Strange creatures wake up after more than 100 million years of sleeping on the ocean floor

Microorganisms were buried in the dust 101.5 million years ago, before Tyrannosaurus appeared on this planet. As time went on, continents shifted, oceans rose and fell, great apes appeared, and eventually humanity evolved with the curiosity and skill of digging through those ancient cells. In 2020, Japanese researchers brought single-celled organisms back to life.

Researchers aboard the drilling rig JOIDES Resolution collected samples of sediment from the ocean floor 10 years ago. The samples were taken from a depth of 100m below the 6,000m deep bottom in the South Pacific Ocean. It is an area with very few nutrients and oxygen reserves for organisms to survive. In this study, the scientists wanted to look for data on how microorganisms can survive in such a remote and inhospitable region.

These cells were found to have the ability to wake up in the presence of oxygen and nutrients.

"Our main question is whether life can survive in a nutrient-restricted environment or is this an uninhabited area," said scientist Yuki Morono from the Marine Science and Technology Agency. -Earth Japan said. "We also want to know how long microorganisms can sustain life in the near absence of food."

The results of the study show that cells found in sediment samples 101.5 million years ago have the ability to wake up in the presence of oxygen and nutrients. "I was skeptical at first, but then we discovered that up to 99.1% of bacteria in the sediment deposited 101.5 million years ago were still alive and ready to eat."

The bacteria have stopped all noticeable activity, but when it comes to nutrition and other vital needs, they become active again. To ensure the samples were not contaminated with modern microorganisms, the team opened the sediment in a highly sterile environment, selecting the microbial cells present and delivering nutrients to them through a small tube so as not to be contaminated with modern microorganisms.

The cells responded very quickly. They gobble up nitrogen and carbon. Within 68 days, the total number of cells had increased fourfold from the original 6,986 cells.

Aerobic (oxygen-breathing) bacteria are the strongest cells and they are most likely to wake up. These tiny creatures have survived thanks to tiny air bubbles that settle with sediment over geological periods. It seems that the metabolic rate of aerobic bacteria is very slow, enough for them to survive for such a long time.

The study was published in the journal Nature Communications on June 28, 2020.