Mr. Howes was, however, the curator-director at the Bruce Museum in Greenwich, Conn., and even if he could not attend the dinner, he wanted to exhibit some of it at the museum. So Wendell Phillips Dodge, a theater impresario who had organized the dinner, sent Mr. Howes a sample, which he labeled Megatherium.

Image Wendell Phillips Dodge organized the 1951 Explorers Club dinner. Credit... Explorers Club Research Collections

That sample found its way to the Peabody in 2001, prompting years of puzzlement among students and professors. Was this jar of ethanol with a bit of flesh really cooked, extinct ground sloth from Alaska?

Recently, Matt Davis, a graduate student at Yale studying ice age ecology and one of the authors of the new paper, was having lunch with Eric Sargis, another author, who was giving a course in mammalogy. Mr. Davis was a teaching assistant for the course, and at the lunch, Dr. Sargis lamented, “It’s amazing that I can’t get anybody interested in the piece of sloth meat we have.”

Mr. Davis recalled, “I was immediately hooked.”

DNA analysis was called for, and they recruited Jessica R. Glass, another graduate student, and the first author on the paper, whose day job is studying the genetics of marine fish. As an undergraduate at Yale, she said, “I always knew about this specimen,” adding, “I was fascinated by it.”

She and other scientists joined the team. They assumed the flesh was thousands of years old, which meant that testing for DNA was more complicated than testing a more recent bit of flesh. “Also,” she said, “the meat was cooked.”

There was some legitimate science to be done. If the meat was really Megatherium, that would extend the species’ known range from South America all the way to the Aleutian Islands in Alaska.