GSFC_180707_628
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RECORDS OF ANCIENT LIFE

On the early Earth, microbial mats were everywhere! Some produced stromatolites, which are stubby pillars that later became fossilized. Stromatolites are not fossils of organisms but instead are the fossilized remains of layered sedimentary grains captured by the bacterial colony. This image shows modern stromatolites located in Shark Bay, Western Australia.
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