Anaerobic life, first observance

The conventional wisdom is that the first observation of anaerobic microbial life was made by Louis Pasteur. In fact, Pasteur rediscovered the anaerobic lifestyle. The first person actually to see anaerobic microorganisms was Antony van Leeuwenhoek, who did a remarkable experiment in 1680,... 

Life evolved soon after Earth s formation, befiare any continents were present, during a time when the oceans were chemically and thermally controlled by tectonic processes. Thus, it has been proposed that the life evolved in hot anaerobic submarine environments similar to present-day hydrothermal vent systems. This hypothesis is supported by the observation of structures, thought to be the remains of protocells, in rocks formed by hydrothermal processes 3.5 to 3.8 billion years ago. Thus, the first organisms on Earth were probably anaerobic hyperthermophiles. Hydrothermal vent habitats probably offered an additional benefit by providing a stable environment relatively isolated from the catastrophic effects of bolide impacts. In other words, submarine hydrothermal vents coifld have acted as refugia enabling survival of early life forms. 

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