Oldest hairy microbe fossils discovered - Technology & science - Science - LiveScience - msnbc.com: "The fossils have evaded researchers not only because they are so tiny, but also because these deposits do not contain a type of rock that typically preserves fossils, particularly something this small and fragile, she said.
Fossils belonging to foraminifera were found in rocks from Namibia, while ciliates were found in rocks from Mongolia. Both types first appear in layers of rock called cap carbonates, laid down as the world was leaving the earlier snowball state, which occurred 716 million years ago. [Photos: World's Most Famous Rocks ]"
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