But now, the two are about to be reunited at the Smithsonian National Museum of Natural History, in Washington.
Otago palaeontologist Emeritus Prof Daphne Lee said a fossilised fragment of the whale’s skull and a chunk of its jaw containing an ‘‘unusual tooth’’ was discovered and collected by an American researcher on Seymour Island, off the coast of the Antarctic Peninsula, in the 1970s.
Prof Lee said when her colleague, the late Emeritus Prof Ewan Fordyce, found out about the discovery, he went to the island to see if he could find the rest of the fossilised whale.
During a 1987 expedition, he and a science team discovered the other 95% of the fossil embedded in rock.
‘‘One of Ewan's areas of expertise was seeing a little bit of a fossil vertebrate somewhere like North Otago, or in this case, Antarctica, and working out where the rest of it must be that was hidden from view.
‘‘Amazingly, given the weather conditions down there, he was actually able to locate where the rest of the whale was and with a huge amount of effort and involvement from other people, they managed to excavate it in large blocks, crate it up and it was brought back to New Zealand.’’
He spent the rest of his life preparing and studying the specimen.
It took him and his research assistants decades to painstakingly expose the fossilised bones, she said.
‘‘Ewan said it was like digging an eggshell out of a block of concrete.
‘‘I thought that was a great way of putting it.’’
It was not until 2018 that Prof Fordyce and PhD student Felix Marx published a paper on their findings and described the fossil as a 34-million-year-old, 8m-long, sharp-toothed, Llanocetus denticrenatus — a distant ancestor of today’s baleen whales, like the humpback, blue and minke whale.
In the paper, Prof Fordyce expressed his hope that the fossil would be reunited with the skull and jaw fragments at the Smithsonian.
He wanted it to go there, rather than the skull and jaw come here, because the fossil was found in the South American part of Antarctica, Prof Lee said.
‘‘It was not appropriate for it to be in New Zealand.
‘‘If it had come from the New Zealand area of Antarctica that we look after, that would have been a different matter.’’
Now, the 1930kg fossil is on its way to the United States.
Some of the fossil fragments were so large and heavy, it took several people to lift each block and windows had to be removed in the basement of the geology building to get them out, she said.
They were expected to arrive in Washington early next month.
Smithsonian National Museum of Natural History lead curator Nicholas Peynson, a former student of Prof Fordyce, played a major part in reuniting the two parts of the fossil.
‘‘I’m closing a lot of circles.
‘‘I’m reuniting this specimen with its jaw fragment in a collection I oversee and I’m following through on a promise I made to a mentor.
‘‘It’s been a group effort from both sides of the Pacific and if it helps inspire the next generation, that’s the best possible outcome.’’
