Discussions asking whether “Snowball Earth” triggered animal evolution (see the bottom half of that page) suggest increasing evidence that the Snowball Earth hypothesis may explain an important part of why spacefaring civilizations seem rare.
photosynthetic organisms are limited by nutrients, most often nitrogen or phosphorous
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the glaciations led to high phosphorous concentrations, which led to high productivity, which led to high oxygen in the oceans and atmosphere, which allowed for animal evolution to be triggered and thus the rise of the metazoans.
This seems quite speculative, but if true it might mean that our planet needed a snowball earth effect for complex life to evolve, but also needed that snowball earth period to be followed by hundreds of millions of years without another snowball earth period that would wipe out complex life. It’s easy to imagine that the conditions needed to produce one snowball earth effect make it very unusual for the planet to escape repeated snowball earth events for as long as it did, thus explaining more of the Fermi paradox than seemed previously possible.