Carl Zimmer in his excellent blog, The Loom:
The discovery emerged out of a blood-drenched confusion. Alexander Werth, an anatomist, was standing on an ice sheet miles off the coast of Alaska’s North Slope. He was watching Inupiat whale hunters dismember bowhead whales they had caught in the Bering Sea. This government-sanctioned hunt is one of the best opportunities for whale anatomists to get hold of fresh tissue from the animals.
To take apart the head of a whale, the hunters would slice off the lower jaws and the tongue, which could be as big as a minivan. They would then climb onto the roof of the whale’s mouth and cut away the baleen–the hair-like growths that the whale used in life to filter small animals from the water. On the roof of the mouths of bowhead whales, Werth and his colleagues noticed something strange: a peculiar rod-like organ stretching down the midline of the palate.
It had never been described in the bowhead before. What made the organ particularly peculiar was that, as the Inupiat cut the whales apart, it poured forth huge amounts of blood. Why, the scientists wondered, should a bowhead whale have an organ in the roof of their mouth? And why should it be so bloody?
More here.