Laser–Raman imagery of Earth's earliest fossils

@article{Schopf2002LaserRamanIO,
  title={Laser–Raman imagery of Earth's earliest fossils},
  author={J. William Schopf and Anatoliy B. Kudryavtsev and David G. Agresti and Thomas John Wdowiak and Andrew D. Czaja},
  journal={Nature},
  year={2002},
  volume={416},
  pages={73-76}
}
Unlike the familiar Phanerozoic history of life, evolution during the earlier and much longer Precambrian segment of geological time centred on prokaryotic microbes. Because such microorganisms are minute, are preserved incompletely in geological materials, and have simple morphologies that can be mimicked by nonbiological mineral microstructures, discriminating between true microbial fossils and microscopic pseudofossil ‘lookalikes’ can be difficult. Thus, valid identification of fossil… 
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