Deepest and most extensive whale graveyard discovered in Indian Ocean

The largest carcass discovered was a five-metre long skeleton of an Antarctic minke whale. Photograph: Gerard Soury/Getty Images

The oldest, deepest and most extensive whale graveyard yet discovered has been found in the south-eastern Indian Ocean, with fossils dating back more than 5m years.

Whale falls – the term for dead whales that sink to the ocean floor – are not uncommon, but most have been found at depths of less than 4km (2.5 miles). By contrast, the newly discovered necropolis reaches depths of more than 7km, and extends hundreds of miles across the sea floor.