Clusters of island horn in through hot ocean 3.4 billion years ago , when the world still had no atomic number 8 and the seas churned under a pallid , overcast sky . But life thrive on Earth even then , scientist say – and now they have the human beings ’s honest-to-god fossils to turn out it .
There were no plant or algae to photosynthesize and produce atomic number 8 , so microbic life used atomic number 16 for energy and ontogenesis , researchers say . Microfossils of these earliest microbe carry the sandstone record of life on Earth by about 300 million years .
“ This power to essentially ‘ breathe ’ S compounds has long been thought to be one of the earliest phase in the conversion from a non - biologic to biological public , ” said David Wacey , a postdoctoral research worker at the University of Western Australia who led the study .
atomic number 16 - based bacteria be today , in places likehydrothermal ventsandhot springs . And former Archaean rocks have demo grounds for ancient S - based metabolism as early as 3.5 billion years ago , but fossils of these sulfur - base life forms have been difficult to find and even more difficult to verify . Now researchers at UWA and the University of Oxford trust their newest breakthrough passes the test .
The dodo lie of carbonaceous cells and the protective sheath that housed them . They were found in the Strelley Pool Formation , an outcrop of sedimentary rocks in a remote field of honor in westerly Australia that represents the honest-to-goodness shoreline on the planet . The fogy were well - preserved between the quartz sand grains of the ancient beach , the research worker say .
The dodo resemble other , well - contemplate microfossil from 2 billion year ago , the research worker say . They were found clustered in grouping , stuck to sandpaper grains in appropriate habitats , and they were even find with pyrite ( fool ’s gold ) , which may be byproducts of their sulfur metabolism .
Researchers used Raman spectroscopy , mellow - resolve transmission negatron microscopy and geochemical depth psychology to show the fossils indeed comprise carbon - establish material and that it was not the solvent of some later contaminant . Writing in this hebdomad ’s edition of Nature Geoscience , they acknowledge it is notoriously unmanageable to examine the biologic nature of putative Archaean - era dodo – but they have several pieces of grounds in this fount , including the fogy ’ mineralogy and morphology .
apropos , the same Oxford team has studied other ancient fossils from a web site 20 miles away and consider them not good enough . Those fossils , from the Apex chert in Australia , did n’t have the good mineralogy and shape for them to be of biological origin , grant to an Oxford newsworthiness release about the Strelley Pool fossils . But these fogey do .
The researchers are now re - examining other dodo using the same method , attempt to determine if they also might contain grounds for life .
And , they say , they ’re thinking about the implications this study may have on exobiology . If life does survive – or did survive – elsewhere in the solar system , it might expect something like this . The researchers ’ thrifty evidence tests could be used to figure it out .
“ Could these sorts of things live on Mars ? It ’s just about conceivable , ” said Martin Brasier , a professor of palaeobiology at Oxford . “ But it would take these approaches – mapping the chemistry of any microfossil in fine particular and convince three - dimensional mental image – to support any evidence for living on Mars . ”
Image Credit : David Wacey / University of Western Australia
Popular Science is your wormhole to the future . Reporting on what ’s new and what ’s next in science and technology , we rescue the future tense now .
MarsScience
Daily Newsletter
Get the salutary tech , skill , and culture news in your inbox daily .
News from the future tense , fork over to your present tense .
You May Also Like
