Category: Lemurs Page 3 of 4

Schmitt Blends Locomotion and Arthritis

On January 10, 2014

In Animals, Biomedical Engineering, Guest Post, Lemurs, Science Communication & Education, Students

Guest post by Joseph Kirollos, NC School of Science and Math

Walking up to the Trent Semans Center at Duke University to interview Dr. Daniel O. Schmitt, professor of Evolutionary Anthropology and teacher of anatomy at Duke University, I couldn’t help but wonder why he would pursue seemingly unrelated interests. On one hand, he studies the locomotion and evolution of primates while at the same time, he but he also has a strong clinical interest in both human functional anatomy and osteoarthritis.

Dan Schmitt with his wife, Christine Wall, who is also an evolutionary anthropologist at Duke. (Duke Chronicle photo)

How did these interests come about? Which came first? These were the questions that ran through my head as I read through his papers and prepared for the interview. Though as Dr. Schmitt sat down and began to tell his story, it didn’t take long for all of my doubts and confusions to quickly fade away. Everything began to blend, and it all made sense.

As it turns out, Dr. Schmitt was actually a latecomer to clinical research and it was through natural variance and human evolution that science first captivated his interest. Although he was somewhat of a “terrible college student,” he quickly developed a genuine curiosity in the vast physical differences between species. It was later during his graduate studies at SUNY Stony Brook, where he worked with live animals, that he became a post-doc drill associate in anatomy and began to wonder how factors such as leg design, pelvis width, or even high metabolism affected how humans and animals move. By asking these questions, he expanded his interests to the next level and created a stepping stone that would lead him into both his evolutionary and clinical research.

[youtube http://www.youtube.com/watch?v=VA8diXNvffY?rel=0]

At the locomotion lab at Duke University, where he continues to research today, he was able to delve headfirst into Evolutionary Anthropology as he studied the selecting factors that govern limb design, gait mechanisms, and energy efficiency of locomotion in primates and humans. One of his main interests even today is the origin of human’s unique design and bipedal locomotion.

Schmitt, who teaches anatomy to medical students, went to the Duke-NUS graduate medical school in Singapore in 2012 to talk about medical education with colleagues. (Duke-NUS)

In fact, the first of his papers that caught my attention dealt with this very topic. It was a paper refuting the commonly accepted theory that humans evolved from terrestrial knuckle-walking primates such as gorillas and chimpanzees rather than tree-climbing ancestors (see the paper here). As I discussed the paper with Dr. Schmitt, he revealed that he normally preferred to avoid controversy, yet, in this case, he felt that he couldn’t “buy into” the fact that humans would evolve from terrestrial knuckle-walking ancestors. He said, “I couldn’t think of one good reason for them to stand up.” Interestingly, the paper analyzes features from the human wrist that previously supported knuckle-walking ancestors and turns it around and says that in fact these features actually may support that we had tree-climbing ancestors. However, in person, Dr. Schmitt referred to this argument as being rather “nihilistic” as it challenges an idea but doesn’t really propose an alternative.

Of course, it was only a matter of time before these interests in both human anatomy and the evolution of biomechanics in primates naturally brought him to wonder how human joints have so uniquely and efficiently adapted. Working with Dr. Ershela Sims, he has studied osteoarthritis in humans, a debilitating and widespread disease of the joints, and today he still explores the factors that cause it.

I found this quite interesting as my family has a long history with severe osteoarthritis. Interestingly Dr. Schmitt said that it was not intervention and treatment that he cared about, but rather he was interested in the basic science, the deeper causes that lead to osteoarthritis. Is there more than just obesity and wear and tear that leads to osteoarthritis and how does it affect human movement? These were the questions that he would ask. Naturally this blended quite well with his gait studies with primates as osteoarthritis affects the gait mechanisms and energy efficiency of humans. So by the time our discussion had finished, I felt a little dumb that I previously felt as though Dr. Schmitt had an unusual range of interests. I realize now that they blend in perfect harmony, each inspiring the other, leading to amazing discoveries.

