This is a story about the discovery of an organ that measures twelve feet long and four inches wide. You might well assume that this is old news. After all, how could something the size of a lamppost go unnoticed by anatomists? And yet, in fact, it’s only just come to light.

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