Monday, March 31, 2014

For the love of lemurs and Madagascar

The IMAX movie “Island of Lemurs: Madagascar” opens nationwide on April 4, including Atlanta's Fernbank Museum of Natural History. Mouse lemurs, above, are among those featured in the film about the island, a bio-diversity hotspot.  (Photo by Frank Vassen)

By Carol Clark

“I smell props,” says Sarah Zohdy, a biologist in Emory’s Department of Environmental Sciences and the Rollins School of Public Health. She looks skyward, scanning a tangle of thick Tarzan vines, tree branches and leaves that weave the dense rainforest canopy 100 feet above.

“Do you smell that?” Zohdy asks a new arrival to Madagascar’s Ranomafana National Park. “They have a scent like maple syrup.”

Then, whoosh! A wide-eyed, fur-covered acrobat, mostly arms, legs and tail, leaps out of one clump of leaves and disappears into another.

“Props!” Zohdy confirms, smiling at the comical effect of the creature. “Their legs are crazy long for their bodies.”

Propithecus edwardsi
Propithecus edwardsi, more commonly known as a sifaka, is one of nearly a hundred species of lemurs. These primitive primates, with large, round eyes and wet, dog-like noses, are unique to Madagascar, an island in the Indian Ocean, off the southeast coast of Africa.

Lemur ancestors arrived in Madagascar some 65 million years ago, perhaps floating over from mainland Africa on mats of vegetation. Isolated on the island, the Earth’s fourth largest, lemurs evolved independently from other primates, diverging into a striking cast of characters: From the teddy-bear cute black-and-white ruffed lemur to the creepy, bat-like aye-aye.

Zohdy’s favorite is the mouse lemur, the smallest primate in the world. “The adults weigh about as much as a fun-sized package of M&Ms and can fit into the palm of your hand,” she says. “The babies are no bigger than a Ping-Pong ball and, basically, all eyeballs.”

A new IMAX movie “Island of Lemurs: Madagascar,” opening nationwide on April 4, features the work in Ranomafana of famed primatologist Patricia Wright, one of Zohdy’s mentors. “The imagery in the film is so rich, it tugs on my heartstrings,” Zohdy says. “I hope the film makes more people around the world aware of the dire ecological situation in Madagascar.”

Watch the trailer for the IMAX movie:

Zohdy has been researching lemurs in Madagascar for seven years. Last summer, she broadened her focus and led an Emory infectious disease field team in Ranomafana, made up of students from a range of specialties. The Emory team is gathering baseline data for an ambitious “one health” intervention. The goal is to bolster the health of the rural poor around Ranomafana, who are struggling to stay fed, sheltered and alive, while also conserving the ecosystem of the World Heritage site.

Zohdy’s rubber boots make loud sucking sounds as she trudges through thick mud towards a wooden suspension bridge spanning the Namorona River, roaring and rushing over its rocky bed even during the dry season.

“Check out that spider web,” she says, as she leads the way across the bridge. She points up at gossamer threads hanging above the water, leading out of the forest on one side of the river and stretching 40 feet to connect with the trees on the opposite bank. The recently discovered Darwin’s bark spider, she notes, spins the largest webs in the world, and its silk is the toughest biological material ever studied, more than 10 times tougher than Kevlar.

Crested drongos – large black birds sporting what look like elegant coattails and fancy feather headdresses – chatter in the trees alongside the slick forest trail, which is now leading steeply up a lush hillside.

Zohdy pauses when she hears breaking leaves in the canopy and catches a whiff of a musky, zoo-like smell. “Golden bamboo lemurs. They are right above us,” she says softly. “Don’t open your mouth when you look up,” she quickly adds. “People have been peed on.”

A golden bamboo lemur, photographed in Ranomafana by Sarah Zohdy.

The dusky-gold creatures, which look like a cross between a Koala bear and a raccoon, are critically endangered. They are one of three species of lemurs in the park that subsist almost entirely on the tender leaves and shoots of bamboo.

The greater bamboo lemur is the rarest of them all. Just two remain in the 160-square-mile Ranomafana National Park – a father and his daughter – and only about 60 survive in the wild. Like the giant panda, the greater bamboo lemur has molars capable of slicing and crushing the tough trunk of bamboo.

“It’s a fascinating evolutionary adaption,” Zohdy says, that allows them to survive during the dry season, when the more tender bamboo shoots and leaves are not as readily available. Loss of habitat and shifts in climate, however, have lengthened the dry season. “That means the greater bamboo lemurs have to chew on the tough trunks longer, which wears down their teeth,” Zohdy says. “When their teeth go bad, they starve. It’s not like they can go to a bamboo lemur dentist and get dentures.”

