New fossil information confirms life on earth existed nearly 3.5 billion years ago.
The Beginnings of Life on Earth
While humanity has only been around for a short period of time, life on earth has been present for far longer. With the existence of our species measured at 3 million years, that seems like a long time in our narrow view of history. However, new evidence suggests that the beginnings of life on our planet originated around 3.5 billion years ago.
For quite some time, there has been a heated debate over the oldest fossils we’ve ever found. On December 18, however, Paleobiologists were able to conclusively confirm in the Proceedings of the National Academy of Sciences that bacteria and microbes existed billions of years ago — perhaps even living in a planet without any oxygen.
This cutting-edge research utilized the latest in technology to paint an accurate picture of early life on earth, and was carried out by a team led by William Schopf from the University of California-Los Angeles and John Valley of the University of Wisconsin-Madison. The dated fossils, originally found in 1982 in a rock formation in Western Australia, have been studied for over 30 years at this point — and new advancements in our ability to date fossils have finally given us a clearer view of the age of these ancient fossils.
Dating an Ancient Fossil
Back in 1993, Schopf gave an accurate estimation of the age of these bacteria and microbes, placing them at around 3.45 billion years old. However, scientists in the paleontology community argued that the conclusion was mere guesswork. In the current day, advancements in research have allowed the team led by Schopf and Valley to use a secondary ion spectrometer to obtain proof that backed up their previous findings.
The ion spectrometer worked by targeting carbon isotopes inside the fossil. Using the tool, scientists were able to separate that makeup of each fossil and compare it to regular rocks from the same period of time. The discrepancies in carbon-isotope ratios proved that Schopf was right all along about the age of these ancient fossils, and this gives us a reliable look at early life on earth that is difficult to dispute.
More notably, the research team was able to connect the isotope ratios to certain shapes in the fossil, which basically allows them to identify several different ancient beings. The discovery of five new organisms was a direct result of this research, which is yet another thrilling find on top of the exciting confirmation of the origins of life on earth. Two of the species identified were photosynthesizers, two consumed methane, and one organism produced methane.
In a statement from the University of Wisconsin-Madison, Valley stated his contentment and confidence in the find.
“I think it’s settled…These are a primitive but diverse group of organisms.”
With this new information about the oldest life on earth as well as the discovery of several new species, scientists are better equipped to understand the path our planet has taken from the first spark of life to modern human civilization.