Scientists discover huge deep-sea "whale graveyard" in Indian Ocean, dating back 5.3 million years

Scientists have discovered a huge "whale cemetery" in the deep sea of ​​the southeastern Indian Ocean. It is about 1,200 kilometers long and is located in the Diamantina Fracture Zone (Diamantina Fracture Zone) about 7 kilometers below the sea surface. The research team pointed out that this is the largest, deepest and oldest whale cemetery currently known, with some remains dating back to 5.3 million years ago.

According to foreign media reports, whale graveyards are special ecosystems formed after whale carcasses sink to the bottom of the sea. Huge whale carcasses will become an important food source for deep-sea creatures, and bones and organic matter can also nourish surrounding creatures for a long time. This underwater cemetery was discovered by a research team from China, Italy and New Zealand, and a related paper has been published in the journal Nature.

Researchers boarded deep-sea submersibles for multiple explorations in 2023. During 32 dives, they collected samples from 485 whale fossil sites and active whale colonies, and found 5 carcass sites and a large number of fossils, including the fossil skull of the 5.3 million-year-old beaked whale Pterocetus benguelae, and an Antarctic minke whale carcass about 5 meters long, which is currently the largest whale carcass found in the area.

The study points out that these whale bones can be preserved for millions of years. Possible reasons include the high density of whale bones, which is strong enough to resist the erosion of bone-eating worms, and the fact that the remains are located in the deep sea and are not easily buried by dust and loose sediment. In addition, the surface of the bones is covered with a layer of minerals formed by seawater, which may also slow down the rate of deterioration. As for the large number of whale carcasses in the same area, researchers speculate that they may have lived nearby and died of natural causes, or they may have died from exhaustion or disease caused by deep-sea diving. The seabed area is shaped like a letter V, and the remains may also be gathered in the same place.

Study co-author Giovanni Bianucci, a paleontologist at the University of Pisa in Italy, also pointed out that studying whale graveyards "is very important to understand how life adapted to such extreme conditions, not only because of the lack of light and oxygen, but also because of the incredibly high pressure."