Published on November 14th, 20130
The oldest life forms on Earth were discovered!
In a study that could influence the search for life on other planets, an international team of scientists has found evidence of a complex microbial ecosystem dating back 3.5 billion years.
Evidence has been found in sedimentary rocks from the Pilbara region of Western Australia, a region that includes some of the oldest rocks.
Scientist David Wacey, involved in the research, from the University of Western Australia, said that this new evidence of ancient bacteria “are probably the oldest evidence of life on Earth”.
Specifically, scientists have discovered an ancient geological phenomenon called “induced sedimentary structures of microbes”. These structures were created by different communities of bacteria that respond to changes in sediment. These layers are commonly found in a variety of environments.
Previously, the oldest bacteria induced sedimentary structures that were discovered date back 3.2 billion years ago, but new discoveries are older than 300 million years, dating from Arheozoic.
Although, now, scientists could not observe micro cells, they found traces of bacterial communities on rocks.
3.5 billion years ago, Earth was a totally different place, with temperatures and sea levels much higher than now. Communities of bacteria such as the ones at Pilbara were the most advanced forms of life and the situation remained so for several billion years before complex life forms evolved.
“Bacteria ruled the world back then, it would’ve been a very smelly world indeed. In addition, the environment would be quite hostile. The sea had no oxygen, but there was more CO2 and methane, and the oceans were much warmer. Much of the world was covered with water and some dry surfaces here and there. It was dominated by sharp volcanic activity and more sulfur was found in the air”, said Professor David Wacey .
This research, scientists say, could have important implications in the future. “These communities of microbes could be seen from a rover on Mars … Also [ research ] might help us understand when life began and how the environment has evolved”, the study authors explained.