Peter Klopfer, Civil Rights Activist and Co-Founder of the Duke Lemur Center, Died

Peter Klopfer, professor emeritus of Biology, civil rights activist and co-founder of the Duke Lemur Center, died on June 5 at the age of 95. He is survived by his wife, Martha, and their three daughters.

Klopfer helped develop the field of behavioral ecology — the study of animal behavior and its evolution — and made seminal contributions to our understanding of mother-offspring bonding. His research helped elucidate the now well-known role played by the hormone oxytocin in mediating affective bonds.

He later developed a passion for dwarf lemurs’ ability to hibernate, and led a multidisciplinary team including sleep specialists, geneticists, field ecologists and physiologists, all focused on the causes and consequences of lemur hibernation.

Anne Yoder, Braxton Craven Distinguished Professor of Evolutionary Biology and former director of the Duke Lemur Center, describes Klopfer as a visionary. "The brilliance of Peter's mind was exceeded only by the warmth and generosity of his heart."

His impact extended well beyond research. Shocked by the segregationist policies still in place when they arrived in North Carolina in the late 1950s, the Klopfers co-founded one of the first integrated schools of the South, the Carolina Friends School. 

His civil rights activism also led to the U.S. Supreme Court ruling that the Sixth Amendment right to a speedy trial applies to state courts as well as federal courts, a victory that impacted thousands of cases around the country. In 2009, Klopfer was awarded Duke’s Samuel DuBois Cook Award in honor of his civil activism.

“What I respected most about Peter was that he lived his values,” said Gregory Dye, executive director of the Duke Lemur Center. “He stood up for what he believed was right, even when the consequences were potentially severe. He looked out for others, mentored students and junior colleagues, and provided guidance when I was first appointed the Lemur Center's executive director.”

Though much of Klopfer’s research took place at the Duke Lemur Center, his nearly 70-year career took him around the world, studying species as disparate as fish in Belize, giant tortoises in Aldabra, songbirds in England and antelopes in Israel.

His studies on early mother-infant bonding began during his Ph.D. at Yale, focusing on ducks and waterfowl. A nudge from a professor led him toward goats, a species Klopfer loved since childhood. “They're personable. They're very social. They're like dogs in many ways,” he said in a 2022 interview.

Goats offered an additional financial advantage. “Yale was already supporting my waterfowl research. They weren't about to pay for an even more expensive animal, like a goat. But Martha and I figured that the goats would pay for themselves, as they did. From the first year we were married, we had goats, who provided us with milk, and cheese and butter, and so forth, so it was a practical choice, as well as a scientifically appropriate one,” he said. 

Whereas waterfowl chicks were known to attach themselves to the first moving creature they saw upon hatching (not necessarily their mother) in a process known as “imprinting,” goats exhibited “bonding,” a process driven by the mother. Klopfer discovered that if mothers were separated from or even just prevented from smelling their newborns for a mere 15 minutes, they would later show no interest in them, effectively abandoning their offspring. In these vital first minutes, the release of oxytocin facilitated mother-offspring attachment, a process crucial for survival in many species.

After a year of postdoctoral studies in Cambridge, Klopfer joined Duke in 1958. “I was able to get a tract of forest set aside for what became the Duke Field Station for Animal Behavior Studies — which then 40 years later mutated into the Duke Lemur Center — so I was able to have a herd of 40 goats.”

Klopfer arrived in Durham as a new Duke professor with accomplished credentials as an activist, driven largely by his Quaker faith and pacifist beliefs. 

He was expelled from UCLA after his freshman year because of his participation in a campaign to end mandatory military training for students through ROTC. He would return to continue his degree, and as an undergraduate was sentenced to three years in prison for refusing to participate in the draft for the Korean War, though he received probation after a short time of incarceration. 

Klopfer later said the attention his activities drew from the Joseph McCarthy-led House Un-American Activities Committee drove him to pursue postdoctoral work abroad in Cambridge.

When he was courted by Duke to return to the U.S., the proximity between campus and his promised field station was a big draw. He was offered a three-year contract, and when he and Martha left “cosmopolitan Cambridge” and came to “provincial Durham,” they had no expectation to remain here long.