Joseph Kirollos interviewed Dan Schmitt and wrote this post as part of a Science Communication seminar led by NCSSM Dean of Science Amy Sheck.

Battling Doubt and Danger in the Amazon

By Erin Weeks

On December 4, 2013

In Animals, Field Research, Lemurs, Science Communication & Education

Patricia Wright’s interest in owl monkeys was the launchpad for her renowned career in primatology (Photo: Steven Walling)

By Erin Weeks

One night, during her routine survey of nocturnal monkeys in the Peruvian rainforest, Patricia Wright came nose to nose with a large, male jaguar. She edged slowly off the trail, but she knew the big cat was the one who would decide if she would live to see daylight. He could either jump toward or away from her, Wright says. This time, he jumped away.

Wright’s encounter with the elusive jaguar is just one of many adventures recounted in High Moon Over the Amazon, a memoir covering her early life and research on South American monkeys.

Though best known these days for her pioneering work on Madagascar’s lemurs, Wright’s path to science wasn’t always so clear. In the late 1960s, when her contemporaries were getting PhDs, Wright worked in social services before quitting to raise her daughter. The chance purchase of an owl monkey–and Wright’s insatiable curiosity about the mysterious species’ habits–set her off on a remarkable journey from hippie housewife to groundbreaking researcher.

Wright told that story last night at an event sponsored by the Duke Lemur Center, which was the first place she worked after eventually obtaining her own PhD in her 40s. She read passages about the time army ants ate through her camp’s storehouse and about the difficulties of balancing single motherhood and doctoral work. Wright’s tenacity in the face of doubt and danger kept surfacing in her talk and is something she’s said she hopes to inspire in young women interested in scientific careers.

“Not giving up is the key, and I think young women of today should know that it might not be easy, but they should not get discouraged, because in the long run the struggle is worth it,” she said in an interview with NPR.

Dr. Patricia Wright (Photo: Noel Rowe)

Early Primate Leaping Set Stage for Human Airtime

By Ashley Yeager

On July 3, 2013

In Animals, Behavior/Psychology, Biology, Faculty, Lemurs, News Release

By Ashley Yeager

From primate ancestors that leaped like a dwarf lemur is where we got our ability to jump, a new study suggests. Photo courtesy of Mireya Mayor.

Primate ancestors that leaped like a dwarf lemur may be where we got our ability to jump, a new study suggests. (Photo courtesy of Mireya Mayor and Shaquille O’Neal).

Over a puddle, up to the basket, off the high dive — we all take leaps from time to time.

Now, new research suggests that this acrobatic lifestyle began far back in our evolution, when the earliest primates were first emerging on Earth.

“What this study suggests to us is that a very unusual and impressively acrobatic lifestyle jumping through the trees set us on the road to evolving many of features we recognize today in primates, including humans,” says Duke evolutionary anthropologist Doug Boyer.

Boyer and colleagues measured the ankle bones of 73 living and 38 extinct species of primates and found that throughout primate evolution, even our earliest ancestors were developing the bone structure to support long jumps. The results appear July 3 in PLoS ONE.

From the data, the scientists concluded that the ankle mechanics for better leaping in primates began to evolve around 55-60 million years ago. Boyer says natural selection seemed to favor a lifestyle of increasingly acrobatic locomotion in trees, including leaping long distances rapidly between branches.

Scientists had previously noticed that exceptional leapers had unusually elongated ankles. Boyer’s study, however, is the first to simultaneously test for effects of both body mass and behavior on ankle-bone elongation.

The team found a trade-off between body mass and ankle elongation. At larger body masses, ankles were proportionally shorter regardless of behavior. Yet, among animals of similar body size, the leapers had proportionally longer ankles, Boyer says. This was true among even fairly large primates, a contradiction to scientists’ earlier view that there was no behavioral benefit of ankle elongation for bigger animals.

