Scientists at the University of Colorado at Boulder have discovered that single-celled organisms living in modern oceans may have much in common with life forms that existed billions of years ago.
The authors of the work studied the microbes of cyanobacteria. These single-celled photosynthetic organisms are also known as blue-green algae. Today they can be found in almost any large body of water. But more than 2 billion years ago, they played an important role in the history of the Earth’s development. During the period known as the “Great Oxygenation Event,” ancient cyanobacteria produced a sudden and sharp oxygen release.
Scientists today still don’t know what these microbes looked like, where they lived and what caused the release.
The authors of the study decided to investigate natural and genetically engineered cyanobacteria. These ancient microbes may have swam freely in the open ocean and were similar to a modern life form called beta cyanobacteria.
This research gave us a unique opportunity to form and test hypotheses about what the ancient Earth might have looked like and what these ancient organisms might have been.
Jeffrey Cameron, Associate Professor, Department of Biochemistry.
The researchers cultured vessels filled with bright green cyanobacteria in conditions similar to those on Earth 2 billion years ago to determine how similar these bacteria are.
As a result, the team announced that they appeared to have stumbled upon a living fossil hiding in plain sight. And, according to them, it is clear that the cyanobacteria that lived around the time of the Great Oxygenation Event did indeed have a structure similar to the carboxysome. This structure could help cells protect themselves from the increasing concentration of oxygen in the air.
Now scientists will conduct experiments to understand what life in the ocean was like 2 billion years ago.