East is East and West is West and never the twain will meet -- at least as far as the world's freshwater eels are concerned, Reuters reported. It has long been established that the freshwater eels of the United States and Europe originate in the Sargasso Sea off Bermuda. But the origin of their eastern cousins, the Japanese freshwater eels, has remained a mystery -- until now. Writing in the science journal Nature, researchers from Tokyo University's Ocean Research Institute say they have solved the puzzle. "We have proposed that the Japanese eel spawns near seamounts west of the Mariana Islands close to the time of the new moon," they wrote. "We are now able to corroborate this location and timing." The islands are in the western Pacific, about three-quarters of the way from Hawaii to the Philippines, south of Japan. They form a commonwealth in political union with the United States.