Since humans began settling on the island, only about 2,000 years ago, bringing a rice-growing culture with them, much of the natural habitat and its wildlife has disappeared, including at least 17 species of lemurs.

“When I first came to Madagascar, I thought the whole island would look like a BBC nature special,” Zohdy recalls. Instead she was stunned during the ten-hour drive from the capital of Antananarivo to Ranomafana to see a largely treeless landscape of terraced rice paddies and the occasional smoke from slash-and-burn agriculture.

Watch a video about an Emory "one-health" project in Madagascar:

In the steep landscape of Ranomafana, the homes of villagers and their food crops and livestock bump up against the remaining patches of primordial wilderness. The crowding puts both people and animals at risk. “When you have humans encroaching on wildlife habitat you have huge potential for zoonotic diseases, and the emergence of new diseases,” Zohdy says. Pneumonic plague and virulent strains of flu are examples of deadly outbreaks that have occurred in Madagascar in recent years.

The “one health” approach of the Emory infectious disease team may be key to solving some of the complex problems facing the Malagasy people and the fragile Ranomafana ecosystem. “To really understand human health, animal health, and environmental health, you have to study all three at once,” Zohdy says.

During the summers, going back to 2011, Emory student-researchers have collected fecal samples of lemurs, people and their livestock. These samples, along with mosquitos and ticks the team is collecting, are sent back to Atlanta for analysis of pathogens they may contain.

The project is part of a large-scale effort of conservation and global health being coordinated by Thomas Gillespie, an Emory professor of Environmental Sciences and Environmental Health. The data the students are gathering will help guide a health care improvement effort through a new non-profit agency called PIVOT.

Madagascar is home to half the world's chameleon species. Photo by Sarah Zohdy.

One evening, Zohdy leads students on the team on a night hike up the side of a mountain. The forest is eerily silent. A thick mist snakes along the ground and drifts up through the silhouettes of trees.

The researchers’ headlamps slice like lasers across the understory, occasionally striking treasure. An iridescent green and blue chameleon looks like a jeweled dragon clinging to the branch of a sapling. A golden moth the size of a small bird fans its wings across a clump of eucalyptus leaves.

“Do you hear that high-pitched trill, like a tiny, far-away bell?” Zohdy asks. “That’s a mouse lemur.”

Tiny pairs of glowing eyes pop out of the darkness. Mouse lemurs are nocturnal, and their eyes shine due to the reflective effects of sensitive night vision. The eyes appear, then vanish in a flash, as the shy creatures dart amid the branches of small trees.

Zohdy instructs everyone to switch their headlamps from white light to red, so the lemurs don’t get blinded.

Seen in well-lit photographs, the brown mouse lemurs populating Ranomafana are charming. They have a beguiling gaze and tiny, elegant hands that look more human than animal, complete with delicate fingernails.

Moving through the dark forest, however, these miniature primates become like lemures, Latin for ghosts and the origin of the word lemurs. They flit through the trees alongside the trail, watching the humans with wide, curious eyes that reflect the red glow of the curious humans watching them back.

 Watch a video about the making of the IMAX movie:

In Madagascar: A health crisis of people and their ecosystem

Thursday, March 27, 2014

If Carl Sagan had been a dancer

Theater Emory and the Emory Dance Program premiere their first collaboration, "Free/Fall: Explorations of Inner and Outer Space," on April 3 in the Mary Gray Munroe Theater.

"When astronomers talk about the cosmos, you often hear words or phrases that describe behaviors, moods, relationships, even arcs and journeys and sudden eruptions of 'emotion,'" says director Janice Akers, explaining the inspiration behind the production. "The language also has highly physical imagery: rotation, orbiting, colliding, intersecting, floating, coming towards, flying away."

Read more about the production here.

Wednesday, March 26, 2014

Festival gets all fired up for science

First-year chemistry students demonstrated the wonders of science in Emory labs last Saturday, to help launch the Atlanta Science Festival. More than 80 different organizations, including Emory, are collaborating on the week-long festival, made up of dozens of events throughout metro Atlanta, including many on the Emory campus. The festival culminates on Saturday, March 29 with a family friendly "Exploration Expo" in the Georgia World Congress Center.

