Electron microscopy of fossil bacteria two billion years old.
Occurrence of well-preserved rod-shaped and coccoid bacteria in the Precambrian Gunflint chert (1.9 x 10(9) years old) has been demonstrated by electron microscopy. This appears to be the oldest definite occurrence of bacteria in the fossil record. The organisms are morphologically comparable with certain modern iron bacteria.
D001419:Bacteria; D066298:In Vitro Techniques; D008854:Microscopy, Electron; D010163:Paleontology