On October 19, 2015, Geochemists at the University of California Los Angeles (UCLA) found evidence of life's existence from at least 4.1 billion years ago, about 300 million years earlier than any previous research suggested. Furthermore, this discovery indicated the presence of life shortly after the planet's formation 4.54 billion years ago.
After examining the carbon isotopes of graphite preserved in a 4.1 billion-year-old zircon crystal in 2015, researchers at the University of California Los Angeles (UCLA) concluded they had found evidence of early life. The new evidence disputed early research that suggested life on earth began 3.8 billion years ago.
The discovery of early life beginning about 4.1 billion years ago was a significant milestone since earlier research suggested that life began 3.8 billion years ago. Shortly after the planet formed about 4.54 billion years ago, early life forms, including microbes, began to grow and evolve.
Researchers analyzed over 10,000 zircons (heavy, durable, diamond-like minerals that preserve materials, serving as time capsules). And apart from discovering evidence of early life, they also found the earth's oldest-known rock fragment that dates about 4.4 billion years.
During the research, the scientists narrowed the samples down from 10,000 to 79, hoping to find graphite. And out of these, only one tiny zircon fragment contained graphite inclusions. This fragment measured about half the width of a hair strand.