The old bacteria were breathing long before the oxygen would be abundant

Today, oxygen compensates around 21 % of JonaBut it was not always very abundant. About 2.7 billion years ago, blue bacteria – upcoming bacteria that generate energy through optical representation – have evolved and began to release oxygen in the oceans. This gradually accumulated oxygen in the atmosphere in a process called Great oxidation event (Goe), which happened between 2.4 and 2.1 billion years. However, new research indicates that the air -based bacteria (oxygen) has appeared long before GOE.

An international team of researchers rebuilt the evolutionary tree for one of the first forms of the Earth, and revealed that bacteria may have adapted to the presence of oxygen long before they are abundant in Jonah. Their work, detailed in a Ticket It was published today in the Science magazine, challenging the previous assumption that most of life before Goe was anaerobic, that is, living organisms that do not need to survive.

The researchers used a multidisciplinary approach to rebuild and track an evolutionary tree for bacteria when adapted to oxygen. This included the analysis of geological records, fossil evidence, and more than 1,000 various bacterial generators; Submission Evolutionary reconciliation (Comparing the history of two lifestyles closely intertwined); And computer modeling. According to their evolutionary tree, the predecessor of the last joint bacteria will be between 4.4 and 3.9 billion years.

“This joint approach to the use of genetic data, excavations, and geodic history of the Earth, brings a new clarity to the evolutionary timelines, especially for microbial groups that do not have a fossil record,” said Jerley Solusi, a participant in the study and evolutionary biology from the Okinawa Institute of Science and Technology, at a university. statement.

Their results indicate that some air bacteria appeared before GOE, about 3.22 to 3.25 billion years. It is possible that these bacterial genealogies were the ancestors of blue bacteria, which means that they have evolved the ability to metabolize small amounts of oxygen before developing optical representation. In fact, the research indicates that the adaptation of oxygen has played an important role in the development of optical representation capabilities of blue bacteria – and as a result, the changes in the Earth’s atmosphere during GoE.

Tom Williams, the organizing biologist from the University of Bristol and participated in the study, said that the team’s approach “works well to study the spread of antennas and may also be a useful approach to exploring how other features appear and interact with the volatile environment of the planet.”

The study is also a reminder of the fact that the atmosphere we enjoy today has been formed with billions of years of microbial activity.