The study is also the first to look at incremental evolutionary changes leading from our earliest primate ancestors to all the modern living forms. Whether leaping was an important behavior for the earliest primates has been controversial.

From their fossil data, Boyer and colleagues could see that early primates were not specialized leapers. “For the most part many of them were generalists, clamoring around on trees, jumping around now and then, but possibly preferring to scamper rather than make huge leaps,” he says.

The ankle bone serves a fulcrum to launch leapers’ into the air. The longer the lever, the better the jump, in most cases. Credit: Doug Boyer, Duke.

This particular conclusion was not new. But the researchers’ approach — looking at incremental evolution — allowed them to see more of a change. “The earliest primates were already better leapers than their ancestors, and the data show their descendents became even better yet,” he explains.

The measurements also suggest that initial elongation of the bones for specialized leaping evolved two independent times in primates – once in lemur ancestors and once in the ancestor of tarsiers, monkeys, apes and other anthropoids like us.

The study didn’t directly address human leaping, and it doesn’t mean humans with longer ankles are better leapers. But, Boyer notes, it’s not out of the range of possibility.

Citation: “Evolution and allometry of calcaneal elongation in living and extinct primates.” Boyer, D. et al. July 3, 2013. PLoS ONE. doi: 10.1371/journal.pone.0067792

Fossil Primate Director Becomes a Fossil Primate Himself

By Karl Bates

On May 20, 2013

In Animals, Biology, Faculty, Lemurs

Gregg Gunnell directs the fossil primate division of the Duke Lemur Center.

By Karl Leif Bates

A newly discovered 25 million-year-old monkey fossil has been named for Gregg Gunnell, director of the Duke Lemur Center’s Division of Fossil Primates.

The thing is, Nsungwepithecus gunnelli, might turn out to be a pig. “It might be a ‘porky-pithecus,’ ” Gunnell said with a laugh. “Early monkeys and early pigs looked remarkably alike.”

The fossil, from southwestern Tanzania, consists of a single molar. But it displays nine characteristics that would distinguish it from other Old World monkeys, according to Nancy Stevens, a paleontologist at Ohio University in Athens, Ohio who was the lead author on a paper about the discovery in Nature.

Gunnell’s monkey was found at a site in the Rukwa Rift Basin along with another new monkey fossil, Rukwapithecus fleaglei, for which scientists have a jaw and three teeth. It too has nine distinguishing features.

An artist's conception of the two newly named 25.2 million year old fossil monkeys described in Nature. (credit: Mauricio Anton)

An artist’s conception of the two newly named 25.2 million year old fossil monkeys described in Nature. Gregg Gunnell is the guy on the right. (credit: Mauricio Anton)

Gunnell said Stevens named the monkey after him to honor his role in helping her become a paleontologist. When Stevens was an undergraduate at Michigan State University, and Gunnell worked in the museum at the University of Michigan, he took Stevens and her now-husband and co-author Patrick O’Connor along on archaeological digs in Wyoming. Apparently the lessons stuck.

N. gunnelli is actually Gunnell’s third species. He was earlier honored by the naming of a bat and an extinct tillodont, which was, he reluctantly explains, a rather pig-like little animal.

“I’m hoping that this pig really is a monkey — that’ll improve my self-image,” he said.

Learn more

Activist targets inner child not 'target audience'

By Ashley Yeager

On March 4, 2013

In Animals, Behavior/Psychology, Business/Economics, Climate/Global Change, Environment/Sustainability, Faculty, Lemurs, Science Communication & Education, Visualization

By Ashley Yeager

A baby albatross carcass full of plastic “food.” Credit: Chris Jordan.

When artist Chris Jordan works on a photograph or film, he doesn’t think about his audience. He said he thinks the phrase “target audience” is a disrespectful, manipulative business concept.

