When a great whale dies at sea, it usually sinks. Down past the sunlit water, down past where light runs out, sometimes thousands of metres, until it settles on the cold, dark sea floor.

The deep sea is mostly a desert. Food arrives as a slow drizzle of "marine snow" — flakes of dead plankton and waste drifting down from above. Then, suddenly, tens of tonnes of meat, fat and bone land in one place.

Scientists call it a whale fall. For the creatures nearby, it's a banquet that lasts for years.

Stage one: the scavengers

Within days, the scavengers arrive. Hagfish — eel-like creatures that produce astonishing amounts of slime — burrow into the flesh. Sleeper sharks, crabs and amphipods tear at it. Over months, they can strip away most of the soft tissue.

Stage two: the colonisers

Next come smaller animals — worms, snails and crustaceans — which feed on the remaining scraps and on the nutrient-rich sediment around the bones.

Stage three: the bone-eaters

Now the strangest part. The skeleton is still packed with fats and oils. Bacteria break these down, producing chemicals that support whole communities of other microbes and animals — similar to the life around deep-sea hydrothermal vents.