It looks more like a worn sock than a fearsome predator. It moves slower than an escalator. By most accounts, it is a clumsy and near-sightless relic drifting in the twilight waters of the Arctic, lazily searching for food scraps.

But the Greenland shark, an animal one researcher (lovingly) said, “looks like it’s already dead”, is also one of the least understood, biologically enigmatic species on the planet.

But this month, scientists made a groundbreaking discovery: the sharks are not, in fact, blind. The newly published findings upend commonly held beliefs and expose the challenges of studying a shark that has long resisted the reaches of science. But the disruptive nature of the research also underscores the challenges scientists face in predicting how a rapidly changing climate might harm or help the elusive fish.