal, genetic, and ecological information scientists are now uncovering could inform our understanding of how T. pallidum has evolved and how we can best control it today."

Read the whole article in The Scientist.

Related:
Skeletons point to Columbus voyage for syphilis origins
Penicillin, not the pill, may have launched the sexual revolution