Fuel for earliest life forms: Organic molecules found in 3.5 billion-year-old rocks

3.5 billion-year-old barite (bottom) with fossilized microbial mat (top). This barite is part of the Dresser Formation in NW Australia. Credit: Helge Missbach

A research team including the geobiologist Dr. Helge Missbach from the University of Cologne has detected organic molecules and gases trapped in 3.5-billion-year-old rocks. A widely accepted hypothesis says that the earliest life forms used small organic molecules as building materials and energy sources. However, the existence of such components in early habitats on Earth was as yet unproven. The current study, published in the journal Nature Communications, shows that solutions from archaic hydrothermal vents contained essential components that formed a basis for the earliest life on our planet.

Specifically, the scientists examined about 3.5-billion-year-old barites from the Dresser Formation in Western Australia. The barite thus dates from a time when early life developed on Earth. “In the field, the barites are directly associated with fossilized microbial mats, and they smell like rotten eggs when freshly scratched. Thus, we suspected that they contained organic material that might have served as nutrients for early microbial life,” said Dr. Helge Missbach of the Institute of Geology and Mineralogy and lead author of the study.

In the fluid inclusions, the team identified organic compounds such as acetic acid and methanethiol, in addition to gases such as carbon dioxide and hydrogen sulfide. These compounds may have been important substrates for metabolic processes of early microbial life. Furthermore, they are discussed as putative key agents in the origin of life on Earth. “The immediate connection between primordial molecules emerging from the subsurface and the microbial organisms—3.5 billion years ago—somehow surprised us. This finding contributes decisively to our understanding of the still unclear earliest evolutionary history of life on Earth,” Missbach concluded.


Landing on the origin of life


More information:
Nature Communications (2021). DOI: 10.1038/s41467-021-21323-z

Provided by
University of Cologne

Citation:
Fuel for earliest life forms: Organic molecules found in 3.5 billion-year-old rocks (2021, February 19)
retrieved 20 February 2021
from https://phys.org/news/2021-02-fuel-earliest-life-molecules-billion-year-old.html

This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no
part may be reproduced without the written permission. The content is provided for information purposes only.


Speak Your Mind

LEAVE A REPLY

Please enter your comment!
Please enter your name here

Get in Touch

350FansLike
100FollowersFollow
281FollowersFollow
150FollowersFollow

Recommend for You

Oh hi there 👋
It’s nice to meet you.

Subscribe and receive our weekly newsletter packed with awesome articles that really matters to you!

We don’t spam! Read our privacy policy for more info.

You might also like