La Jornada: Whale cemetery found in the Indian Ocean

New York. Scientists have discovered communities of marine life, including jellyfish, tube worms and ophiuras, thriving in a million-year-old whale graveyard.

These cemeteries are formed when whale carcasses fall to the seafloor, becoming food for nearby creatures. This one, located at a depth of up to seven kilometers in the southeastern Indian Ocean, covers the largest area and is, to date, the deepest and oldest found.

The enormous size of whales and the unique chemistry of their bones are the keys to the formation of these unique underwater habitats, said Xikun Song, a biologist at the Institute of Deep Sea Science and Engineering of the Chinese Academy of Sciences.

“At the same time, the very nature of the deep ocean makes these deposits exceptionally difficult for scientists to locate,” wrote Song, who was involved in the recent discovery.

In 2023, researchers explored the remains during several underwater expeditions, collecting samples and mapping the extent of the necropolis. They found five sites of carcasses and fossils, including the skulls of beaked and baleen whales. The oldest bones date back to 5.3 million years ago.

Living on the corpses were countless creatures, large and small, including sea cucumbers, dwarf lobsters, and clams. Many of them are probably species never before documented, according to findings published in the journal Nature.

“The potential number of specimens is simply staggering,” said paleontologist Stephen Godfrey of the Calvert Marine Museum in Maryland, who was not involved in the research.

According to the study authors, it is likely that many factors combined to preserve the bones for millions of years. Their density was sufficient to resist attacks by bone-eating worms, and their location deep enough in the ocean prevented them from being buried by dust and loose particles. Additionally, the bones were coated by a thin layer of minerals from the surrounding seawater, which may have prevented their degradation.

Why did so many whales die here? Perhaps they already lived in the area and died of natural causes. Some may have perished from exhaustion or illnesses resulting from deep-sea diving. The V-like shape of the terrain could also have funneled the remains toward their resting place, the authors wrote.

These discoveries are important because they allow scientists to learn about the vibrant communities that find a way to thrive even in remote and difficult-to-access environments.

The study of whale graveyards “is important to understand how life can adapt to such extreme conditions, not only due to the lack of light and oxygen, but also the incredibly high pressure,” Giovanni Bianucci, study co-author and paleontologist at the University of Pisa in Italy, said in an email.