“I want to be as authentic as possible with my work,” Jordan said, explaining that each of his pieces instead taps into that “universality in us that we all carry, a deep appreciation for the abiding beauty of our world and the miracle of our own lives.”

An environmental activist as well as an artist, Jordan is challenging others to target that universality too as they convey messages about the issues that affect the planet.

Jordan spoke March 1 as part of a working group to discuss questions about how environmentalists, neuroscientists and artists can work together to better communicate about issues affecting the planet. The Nicholas School of the Environment and the Duke Institute for Brain Sciences sponsored the discussion.

Duke ecologist Nicole Heller moderated the discussion, opening it with the idea that scientists are frustrated with their inability to communicate with politicians and the public about the environment.

“In the ’70s, yucky or scary images might have worked, but now they don’t. That’s no longer appealing. We need different kinds of imagery to reach across people’s biases,” Heller said. She invited Jordan to speak because of his reputation for being able to move audiences from diverse backgrounds and education levels.

“Second graders are some of the most passionate and responsive to these issues,” Jordan said, adding that perhaps the best thing we can do is to appeal to an individual’s inner child – that curious spirit we have to understand how the world works.

One example of this approach is the film Jordan is working on to explore the mating dance of albatrosses on Midway Atoll in the Pacific Ocean. He’s photographed dead baby albatrosses, whose stomachs are full of plastic trash their parents fed to them because they mistake the plastic for food. The work was to make people aware of the plastic vortex, or Great Pacific Garbage Patch, swirling beyond the horizon and therefore beyond our conscious concern.

Jordan decided to capture the wonder of the albatrosses as they mate, rather than just their rotting carcasses, hoping to feed his audiences — no matter their background — with life, rather than depress them with death.

“Like the albatross, we first-world humans find ourselves lacking the ability to discern anymore what is nourishing from what is toxic to our lives and our spirits. Choked to death on our waste, the mythical albatross calls upon us to recognize that our greatest challenge lies not out there, but in here,” Jordan writes on his Web site.

Lemurs Most Threatened Mammals on the Planet

By Karl Bates

On July 24, 2012

In Animals, Biology, Environment/Sustainability, Lemurs

By Karl Leif Bates

Things seem to be going from bad to worse for the lemurs of Madagascar.

A report issued two weeks ago by a working group in Antananarivo, Madagascar’s capital, concludes that these prosimian primate cousins of ours are THE most endangered mammals on the planet with 91 percent of all lemurs on the Red List of threatened status.

The 5,000-acre Betampona Nature Reserve in the eastern rainforest region is the smallest and oldest of Madagascar's officially protected areas. It looks like a green island surrounded by damaged forests and subsistence farming. The reserve is jointly managed by the Madagascar Fauna Group, of which the Duke Lemur Center is a founding partner, and was the site of first reintroduction of lemurs which had been bred in captivity at DLC.

In a poor and poorly governed country, humans are steadily chewing away at lemur habitat and at the lemurs themselves.

One species, the northern sportive lemur, is down to just 18 individuals on a tiny speck of habitat at the extreme northern end of the island. There are none in captivity.

“When these species disappear from Madagascar, they are lost forever,” Lemur Center Director Anne Yoder said. Captive breeding programs, like the one at the Duke Lemur Center, are a poor substitute for the protection lemurs really need.

The warning is unfortunately all too familiar to the faculty, staff and volunteers of the DLC, and it casts their work in conservation, education and research as even more critical.

In addition to its crucial work in Durham, DLC has been working on the ground in Madagascar for more than 20 years to preserve habitat and build a corps of conservation-minded citizens. Post-doctoral researcher Erik Patel participated in the Antananarivo workshop and reported on the meeting last week.

Learn More:

Anne Yoder and Charlie Welch on Duke Lemur Center blog.

Russ Mittermeier, chairman of the Madagascar Primate Specialist Group and President of Conservation International in the Huffington Post.

The Duke Lemur Center's breeding population becomes ever more important as wild lemurs disappear.