Photo by Emory Photo/Video

Tuesday, March 25, 2014

How molecules are a lot like birds

Emory chemist Jay Goodwin was featured in an interview by Ari Daniel of PRI's "Living on Earth." Below is an excerpt from the interview transcript:

ARI DANIEL: Once in a while, if you’re lucky, you catch a glimpse of something that gives away a secret of the universe. It’s like a window – up into the heavens and deep into ourselves. This is a story about someone who poked his head through just this kind of window, and we find him in Atlanta. It’s a perfect day here – Jay Goodwin walks over to a bench to sit down. And he can’t help but be reminded about a day just like this one, 5 years ago, in western Michigan where he used to live.

JAY GOODWIN: I was outside – I think I was going for a walk, just to kind of clear my head a little bit. I turned a corner, and I saw this flock of birds and they took off into the sky and they started to form a shape – sort of an amorphous shape. And it was one that was dynamic, and it was changing – but it had a boundary to it, like looking at a blob of oil in water.

DANIEL: It stopped Goodwin in his tracks. Several hundred birds pulsing and dipping and soaring to an invisible beat in the sky.

GOODWIN: It wasn’t clear what they were responding to – there weren’t any predator birds in the sky. And you never got the sense that there was anything that was directing it from within. There was no leader bird that they were all following. But just watching it was, well, it was beautiful.

DANIEL: Goodwin realized he had no way of predicting the flock’s behavior by simply taking lots of individual birds flapping their wings, and adding them up. Rather, it was something that emerged once all these birds threw themselves together. And it’s this notion of emergence – how really complex patterns and properties can arise from combining somewhat simple units – that now defines how Goodwin thinks about his real work. Chemistry.

Goodwin heads into his lab at Emory University. He’s a chemist here. And since seeing that flock, he’s come to appreciate how molecules are a lot like birds. That is – you get to know how the individuals behave and parade on their own, but then, you put them together. And often, something new and astonishing emerges.

You can read the whole transcript, and listen to the podcast, on the "Living on Earth" web site.

Chemists boldly go in search of 'little green molecules'

Thursday, March 13, 2014

Scent of the familiar: You may linger like perfume in your dog's brain

A nose for neuroscience: Zen, a golden retriever/lab involved in the study. Photos, above and below, by Helen Berns.

By Carol Clark

An area of the canine brain associated with reward responds more strongly to the scents of familiar humans than it does to the scents of other humans, or even to those of familiar dogs.

The journal Behavioural Processes published the results of the first brain-imaging study of dogs responding to biological odors. The research was led by Gregory Berns, director of Emory's Center for Neuropolicy.

“It’s one thing when you come home and your dog sees you and jumps on you and licks you and knows that good things are about to happen,” Berns says. “In our experiment, however, the scent donors were not physically present. That means the canine brain responses were being triggered by something distant in space and time. It shows that dogs’ brains have these mental representations of us that persist when we’re not there.”

When humans smell the perfume or cologne of someone they love, they may have an immediate, emotional reaction that’s not necessarily cognitive, Berns notes. “Our experiment may be showing the same process in dogs. But since dogs are so much more olfactory than humans, their responses would likely be even more powerful than the ones we might have.”

In 2012, Berns led the team that captured the first brain images of alert, unrestrained dogs, using harmless functional magnetic resonance imaging (fMRI), setting the stage for exploring the neural biology and cognitive processes of man’s best friend. He has shown that dogs have a positive response in the caudate region of the brain when given a hand signal indicating they would receive a food treat, as compared to a different hand signal for “no treat.” In humans, the caudate region is associated with decision-making, motivation and processing emotions.

Berns conducted the scent research with Andrew Brooks, also with Emory’s Center for Neuropolicy, and Mark Spivak, owner of Comprehensive Pet Therapy.

“Olfaction is believed to be dogs’ most powerful and perhaps important sense, making it an obvious place to explore canine social cognition,” Spivak says.

Kady, a lab involved in the study, shown training for the experiment in a mock-up scanner.

The experiment involved 12 dogs of various breeds. The animals had all undergone training to hold perfectly still while undergoing an fMRI scan. As they were being scanned, the subjects were presented with five different scents that had been collected on sterile gauze pads that morning and sealed in Mylar envelopes. The scent samples came from the subject itself, a dog the subject had never met, a dog that lived in the subject’s household, a human the dog had never met, and a human that lived in the subject’s household.

The familiar human scent samples were taken from someone else from the house other than the handlers during the experiment, so that none of the scent donors were physically present.

The dog scents were swabbed from the rear/genital area and the human scents were taken from armpits.

