Whales that end up on the beach make headlines. But those that sink to the bottom of the ocean make new homes for sea life. The brawn, blubber, and bone of these unlucky cetaceans—some 70,000 of which perish during harrowing seasonal migrations each year—nourish a vibrant, constantly evolving community of creatures. Opportunistic eaters can flourish on a decaying corpse for anywhere from a decade to a century. Marine biologists have discovered dozens of new critters in these deep-sea ecosystems since they first encountered one in 1987. For animals at the bottom of the ocean, a whale fall is a meal ticket. But for the humans above, it’s a helpful reminder that, even in the modern era, most underwater mysteries remain unsolved. This timeline tracks what little we know about a gray whale’s decomposition, and the friends it makes along the way.