Kratt's Creatures come to life

By Ashley Mooney

On April 3, 2012

In Animals, Lemurs, Science Communication & Education

By Ashley Mooney

Duke alumnus Martin Kratt detailed his journey from his time as an undergraduate throughout the creation of several wildlife shows targeted toward children.

Kratt spoke Monday to a crowd of students, wildlife enthusiasts and some of his younger fans about his roots in wildlife conservation. With his brother Chris, Kratt created several wildlife television shows—including Kratts’ Creatures, Be the Creature and Wild Kratts—as a way to aid education and preservation of endangered species. Several of his roots tie back to Duke, namely the star of his popular show Zoboomafoo, which featured Jovian, a captive Coquerel’s Sifaka from the Duke Lemur Center.

Kratt got his start as a student technician at the Lemur Center—then known as the Duke Primate Center—in his junior year.

Jovian, the Coquerel's sifaka who played Zoboomafoo. Photo courtesy of David Haring from the Duke Lemur Center.

Although he initially wanted to be a conservation veterinarian, he credited his beginning in wildlife television to a class at Duke called amphibian ecology. Kratt borrowed an underwater camera and filmed salamanders during class field trips, creating a video on the amphibians for another class he had been taking for fun. His film ended up winning the Hal Kammerer Memorial Prize for Film and Video Production.

“Every weekend our professor would take us on field trips to the coastal plains of Piedmont to the Smokey Mountains—looking for salamanders, that was the course,” he said.

He joined Ken Glander, professor of evolutionary anthropology, on a research trip to Costa Rica. There, Kratt helped Glander catch Howler monkeys amidst the dry northern rainforest. He remained in Costa Rica for an additional six months, filming the wildlife in the area.

“We started taking these videos . . . to elementary schools in New Jersey. We sat and ate pizza at lunch, asking them what they liked and what they didn’t like. And the great thing about kids: They are honest critics,” he said. “Overall, they liked it, from kindergarten to fifth grade.”

Despite positive reviews from their younger audience, several networks did not find the Kratt brothers’ idea feasible.

“One comment we got from National Geographic was, ‘it’s cute but it will never be a TV show.”

Despite many setbacks, Kratt created a known collection of children’s wildlife programs. His new endeavor, Wild Kratts, aims to teach kids about animal behaviors that are known or suspected to exist, but have never been caught on camera.

“There’s animal behaviors that nobody’s ever seen, for example sperm whales fighting colossal squids,” he said. “If we did a series using animation we can show all of these behaviors that eluded us.”

This idea evolved into the current series Wild Kratts. The show is now ranked number eight in ratings of animated shows, two spots ahead of SpongeBob, Kratt said.

“We’re all working together [to help endangered species]. Scientists are studying to gather new information; educators are educating [and] policy makers can make policy,” he said. “Everybody can find their own path and their own way to help save endangered species.”

Meet Joel Bray, Lemur Enthusiast

By sa160@duke.edu

On March 20, 2012

In Animals, Behavior/Psychology, Lemurs, Students

By Nonie Arora

Joel the Lemur and the rest of the Crazies meet Dick Vitale at the March 3 UNC game. (Duke Photo)

You may have been wondering who the student dressed as a lemur was for the Duke-Carolina game. Meet Joel Bray, lemur enthusiast and Trinity Junior.

Joel works in Brian Hare’s cognitive psychology lab where he does research on the psychology and evolution of nonhuman primates.

“Primates are an amazing way to understand human behavior, and specifically cognition,” Bray says. He studies lemurs at the Duke Lemur Center, which is home to the largest population of lemurs outside of Madagascar. Lemurs, most similar to the last common ancestor of all primates, are interesting because all 100 species are closely related at the genetic level, but they live in very different social and ecological environments.

In his first project, Joel studied inhibitory control in lemurs to understand how cognition evolves. This was part of a larger effort under NESCent, the National Evolutionary Synthesis Center. The project sought to compare dozens of species, including primates, birds, and rodents, on the same tasks using the same methods.

