TOKYO - Researchers say a museum in central Japan has right whale fossils that are at least 5 million years old, making them the oldest fossilized remains of the animal in the world, officials said Wednesday.
Researchers working in Nagano prefecture (state) estimate the fossilized skull bones and jaw of a right whale on display at the Shinshushinmachi Fossil Museum to be 5 million to 6 million years old, said museum curator Ken Narita.
The oldest right whale fossil previously found was a skeleton that was uncovered in Italy that dates back about 4 million years, Narita said.
"This was an amazing find, and to have found the oldest one of this type makes it truly remarkable," he said.
The skeleton was first discovered in 1938, when residents found the whale's spine and rib bones exposed on the ground. However, the skeleton was left undisturbed because the country was then at war, according to the museum's Web site.
Researchers finally returned to the site in 1967, but the exposed parts of the skeleton had been scattered or lost. Only the skull and upper jaw parts were left to be excavated, but it was not until recently that the museum could afford to get the bones dated, Narita said.
While of the right whale genus, the animal's species is believed to have been different from those of other right whale fossils found so far, he added.
Right whale skeletons have often been found in Europe, but the Nagano fossils and their dating "raises the possibility that right whales might have originated in the North Pacific," said Toshiyuki Kimura, curator of the Gunma Museum of Natural History. Kimura also took part in the fossil research.
Right whales are now designated an endangered species and banned for hunting by the International Whaling Commission. The entire North Atlantic right whale population is estimated at just 350, according to a U.S. federal researcher.
Nagano is 180 kilometers (110 miles) northwest of Tokyo.