Two articles on the emergence of life before animals. Continent Nuna of the Boring Billion 1800-800 Mya is surveyed. The life on land, from 1400-900 Mya, spanning Nuna's breakup, would be fungi.
Earth had surface oxygen by then; thanks to the algae and cyano, but their home was water. The plants could make no foothold on land. Until fungi allowed for symbiosis with lichen.
Lichen isn't preserved well; but we have a few additional tools from genomics of fungi and plants today. They're talking about horizonal gene transfer, like when retroviri burrow into animal genomes. These events can be used as before/after date-markers. And then, I guess, related to what events we can know about, like the timeline of a supercontinent connecting all the shoreland.
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