Not one but two specimens of the world’s rarest known species of whale have been discovered on a New Zealand beach, according to a report published Monday in the journal Current Biology. The species, called the spade-toothed beaked whale, is so rare that before the find researchers weren't even sure if it still existed. The two whales washed up on Opape Beach in New Zealand’s Bay of Plenty. At first scientists thought they were examples of a much more pedestrian species, the Gray’s beaked whales, which are the most commonly beached whales in the region. But after undertaking a DNA...