Earliest organic evolution. Essay to the memory of Bartholomew Nagy

A review is presented of the currently available evidence of life in the Pr ecambrian, with special reference to microfossils of the size range 0.1-3 m um. The particles are spotted in thin sections of the rock under high apert ures of the light microscope, and have been examined in demineralized thick sections under the transmission electron microscope (TEM). They have been chemically analyzed utilizing microprobe and spectrophotometer microscopic techniques. On the basis of such studies, the interaction of microorganisms with the fo rmation of minerals can be traced back to early Archean times, 3800 million years ago. There is no indication supporting the assumption that some kind of prebiotic evolution took place in the recorded history of the Earth. Th e origin of life is open to alternative explanations, including extraterres trial phenomena. More information may be obtained from meteorites. Under high magnifications of the TEM, a portion of the carbonaceous matter in the Murchison, Orgueil and Allende meteorites appears to be structured. Particles of various morp hology can be distinguished. Microprobe techniques are applied to confirm t hat the microstructures are organic and indigenous to the rock. Possible or igins by self-assembly and morphogenesis are discussed. (C) 2001 Elsevier S cience B.V. All rights reserved.