“Most of the dog owners and handlers involved in the experiment were women, so most of the familiar human scent donors were their husbands,” Berns says. “We requested they not bathe or use deodorant for 24 hours before taking the sample. Nobody was too happy about that.”

Except for the dogs, apparently.

The results showed that all five scents elicited a similar response in parts of the dogs’ brains involved in detecting smells, the olfactory bulb and peduncle. The caudate responses, however, were significantly stronger for the scents of familiar humans, followed by that of familiar dogs.

“The stronger caudate activation suggested that not only did the dogs discriminate the familiar human scent from the others, they had a positive association with it,” Berns says. “While we might expect that dogs should be highly tuned to the smell of other dogs, it seems that the ‘reward response’ is reserved for their humans. Whether this is based on food, play, innate genetic predisposition or something else remains an area for future investigation.”

An interesting twist: The dogs in the experiment that had received training as service/therapy dogs showed greater caudate activation for the scent of a familiar human compared with the other dogs. It is unclear whether this difference was due to genetics or had simply been fostered through the service/therapy training.

“We plan to do further research to determine whether we can use brain-imaging techniques to better identify dogs that are optimal to serve as companion animals for the disabled,” Berns says.

The training of service dogs is time-consuming and expensive, he says, and only about one-third of the animals that begin the process successfully complete it. Meanwhile, the waiting list for service dogs is long, and includes many wounded veterans.

“In addition to serving as companion animals for wounded veterans, dogs play many important roles in military operations,” Berns says. “By understanding how dogs’ brains work, we hope to find better methods to select and train them for these roles.”

The scent experiments were funded by the U.S. Department of Defense Office of Naval Research.

What is your dog thinking?
Neuroscientist explores how dogs love us
Multi-dog study points to canine reward center

Monday, March 10, 2014

When 'I' becomes 'we': Brain-to-brain interfaces

Emory scientists John Trimper (psychology), Paul Root Wolpe (Center for Ethics) and Karen Rommelfanger (neurology) wrote an opinion piece on the ethical implications of emerging brain-to-brain interfacing technologies for Frontiers in Neuroengineering. Below is an excerpt.

The idea of creating a direct connection between a human brain and a computer has a long history in science fiction. The development of brain computer interfaces (BCI), technologies permitting direct communication between a user's brain and an external device, began to become a reality in the 1970s, and have since captured the attention of scientists and the public alike. Initially conceptualized for military use—the initial work was funded by the National Science Foundation and the Defense Advanced Research Projects Agency (DARPA)—more recently BCIs have shown promise for therapeutic uses, providing hope for restorative and even enhanced human capacities.
Utilizing both invasive and non-invasive technologies, scientists are now capable of recording and translating activity from populations of neurons to operate external devices. In early 2013, the technology took a leap forward as researchers replaced the external computer connection with a second embodied brain, dubbing the approach “brain-to-brain” interfacing (BTBI). The direct transfer of information between two brains raises new and important ethical issues. We summarize the first two landmark studies in BTBI research, and then discuss ethical concerns relevant to BTBI as they are applied in clinical, research, and non-therapeutic domains.

Tuesday, March 4, 2014

Atlanta Science Festival to launch on March 22

Via Emory Alumni Association

Get in touch with your inner scientist at the Atlanta Science Festival (ASF), a weeklong celebration of local science and technology.

"From March 22-29 at more than 100 events throughout metro Atlanta, visitors will experience scientific innovation and transform their perspective on how science impacts nearly everything we do," says Sarah Peterson, a co-founder of the ASF and program coordinator for Laney Graduate School. 

Emory has been a partner in ASF from its beginning and is collaborating with more than 80 community partners on the interactive festival.

A variety of events will take place on and around the Emory campus including lab tours, panel discussions, film screenings, an opportunity to see the sun through a solar telescope, a celebration of the science of beer, and much more. Click here to see the complete list of Emory events, times and locations.

The festival will culminate Saturday, March 29 at Centennial Olympic Park with an Exploration Expo featuring family activities, experiments, pop-up interactive exhibits and games, including faculty, staff and students from Emory's science and math departments. The Exploration Expo will be from 11a.m. to 4 p.m., and admission is free.

"Whether you're a self-proclaimed science-lover or simply fascinated by the how the world works, we invite you to share in this celebration of 'the curious' in all of us," says Jordan Rose, associate director at the Emory College Center for Science Education. "There's something for everyone: comedy, art, poetry, food, lasers, stars, gardens, dinosaurs and more."

Photo courtesy San Diego Science and Engineering Festival.