His first exposure to the American South was a shock. From the moment they arrived at the airport, “passing through the building and suddenly seeing double sets of drinking fountains — 'Colored Only,' 'White Only' — and double sets of bathrooms. We’d never in our lives experienced anything like this,” he said in a 2003 interview with the Durham Civil Rights Heritage Project.

This was four years after the landmark Brown v. Board of Education of Topeka ruling in 1954, which upended the “separate but equal” doctrine used to justify segregated schools. He arrived in Durham to find a state that was legally bound by the Brown decision but, like others in the South, was only slowly creeping toward integrating schools and public accommodations. 

Not content to wait for the integration of local public schools nor willing to subject his children to segregation, in 1962 the Klopfers joined with fellow Quakers — or Friends, as members of the Society of Friends are known — from the Quaker Meeting Houses in Durham and Chapel Hill to launch the Carolina Friends School, one of the first racially integrated schools in the South and the first in the state. 

“The only alternative seemed to be founding a community here which would not perpetuate racial myths and segregation,” Klopfer is quoted as saying on the school’s website. “The formation of a school open to children of all races and founded on Friends’ principles, it was quickly agreed [by a group of Chapel Hill and Durham Friends], would be the most useful step we could take. We took it, and it was.”

Not just co-founders, the Klopfers also donated the land that would become the school’s main campus. The school would be bolstered by other state and higher education leaders including former Gov. Terry Sanford, who would serve as president of Duke from 1970 until 1985, and Bill Friday, who was president of the UNC system from 1956 until 1986.

Klopfer’s dedication to civil rights would later earn him a place in the annals of Supreme Court history as the plaintiff and victor in a case that would ensure defendants in state court proceedings have a right to a speedy trial. On January 3, 1964, Klopfer was joined by a small number of Duke and UNC faculty and students for a visit at the Watts Restaurant and Grill in Chapel Hill, to protest the establishment’s segregationist stance. The group was arrested, then indicted by a grand jury for criminal trespassing.

“But we never got inside, because they apparently had been tipped off about our coming. We were jumped on in the parking lot and beaten bloody,” he said in the 2003 interview.

The circumstances of his arrest were typical of the sit-in movement, but while the other trials quickly ended in convictions, Klopfer kept getting a hung jury. Prosecutors continued to pursue the charges but did not call the case, leaving Klopfer in legal limbo, having to appear in court daily with no sense of when his case might be retried.

Klopfer’s appeal would make it to the U.S. Supreme Court, which in 1967 ruled that the right to a speedy trial extended to state courts as well as federal courts. “That turned out to have an enormous impact on cases, thousands of cases around the country where the defendants were being held for long periods of time, and the prosecutors weren’t sure enough with their evidence to be able to convict them, but by holding them indefinitely, could get them to plead to lesser charges,” Klopfer said in 2003.

Klopfer’s mounting legal fees ended up being the unlikely catalyst for a new research collaboration. “My friends and colleagues set up a defense fund, and they contacted my former teachers and friends at Yale for contributions,” he said in a 2020 interview.

Among the contributors was then Yale professor John Buettner-Janusch, with whom Klopfer later met. “I was studying the neuroendocrine aspects of mother-infant relations in goats, when John Buettner-Janusch persuaded me that lemurs would serve better. In exchange for space at the Zoology Department's Behavior Station, which I directed, he offered to move his lemur colony from Yale and share it with me.”

In 1965, Buettner-Janusch joined Duke, bringing with him approximately 200 primates. In 1966, the Duke Primate Center was born, and would later become the Duke Lemur Center, the world’s largest and most diverse collection of lemurs outside of Madagascar.

In later years, Klopfer’s research expanded into the molecular, physiological and neurological underpinnings of sleep and hibernation, which were the focus of his last research paper, in 2025. The topic generated great interest due to its parallels to human aging — and our desire to postpone it.

"In 2006, when I first assumed the Lemur Center’s directorship, Peter invited me to his office for a seemingly impromptu meeting. It immediately became clear to me that the real agenda was to test the waters regarding any interest I might have in primate hibernation and what support I might lend that research at the Center. I was absolutely all in, and so began what has now been a 20-year collaboration and deep friendship," Yoder said.

