Robert Peck has escaped headhunters in the Ecuadoran forest, discovered three species of frog, and documented the lives of nomads on the steppes of Mongolia.

Most recently, the Academy of Natural Sciences naturalist, curator, and chronicler helped unearth evidence of the long-lost first published drawing by John James Audubon.

The academy made the announcement Thursday, and it was heralded as a vital piece of an enduring Audubon mystery.

For those who know Peck, who spent 10 years on the trail of the drawing, it was hardly surprising. Just another stellar moment for a fearless explorer, passionate naturalist, and world-class scholar.

"I know for a fact that there is no other research institution or museum anywhere in the world who has someone like Bob on their staff," said Keith Thomson, a former president of the academy.

Many people aspire to master a plethora of subjects, but few succeed. Thomson thinks of Peck as "a throwback to another age of natural history, when you could be an artist, an explorer, in his case a photographer, a writer, a gardener."

In the academy library, "Bob is likely to appear with some visitor in tow, expounding earnestly on Abe Lincoln's hair" - part of the academy's collection of presidential locks - "or Charles Willson Peale's portraits," Thomson says.

If Peck's full mustache and beard make him look like some of the 19th century explorers he reveres, that's not quite the intent.

True, he regards the period as a golden age of natural history. Before that, voyagers like the British explorer James Cook were still getting the broad overview of the world. By the 19th century, "they were getting down and dirty into the details of flora and fauna," Peck says with delight.

Back to the beard. Peck grew it during a 1978 hiking trip through the Southeast to follow the trail of the Philadelphia naturalist William Bartram.

The reason he's kept it all these years, even as it changed from dark brown to mostly white, is that it saves him time.

Five minutes a morning over several years adds up to another article he can publish, another book he can write.

At 57, Robert McCracken Peck still lives in the Chestnut Hill home where he grew up. His three young children are budding naturalists who often beg to come to work with him.

He still has some of the shells and birds' nests he collected as a kid. And, yes, he read National Geographic and fantasized about going to many of those places himself some day.

On a family trip to Williamsburg, Va., he became "besotted by this concept of living history." He still has a wooden shoe peg a cobbler there gave to him. He views these things not as trophies, but as "a window into a part of life."

Later - after studying art history and archaeology at Princeton University, then getting a master's degree in American cultural history through a University of Delaware Program at Winterthur - he knew he wanted to work in a museum.

He loved museums. "I was kind of an academy brat," he said.

So in 1976, on the advice of longtime academy researcher Ruth Patrick, also a family friend, he applied and, to his astonishment, was offered a job as assistant to the director.

He's held many positions since. "I couldn't believe it was actually considered work," he said. "Here at the academy, we're all kids at heart, finding out about nature."

One of his first tasks - and something he continues to this day - is fielding calls from people who have found something odd. Even if the person is sure the footprint is from Bigfoot, "what I love about those calls is, they're so full of curiosity and optimism," he said. "They think it's important, and it is important."

Soon, however, he began traveling with academy scientists to document their work.

"It's somewhat of a lost art, this chronicling of scientific expeditions and science in general," said paleontologist Edward Daeschler, the academy's acting president. "But if it's a lost art, it's not lost on Bob. He's right there with the greatest of them today."

Frank Gill, a former academy researcher who is interim president of the National Audubon Society, recalls that in addition to being a splendid photographer, Peck often filled the role of diplomat on the many expeditions they shared.

"He can charm just anybody in the world with a twinkle in his eyes. You get to a remote village and the kids love him, and he just kind of melts right in, in a playful, engaging way. I've seen that in different parts of the world. It's his style. People are comfortable with him."

But he also often adds to the science. On a 1984 trip to Ecuador - the one when he was confronted by headhunters - he deterred them by claiming he had a contagious and deadly disease. He also discovered three species of frog, one of which was later named for him - Eleutherodactylus pecki.

The trips were often treks to remote areas, and Peck once joked he'd been bitten by about every creature possible.

Indeed, in 2006, when the White House sent him back to Mongolia - one of six visits so far - for its 800th birthday celebration, he was almost disoriented at being whisked around in fancy limousines. He was more accustomed to walking or going on horseback.

Other than in the field, perhaps the only place Peck would rather be is deep inside the academy, in his paper-strewn office, with arched windows overlooking 19th Street.

The old bookshelves are full of volumes, and mementos include a silver prayer wheel from Mongolia, a woven tribal basket from Venezuela, and a little box of gravel from Greenland, collected by Robert Peary on his 1891 Arctic expedition, which the academy funded.

"I love objects and the stories they tell," he says, and, after a pause, elaborates. "What they tell us about ourselves."

The office is up a brief flight of stairs from the library, with its portraits of somber Victorian academy notables.

And, behind two more locked doors, the archives, which he oversees. The academy has 17 million biologic specimens, but here its treasures include John Bartram's pocket watch, an embroidered buckskin jacket that Audubon wore on an 1843 expedition, and Ruth Patrick's pith helmet.

"Here's another interesting story," he says, all but jumping across a humidity-controlled room to a wooden globe from 1825, built in a misguided attempt to show that the Earth was hollow.

One of his four books - the 1990 Land of the Eagle: A Natural History of North America - was a companion to a BBC-PBS series with David Attenborough and was on the bestseller list in Britain for weeks.

Another former academy president, William Y. Brown, now at the Woods Hole Research Center in Massachusetts, praised Peck's "commitment and passion for the arcane that few people have. He's definitely an important fixture of the firmament of everyone who cares about natural history, and among the many treasures of the Academy of Natural Sciences."

For now, Peck, whose current title is curator of art and artifacts and senior fellow, is planning a 2012 Harvard University exhibition of the natural history drawings of British poet Edward Lear.

But most of the books and papers in the extra office he has commandeered relate to his book chronicling the 200-year history of the academy for its bicentennial in 2012. He describes his immersion in the varied cast of characters - from Ernest Hemingway and Edgar Allan Poe to Lewis and Clark - as "fascinating, fantastic stuff!"

Contact staff writer Sandy Bauers at 215-854-5147 or