An African bull elephant greets visitors in the rotunda of the National Museum of Natural History. (Smithsonian Institution)

Kristofer Helgen, a highly regarded mammalogist and curator at the National Museum of Natural History, has left the Smithsonian in the wake of a bitter, months-long conflict with administrators.

Helgen, 36, had been accused of research misconduct during a high-profile collecting expedition in Kenya. He was cleared after an investigation that Helgen and some of his colleagues say was an attempt to bully and discredit him.

The Smithsonian Institution declined to comment on the circumstances of Helgen's departure, citing a policy against commenting on personnel matters.

When he handed in his resignation Thursday, Helgen said that his department chair, John Coddington, told him, “Now give me your underwear” — a remark that Helgen said did not seem like a joke.

To me it was just an unbelievable moment of indignity after 15 months of anguish over complaints that were just really hard to understand in the first place,” Helgen said. 

Coddington did not respond to a request for comment on the allegation.

Helgen became curator of the mammals collection at the museum when he was just 28 and is considered a rising star in the world of zoology. In 2013, he was the lead researcher on the celebrated discovery of a new raccoon species called olinguito — the first carnivorous mammal to be discovered in the Americas in a generation. He also drew coverage for his 2015 expedition to Kenya, which was modeled on a similar trip taken by Theodore Roosevelt for the museum more than a century ago. Just this week, he was part of a team that announced the discovery of a new primate species they call the Skywalker hoolock gibbon.

According to Helgen and some of his colleagues, who spoke on the condition of anonymity because they feared losing their jobs, the media attention, paired with Helgen's unorthodox way of doing things, meant Helgen ran afoul of museum administrators and some other colleagues. Many at the institution seem to have been rankled by behavior they saw as brash or unscientific, such as reorganizing the mammal division, bringing in many more students and interns, and pushing to get more news coverage, they said.

The investigation into Helgen's trip was first reported by writer Michael Balter in the Verge in August. Staffers had alleged that, during the 2015 trip to Kenya, Helgen attempted to take specimens out of the country without a proper permit. An initial inquiry by the Smithsonian's inspector general found evidence of confusion about the handling of specimens but concluded that no laws or Smithsonian rules had been broken. Then the museum opened its own investigation, which went on for 10 months. Based on interviews with Helgen's co-leaders on the Kenya trip, the Verge alleged that the inquiry ignored evidence that could have exonerated Helgen.

“It was a witch hunt,” one researcher, speaking anonymously out of concern for his job, told The Washington Post. “How else do you characterize going after someone who was cleared of criminal charges? The only thing that comes to mind is a witch hunt out of jealousy . . . It looks like the whole arc was 'I'm going to teach you a lesson.'”

In the end, Kirk Johnson, director of the National Museum of Natural History, found Helgen partially responsible for some of the accusations and ruled that he be suspended without pay for two weeks. When Helgen returned, he wasn't allowed back into his office and had to get permission from a collections manager to access the collection for which he was curator.

“It really is the way I was treated on my return that made me think it was going to be a better idea to move on to a position elsewhere,” Helgen said. “Even when I thought this was behind me, I was isolated in the section of the museum away from my duties and collection.”

During the investigation, many top scientists, including writer Jared Diamond, Australian mammalogist Tim Flannery, and Harvard evolutionary biologist and National Museum of Natural History board member Scott Edwards, sent letters in support of Helgen to museum officials. Nearly three dozen of Helgen's current and former students also submitted a letter urging the museum to hold on to the curator.

Helgen continued to contest Johnson's ruling, and in December, the museum reversed the decision, clearing Helgen's disciplinary record.

Around the same time, the mammalogist was offered a tenured position as professor of biological sciences at the University of Adelaide, his alma mater. He will move to Australia with his wife, Lauren Helgen, a fellow National Museum of Natural History mammalogist, and their young son.

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