Fossil Microbes Could be Earth’s Oldest Life
by Stephanie Pappas
Even before there was much oxygen on Earth, there was life, a new fossil discovery reveals. The findings have implications for finding alien life in our solar system such as on Mars, the researchers speculate.
Scientists have unearthed microscopic fossils of microbes that subsisted on sulfur instead of oxygen almost 3.5 billion years ago. At the time, the Earth was a warm, violent place without land plants or algae to produce oxygen through photosynthesis. The sky was overcast, trapping heat near Earth’s surface, and the oceans were the temperature of a hot bath.
“At last, we have good solid evidence for life over 3.4 billion years ago,” study researcher Martin Brasier of Oxford University said of the fossils, which were found in Australia. “It confirms there were bacteria at this time, living without oxygen.”
Sulfur-loving bacteria still exist today, found in hydrothermal vents, hot springs, soil and otherextreme environments that do not have much oxygen. The newly discovered fossils were found in some of the oldest sedimentary rocks on Earth, in a remote part of Western Australia called Strelley Pool…
(read more: Live Science) (image: David Wacey )