A way to bridge the gap:
Since the 1960s, many experts have argued that the emergence of eukaryotes (cells containing a clearly defined nucleus) happened in response to the oxygenation of Earth’s surface environment.
But a team led by the universities of Stanford and Exeter say recent advances in the Earth and life sciences challenge this view.
Their review says these breakthroughs “decouple” the emergence of eukaryotes (known as eukaryogenesis) from rising oxygen levels, and suggest eukaryotes in fact emerged in an anoxic (no-oxygen) environment in the ocean.
University of Exeter, “Origin of complex cells started without oxygen” at ScienceDaily (April 27, 2022)
Yes, the ham sandwich was invented that way too. It started without any ham…
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