Joel tested the lemur’s inhibitory control by presenting them with an opaque cylinder with openings on both ends and food inside. The animals first learned how to retrieve the food. Then, the opaque tube was replaced with a transparent one. The impulse is to reach directly for the food item through the obstructed barrier, but to successfully retrieve the food the lemurs had to inhibit that response and reach from the side. Inhibitory control is considered to be important in both social and foraging contexts, and certain environments are expected to exert more selective pressure for the ability. In human children, it is predictive of future academic and social success.

Joel, out of costume, studies a troop of ringtailed lemurs because he's a method actor. (Courtesy of Joel Bray)

More recently, Joel has investigated social cognition, specifically asking what lemurs understand about the perception of other individuals. Humans display “theory of mind,” the notion that other individuals have perceptions, knowledge, and beliefs different from one’s own. While lemurs are unlikely to have a complex understanding of the minds of other individuals, they may display more basic abilities.

In his current project, Joel is asking whether lemurs will take advantage of information about a human competitor’s visual perspective to acquire food. One food item is visible to the experimenter and the other is not, and the lemur must decide which to approach. It is expected that that species in large or complex social groups will perform better because their evolutionary history has selected for being able to understand what other individuals can perceive (i.e. “social intelligence”).

Ultimately, this research may lead to a better understanding of human cognition and whether our “big brains” evolved because of complex social environments.

A Festival of Lemur Babies

By Karl Bates

On September 12, 2011

In Animals, Biology, Lemurs

Ichabod the baby Aye-Aye was the somewhat nervous 2008 result of a painstaking 2-year effort to teach his sire how to make babies.

A BBC Television production called “Miracle Babies” is airing this week on the Nat Geo Wild cable channel, with two segments about the captive breeding programs at the Duke Lemur Center. Their crew travelled all over learning about captive and not-so-captive breeding programs – all of which seem to result in adorable infants, strangely enough!

Tuesday, Sept. 13 at 10 p.m. Eastern on National Geographic Wild, learn about DLC’s efforts to breed nocturnal, bug-eating Aye-Ayes. (The male needed more than mood lighting to figure things out, let’s just put it that way. )

Then on Wednesday Sept. 14 at a more reasonable 8 p.m., they check in again with a segment about the stunning Coquerel’s sifakas and their spindly little infants. View the complete schedule.

Preview here: Miracle Babies Preview

Coincidentally, the Lemur Center posted a baby video of its own over the weekend, starring an impossibly small baby mouse lemur and its mum.

See it here: Mouse Lemur baby

Lemur film features future Duke post-doc

By Ashley Yeager

On September 8, 2011

In Animals, Biology, Environment/Sustainability, Field Research, Lemurs

Primatologist Erik Patel studies the endangered silky sifaka, seen here. Credit: Erik Patel.

Primatologist Erik Patel is trying to study and save a cute lemur called the silky sifaka (Propithecus candidus).

In a recent online documentary, he takes viewers through Marojejy National Park, a 148,387-acre area of jungle with rugged mountainous terrain, and gives them a rare, up-close look at the silky in its wild habitat.

These lemurs are most at risk of extinction, which is one of the reasons Patel studies them, and, as the documentary shows, the illegal logging and bushmeat trade are likely accelerating the loss of the lemurs’ habitat and their overall population.

Patel, who will join Duke’s Lemur Center in January, told the New York Times that “stopping illegal logging in Madagascar will be impossible until the government stabilizes and some measure of accountability is put in place.”

“It’s about money,” as the individuals in government are now “organizing and profiting from the problem,” he told the Times reporter.

One of Patel’s roles when he joins Duke will be to oversee the Lemur Center’s new conservation initiative to help individuals in cities near Marojejy understand and value the distinct environment and animals found only in their country.

Watch the full feature here.