Klopfer’s approach to teaching was at times visionary. In 1974, he had a disagreement with the Duke Undergraduate Faculty Council over his grading practices in an Introduction to Biology course. In it, Klopfer offered students four different methods through which they could demonstrate proficiency in the course. If students couldn't achieve a grade "A" in their chosen method, rather than failing them Klopfer simply didn't record their grade, and allowed them to try one of the other options. 

His pedagogy left a mark on the field of animal behavior. Professor Emeritus of Biology Steve Nowicki remembers using Klopfer’s book “An Introduction to Animal Behavior: Ethology’s First Century” as an undergraduate in the 1970s. “Many years later, I came to realize that Peter’s book deeply influenced my own approach to teaching science, emphasizing how we know something, not just what we know. It also played a big role in my decision to go on to do graduate work in organismal biology,” Nowicki recalled.

He mentored 44 Ph.D. students over his career, but his impact extended beyond those he officially advised. “In the 1990s, Peter would often host grad students and faculty interested in animal behavior and behavioral ecology from across the Triangle for joint journal club meetings at his farm,” remembers Nowicki. “Those were good times, made even better by the fact that Peter would always provide a few bottles of some interesting wine and offer a short wine tutorial as part of the meeting.”

His mentorship extended to colleagues as well. “When one of my daughters wanted to learn more about his court case from the 1960s, Peter met with her several times to share his story and help connect her with historians and scholars who aided her in her documentary. He was patient, supportive and responsive to her many requests for additional details and clarification,” said Dye. “His generosity with his time was extended to others at the Lemur Center over the years I knew him. And I always knew that if I ever needed his help, all I had to do was ask.” 

Despite retiring in 2006, Klopfer continued teaching until the COVID pandemic, in 2020. “I decided I wasn’t psychologically equipped to teach on Zoom,” he said in 2022.

"Peter was a fixture of our department for more than six decades. He had wonderful stories to tell about his science and cared deeply about both education and conservation. I valued his advice and mentorship as a new chair at a time of considerable social upheaval in 2020-2021. He will be missed and remembered fondly," said Emily Bernhardt, James B. Duke Distinguished Professor of Biology and department chair. 

“I am so grateful for the way Peter shaped the department that I joined 28 years ago, and how that influence has persisted over the years in positive ways,” said Susan Alberts, Robert F. Durden Distinguished Professor of Biology. “I'm also grateful for who Peter was in the world, as an actor who promoted justice and fairness.”

Klopfer was also an incredible athlete and an avid runner. He once credited his desire to become a better runner to nearly being trampled to death by a charging 3,000-pound bull elephant seal.

Duke’s legendary head track coach Al Buehler (who later became coach for the U.S. track team in the 1972 Olympics) introduced Klopfer to cross-country running, and from then he was hooked. Klopfer coached Duke’s women’s track club in the 70s, prior to it becoming a team, and was still running marathons until his mid-eighties. 

"I got to know Peter as a running buddy and coach in my first few years as a junior faculty member,” said Professor of Biology Amy Schmid. “He was many decades my senior but challenged me to run my best. His energy, enthusiasm, and encouragement were amazing. I will miss Peter but know that his legacy of inclusion and fighting for equity will live well into the future."

Not a fan of driving, for years Klopfer covered the roughly 6-mile commute between home and work by running or cycling. At nearly 90, when his diminishing balance restricted his ability to ride a bicycle, he still cycled 20-25 miles on weekends with friends on a semi-recumbent e-tricycle.

His advancing age also failed to stop his civil activism. In 2013, at 82 years old, Klopfer was briefly jailed in a Moral Monday peaceful protest against legislation recently passed by the N.C. General Assembly. 

In his 2003 interview, Klopfer said that during times when he was frightened about the state of American democracy or concerned about governmental overreach, he would return to his 1966 experience taking in the arguments in his case before the Supreme Court justices. 

“I think back on that, and I think, well, there’s still hope,” he said.